From 3c58f641e813c3c71039f8fd4d4e2a3aab713288 Mon Sep 17 00:00:00 2001 From: "Mike Rapoport (Microsoft)" Date: Thu, 18 Jun 2026 12:50:17 +0300 Subject: [PATCH 01/41] userfaultfd: prevent registration of special VMAs Vova Tokarev says: userfaultfd allows registration on shadow stack VMAs. With userfaultfd access, you can register on the shadow stack, discard a page ... and inject a page with chosen return addresses via UFFDIO_COPY. Update vma_can_userfault() to reject VM_SHADOW_STACK. While on it, also reject VM_SPECIAL so that if a driver would implement vm_uffd_ops, it wouldn't be possible to register special VMAs with userfaultfd. Since VM_SPECIAL includes VM_DONTEXPAND which is set but hugetlb, exclude hugetlb VMAs from the check for VM_SPECIAL. Link: https://lore.kernel.org/20260618095017.2553004-1-rppt@kernel.org Fixes: 54007f818206 ("mm: Introduce VM_SHADOW_STACK for shadow stack memory") Signed-off-by: Mike Rapoport (Microsoft) Reported-by: vova tokarev Acked-by: David Hildenbrand (Arm) Reviewed-by: Lorenzo Stoakes Cc: Al Viro Cc: Christian Brauner Cc: Jan Kara Cc: Linus Torvalds Cc: Mike Rapoport Cc: Oleg Nesterov Cc: Peter Xu Cc: Signed-off-by: Andrew Morton --- mm/userfaultfd.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 246af12bf80142..c3adedaaf7d547 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -2111,7 +2111,10 @@ static bool vma_can_userfault(struct vm_area_struct *vma, vm_flags_t vm_flags, { const struct vm_uffd_ops *ops = vma_uffd_ops(vma); - if (vma->vm_flags & VM_DROPPABLE) + if (vma->vm_flags & (VM_DROPPABLE | VM_SHADOW_STACK)) + return false; + + if (!is_vm_hugetlb_page(vma) && (vma->vm_flags & VM_SPECIAL)) return false; vm_flags &= __VM_UFFD_FLAGS; From 14afcf67dc2c3d2fce9f0b987a8fd4187777a841 Mon Sep 17 00:00:00 2001 From: SJ Park Date: Mon, 29 Jun 2026 18:38:18 -0700 Subject: [PATCH 02/41] MAINTAINERS: s/SeongJae/SJ/ My legal and preferred first names are SeongJae and SJ, respectively. I was using the legal name for commits and tags, while using the preferred name for conversations. It sometimes confuses people including myself. Consistently use the preferred name. Together remove copyright notes on files. Those are only confusing for people who are not familiar with the law. Meanwhile, we can infer the information in a better way from git logs and public information. Link: https://lore.kernel.org/20260630013820.143366-1-sj@kernel.org Signed-off-by: SJ Park Acked-by: Lorenzo Stoakes Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- .mailmap | 1 + .../ABI/testing/sysfs-kernel-mm-damon | 174 +++++++++--------- MAINTAINERS | 2 +- include/linux/damon.h | 2 - mm/damon/core.c | 2 - mm/damon/lru_sort.c | 2 - mm/damon/modules-common.c | 2 - mm/damon/modules-common.h | 2 - mm/damon/ops-common.c | 2 - mm/damon/ops-common.h | 2 - mm/damon/paddr.c | 2 - mm/damon/reclaim.c | 2 - mm/damon/sysfs-common.c | 2 - mm/damon/sysfs-common.h | 2 - mm/damon/sysfs-schemes.c | 2 - mm/damon/sysfs.c | 2 - mm/damon/tests/core-kunit.h | 4 - mm/damon/tests/sysfs-kunit.h | 2 - mm/damon/tests/vaddr-kunit.h | 4 - mm/damon/vaddr.c | 2 - 20 files changed, 89 insertions(+), 126 deletions(-) diff --git a/.mailmap b/.mailmap index 12f3acdebd7226..5f7654b9f80883 100644 --- a/.mailmap +++ b/.mailmap @@ -816,6 +816,7 @@ Simon Wunderlich Simon Wunderlich Simon Wunderlich Simon Wunderlich +SJ Park Sricharan Ramabadhran Srinivas Kandagatla Srinivas Kandagatla diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-damon b/Documentation/ABI/testing/sysfs-kernel-mm-damon index b73e6bc28ea5fc..4fdec63a47d4aa 100644 --- a/Documentation/ABI/testing/sysfs-kernel-mm-damon +++ b/Documentation/ABI/testing/sysfs-kernel-mm-damon @@ -1,26 +1,26 @@ what: /sys/kernel/mm/damon/ Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Interface for Data Access MONitoring (DAMON). Contains files for controlling DAMON. For more details on DAMON itself, please refer to Documentation/admin-guide/mm/damon/index.rst. What: /sys/kernel/mm/damon/admin/ Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Interface for privileged users of DAMON. Contains files for controlling DAMON that aimed to be used by privileged users. What: /sys/kernel/mm/damon/admin/kdamonds/nr_kdamonds Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for controlling each DAMON worker thread (kdamond) named '0' to 'N-1' under the kdamonds/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//state Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing 'on' or 'off' to this file makes the kdamond starts or stops, respectively. Reading the file returns the keywords based on the current status. Writing 'commit' to this file @@ -40,33 +40,33 @@ Description: Writing 'on' or 'off' to this file makes the kdamond starts or What: /sys/kernel/mm/damon/admin/kdamonds//pid Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the pid of the kdamond if it is running. What: /sys/kernel/mm/damon/admin/kdamonds//refresh_ms Date: Jul 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the time interval for automatic DAMON status file contents update. Writing '0' disables the update. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts/nr_contexts Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for controlling each DAMON context named '0' to 'N-1' under the contexts/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//avail_operations Date: Apr 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the available monitoring operations sets on the currently running kernel. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//operations Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a keyword for a monitoring operations set ('vaddr' for virtual address spaces monitoring, 'fvaddr' for fixed virtual address ranges monitoring, and 'paddr' for the physical address @@ -79,42 +79,42 @@ Description: Writing a keyword for a monitoring operations set ('vaddr' for What: /sys/kernel/mm/damon/admin/kdamonds//contexts//addr_unit Date: Aug 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing an integer to this file sets the 'address unit' parameter of the given operations set of the context. Reading the file returns the last-written 'address unit' value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//pause Date: Mar 2026 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a boolean keyword to this file sets the 'pause' request parameter for the context. Reading the file returns the last-written 'pause' value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/sample_us Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the sampling interval of the DAMON context in microseconds as the value. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/aggr_us Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the aggregation interval of the DAMON context in microseconds as the value. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/update_us Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the update interval of the DAMON context in microseconds as the value. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/intrvals_goal/access_bp Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the monitoring intervals auto-tuning target DAMON-observed access events ratio within the given time interval (aggrs in same directory), in bp @@ -122,7 +122,7 @@ Description: Writing a value to this file sets the monitoring intervals What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/intrvals_goal/aggrs Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the time interval to achieve the monitoring intervals auto-tuning target DAMON-observed access events ratio (access_bp in same directory) within. @@ -130,14 +130,14 @@ Description: Writing a value to this file sets the time interval to achieve What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/intrvals_goal/min_sample_us Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the minimum value of auto-tuned sampling interval in microseconds. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/intervals/intrvals_goal/max_sample_us Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the maximum value of auto-tuned sampling interval in microseconds. Reading this file returns the value. @@ -145,42 +145,42 @@ Description: Writing a value to this file sets the maximum value of What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/nr_regions/min WDate: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the minimum number of monitoring regions of the DAMON context as the value. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//monitoring_attrs/nr_regions/max Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the maximum number of monitoring regions of the DAMON context as the value. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//targets/nr_targets Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for controlling each DAMON target of the context named '0' to 'N-1' under the contexts/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//targets//pid_target Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the pid of the target process if the context is for virtual address spaces monitoring, respectively. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//targets//obsolete_target Date: Oct 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the obsoleteness of the matching parameters commit destination target. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//targets//regions/nr_regions Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for setting each DAMON target memory region of the context named '0' to 'N-1' under the regions/ directory. In @@ -190,181 +190,181 @@ Description: Writing a number 'N' to this file creates the number of What: /sys/kernel/mm/damon/admin/kdamonds//contexts//targets//regions//start Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the start address of the monitoring region. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//targets//regions//end Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the end address of the monitoring region. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes/nr_schemes Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for controlling each DAMON-based operation scheme of the context named '0' to 'N-1' under the schemes/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//action Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the action of the scheme. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//target_nid Date: Jun 2024 -Contact: SeongJae Park +Contact: SJ Park Description: Action's target NUMA node id. Supported by only relevant actions. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//apply_interval_us Date: Sep 2023 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a value to this file sets the action apply interval of the scheme in microseconds. Reading this file returns the value. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//access_pattern/sz/min Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the minimum size of the scheme's target regions in bytes. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//access_pattern/sz/max Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the maximum size of the scheme's target regions in bytes. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//access_pattern/nr_accesses/min Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the manimum 'nr_accesses' of the scheme's target regions. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//access_pattern/nr_accesses/max Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the maximum 'nr_accesses' of the scheme's target regions. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//access_pattern/age/min Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the minimum 'age' of the scheme's target regions. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//access_pattern/age/max Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the maximum 'age' of the scheme's target regions. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/ms Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the time quota of the scheme in milliseconds. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/bytes Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the size quota of the scheme in bytes. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/effective_bytes Date: Feb 2024 -Contact: SeongJae Park +Contact: SJ Park Description: Reading from this file gets the effective size quota of the scheme in bytes, which adjusted for the time quota and goals. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/reset_interval_ms Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the quotas charge reset interval of the scheme in milliseconds. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goals/nr_goals Date: Nov 2023 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for setting automatic tuning of the scheme's aggressiveness named '0' to 'N-1' under the goals/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goals//target_metric Date: Feb 2024 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the quota auto-tuning goal metric. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goals//target_value Date: Nov 2023 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the target value of the goal metric. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goals//current_value Date: Nov 2023 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the current value of the goal metric. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goals//nid Date: Apr 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the nid parameter of the goal. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goals//path Date: Oct 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the path parameter of the goal. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/goal_tuner Date: Mar 2026 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the goal-based effective quota auto-tuning algorithm to use. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/fail_charge_num Date: Mar 2026 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the action-failed memory quota charging ratio numerator. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/fail_charge_denom Date: Mar 2026 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the action-failed memory quota charging ratio denominator. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/weights/sz_permil Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the under-quota limit regions prioritization weight for 'size' in permil. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/weights/nr_accesses_permil Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the under-quota limit regions prioritization weight for 'nr_accesses' in permil. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//quotas/weights/age_permil Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the under-quota limit regions prioritization weight for 'age' in permil. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//watermarks/metric Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the metric of the watermarks for the scheme. The writable/readable keywords for this file are 'none' for disabling the watermarks @@ -373,44 +373,44 @@ Description: Writing to and reading from this file sets and gets the metric What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//watermarks/interval_us Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the metric check interval of the watermarks for the scheme in microseconds. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//watermarks/high Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the high watermark of the scheme in permil. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//watermarks/mid Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the mid watermark of the scheme in permil. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//watermarks/low Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the low watermark of the scheme in permil. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Directory for DAMON core layer-handled DAMOS filters. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters/nr_filters Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for setting filters of the scheme named '0' to 'N-1' under the core_filters/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//type Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the type of the memory of the interest. 'anon' for anonymous pages, 'memcg' for specific memory cgroup, 'young' for young pages, @@ -419,62 +419,62 @@ Description: Writing to and reading from this file sets and gets the type of What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//memcg_path Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: If 'memcg' is written to the 'type' file, writing to and reading from this file sets and gets the path to the memory cgroup of the interest. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//addr_start Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: If 'addr' is written to the 'type' file, writing to or reading from this file sets or gets the start address of the address range for the filter. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//addr_end Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: If 'addr' is written to the 'type' file, writing to or reading from this file sets or gets the end address of the address range for the filter. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//min Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: If 'hugepage_size' is written to the 'type' file, writing to or reading from this file sets or gets the minimum size of the hugepage for the filter. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//max Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: If 'hugepage_size' is written to the 'type' file, writing to or reading from this file sets or gets the maximum size of the hugepage for the filter. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//damon_target_idx Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: If 'target' is written to the 'type' file, writing to or reading from this file sets or gets the index of the DAMON monitoring target of the interest. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//matching Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing 'Y' or 'N' to this file sets whether the filter is for the memory of the 'type', or all except the 'type'. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters//allow Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing 'Y' or 'N' to this file sets whether to allow or reject applying the scheme's action to the memory that satisfies the 'type' and the 'matching' of the directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//ops_filters Date: Feb 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Directory for DAMON operations set layer-handled DAMOS filters. Files under this directory works same to those of /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//core_filters @@ -482,7 +482,7 @@ Description: Directory for DAMON operations set layer-handled DAMOS filters. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//filters Date: Dec 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Directory for DAMOS filters. Files under this directory works same to those of /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//{core,ops}_filters @@ -491,14 +491,14 @@ Description: Directory for DAMOS filters. Files under this directory works What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//dests/nr_dests Date: Jul 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number 'N' to this file creates the number of directories for setting action destinations of the scheme named '0' to 'N-1' under the dests/ directory. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//dests//id Date: Jul 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the id of the DAMOS action destination. For DAMOS_MIGRATE_{HOT,COLD} actions, the destination node's node id can be written and @@ -506,98 +506,98 @@ Description: Writing to and reading from this file sets and gets the id of What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//dests//weight Date: Jul 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing to and reading from this file sets and gets the weight of the DAMOS action destination to select as the destination of each action among the destinations. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/nr_tried Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the number of regions that the action of the scheme has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/sz_tried Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the total size of regions that the action of the scheme has tried to be applied in bytes. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/nr_applied Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the number of regions that the action of the scheme has successfully applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/sz_applied Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the total size of regions that the action of the scheme has successfully applied in bytes. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/sz_ops_filter_passed Date: Dec 2024 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the total size of memory that passed DAMON operations layer-handled filters of the scheme in bytes. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/qt_exceeds Date: Mar 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the number of the exceed events of the scheme's quotas. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/nr_snapshots Date: Dec 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the total number of DAMON snapshots that the scheme has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//stats/max_nr_snapshots Date: Dec 2025 -Contact: SeongJae Park +Contact: SJ Park Description: Writing a number to this file sets the upper limit of nr_snapshots that deactivates the scheme when the limit is reached or exceeded. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//tried_regions/total_bytes Date: Jul 2023 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the total amount of memory that corresponding DAMON-based Operation Scheme's action has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//tried_regions//start Date: Oct 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the start address of a memory region that corresponding DAMON-based Operation Scheme's action has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//tried_regions//end Date: Oct 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the end address of a memory region that corresponding DAMON-based Operation Scheme's action has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//tried_regions//nr_accesses Date: Oct 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the 'nr_accesses' of a memory region that corresponding DAMON-based Operation Scheme's action has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//tried_regions//age Date: Oct 2022 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the 'age' of a memory region that corresponding DAMON-based Operation Scheme's action has tried to be applied. What: /sys/kernel/mm/damon/admin/kdamonds//contexts//schemes//tried_regions//sz_filter_passed Date: Dec 2024 -Contact: SeongJae Park +Contact: SJ Park Description: Reading this file returns the size of the memory in the region that passed DAMON operations layer-handled filters of the scheme in bytes. diff --git a/MAINTAINERS b/MAINTAINERS index f37a81950e250e..a05d6741b24951 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7124,7 +7124,7 @@ W: https://docs.dasharo.com/ F: drivers/platform/x86/dasharo-acpi.c DAMON -M: SeongJae Park +M: SJ Park L: damon@lists.linux.dev L: linux-mm@kvack.org S: Maintained diff --git a/include/linux/damon.h b/include/linux/damon.h index 02ac34537df9a7..cfbbf8ba28f632 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -1,8 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * DAMON api - * - * Author: SeongJae Park */ #ifndef _DAMON_H_ diff --git a/mm/damon/core.c b/mm/damon/core.c index 7e4b9affc5b060..d99f7a297fdde6 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * Data Access Monitor - * - * Author: SeongJae Park */ #define pr_fmt(fmt) "damon: " fmt diff --git a/mm/damon/lru_sort.c b/mm/damon/lru_sort.c index 8298c6001fd097..32f41491b726b2 100644 --- a/mm/damon/lru_sort.c +++ b/mm/damon/lru_sort.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * DAMON-based LRU-lists Sorting - * - * Author: SeongJae Park */ #define pr_fmt(fmt) "damon-lru-sort: " fmt diff --git a/mm/damon/modules-common.c b/mm/damon/modules-common.c index 86d58f8c4f6358..f87fa46a95a088 100644 --- a/mm/damon/modules-common.c +++ b/mm/damon/modules-common.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * Common Code for DAMON Modules - * - * Author: SeongJae Park */ #include diff --git a/mm/damon/modules-common.h b/mm/damon/modules-common.h index f103ad55636872..6fd45490e45b63 100644 --- a/mm/damon/modules-common.h +++ b/mm/damon/modules-common.h @@ -1,8 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * Common Code for DAMON Modules - * - * Author: SeongJae Park */ #include diff --git a/mm/damon/ops-common.c b/mm/damon/ops-common.c index d1842e2b00ef83..6bdd1cfd3863a3 100644 --- a/mm/damon/ops-common.c +++ b/mm/damon/ops-common.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * Common Code for Data Access Monitoring - * - * Author: SeongJae Park */ #include diff --git a/mm/damon/ops-common.h b/mm/damon/ops-common.h index 5efa5b5970def7..38d295488fa181 100644 --- a/mm/damon/ops-common.h +++ b/mm/damon/ops-common.h @@ -1,8 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * Common Code for Data Access Monitoring - * - * Author: SeongJae Park */ #include diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c index d0598f5f268822..5c2da45f988cf9 100644 --- a/mm/damon/paddr.c +++ b/mm/damon/paddr.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * DAMON Code for The Physical Address Space - * - * Author: SeongJae Park */ #define pr_fmt(fmt) "damon-pa: " fmt diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c index ce4499cf4b8b05..11b70d0a9a6f0a 100644 --- a/mm/damon/reclaim.c +++ b/mm/damon/reclaim.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * DAMON-based page reclamation - * - * Author: SeongJae Park */ #define pr_fmt(fmt) "damon-reclaim: " fmt diff --git a/mm/damon/sysfs-common.c b/mm/damon/sysfs-common.c index bdc6ae2639e4f9..c59d7bf7a73ae0 100644 --- a/mm/damon/sysfs-common.c +++ b/mm/damon/sysfs-common.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * Common Code for DAMON Sysfs Interface - * - * Author: SeongJae Park */ #include diff --git a/mm/damon/sysfs-common.h b/mm/damon/sysfs-common.h index 3079306966a910..733764716e8dd9 100644 --- a/mm/damon/sysfs-common.h +++ b/mm/damon/sysfs-common.h @@ -1,8 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * Common Code for DAMON Sysfs Interface - * - * Author: SeongJae Park */ #include diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c index 0134111c3c1ff6..3cbeccd436e40f 100644 --- a/mm/damon/sysfs-schemes.c +++ b/mm/damon/sysfs-schemes.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * DAMON sysfs Interface - * - * Copyright (c) 2022 SeongJae Park */ #include diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 2e95e3bac774dc..a9e187158067d4 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * DAMON sysfs Interface - * - * Copyright (c) 2022 SeongJae Park */ #include diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h index 1cfb8c176b873e..fcf7c7fadb5fe5 100644 --- a/mm/damon/tests/core-kunit.h +++ b/mm/damon/tests/core-kunit.h @@ -1,10 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * Data Access Monitor Unit Tests - * - * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved. - * - * Author: SeongJae Park */ #ifdef CONFIG_DAMON_KUNIT_TEST diff --git a/mm/damon/tests/sysfs-kunit.h b/mm/damon/tests/sysfs-kunit.h index f9ec5e795b34b6..138a4b8d14e734 100644 --- a/mm/damon/tests/sysfs-kunit.h +++ b/mm/damon/tests/sysfs-kunit.h @@ -1,8 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * Data Access Monitor Unit Tests - * - * Author: SeongJae Park */ #ifdef CONFIG_DAMON_SYSFS_KUNIT_TEST diff --git a/mm/damon/tests/vaddr-kunit.h b/mm/damon/tests/vaddr-kunit.h index 563fbc7e3f4483..61f844336ffb50 100644 --- a/mm/damon/tests/vaddr-kunit.h +++ b/mm/damon/tests/vaddr-kunit.h @@ -1,10 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* * Data Access Monitor Unit Tests - * - * Copyright 2019 Amazon.com, Inc. or its affiliates. All rights reserved. - * - * Author: SeongJae Park */ #ifdef CONFIG_DAMON_VADDR_KUNIT_TEST diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c index d271476035641b..e73ec1ce016e5b 100644 --- a/mm/damon/vaddr.c +++ b/mm/damon/vaddr.c @@ -1,8 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* * DAMON Code for Virtual Address Spaces - * - * Author: SeongJae Park */ #define pr_fmt(fmt) "damon-va: " fmt From f84ca9b1888d8fce7dfefe0e750fa971f8797486 Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Tue, 30 Jun 2026 02:15:40 +0000 Subject: [PATCH 03/41] mm/page_vma_mapped: fix device-private PMD handling Commit 65edfda6f3f2 ("mm/rmap: extend rmap and migration support device-private entries") introduced the concept of device-private PMD entries, but did not correctly update the rmap walk code to account for them. As a result, when page_vma_mapped_walk() encounters device-private PMD entries, it takes no action other than to acquire the PMD lock and exit. However this is highly problematic for two reasons - firstly, device private entries possess a PFN so check_pmd() needs to be called to ensure an overlapping PFN range. Secondly, and more importantly, if PVMW_MIGRATION is set the caller assumes the returned entry is a migration entry, resulting in memory corruption when the caller tries to interpret the device private entry as such. In addition, commit 146287290023 ("mm/huge_memory: implement device-private THP splitting") allowed device private PMDs to be split like THP mappings, but again did not update this code path. As a result, we might race a PMD split prior to acquiring the PMD lock. This patch addresses all of these issues by invoking check_pmd(), ensuring PMVW_MIGRATION is not set and checks whether a split raced us we do for PMD THP and migration entries. Instead of checking for a subset of the cases after taking the pmd_lock(), put device-private along with pmd_trans_huge() and pmd_is_migration_entry(). Also remove thp_migration_supported() as it is already guarded by pmd_is_migration_entry(). [akpm@linux-foundation.org: fix Raspberry Pi 1 build, per David] Link: https://lore.kernel.org/20260630021540.17297-1-richard.weiyang@gmail.com Fixes: 65edfda6f3f2 ("mm/rmap: extend rmap and migration support device-private entries") Signed-off-by: Wei Yang Suggested-by: David Hildenbrand Reviewed-by: Lance Yang Acked-by: Balbir Singh Tested-by: Klara Modin Cc: SeongJae Park Cc: Zi Yan Cc: Lorenzo Stoakes Cc: q Signed-off-by: Andrew Morton --- mm/page_vma_mapped.c | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index 2ccbabfb2cc17a..bac2eb5de63d61 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -243,21 +243,31 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) */ pmde = pmdp_get_lockless(pvmw->pmd); - if (pmd_trans_huge(pmde) || pmd_is_migration_entry(pmde)) { + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && + (pmd_trans_huge(pmde) || pmd_is_migration_entry(pmde) || + pmd_is_device_private_entry(pmde))) { pvmw->ptl = pmd_lock(mm, pvmw->pmd); pmde = *pvmw->pmd; - if (!pmd_present(pmde)) { + if (pmd_is_migration_entry(pmde)) { softleaf_t entry; - if (!thp_migration_supported() || - !(pvmw->flags & PVMW_MIGRATION)) + if (!(pvmw->flags & PVMW_MIGRATION)) return not_found(pvmw); entry = softleaf_from_pmd(pmde); + if (!check_pmd(softleaf_to_pfn(entry), pvmw)) + return not_found(pvmw); + return true; + } else if (pmd_is_device_private_entry(pmde)) { + softleaf_t entry; - if (!softleaf_is_migration(entry) || - !check_pmd(softleaf_to_pfn(entry), pvmw)) + if (pvmw->flags & PVMW_MIGRATION) + return not_found(pvmw); + entry = softleaf_from_pmd(pmde); + if (!check_pmd(softleaf_to_pfn(entry), pvmw)) return not_found(pvmw); return true; + } else if (!pmd_present(pmde)) { + return not_found(pvmw); } if (likely(pmd_trans_huge(pmde))) { if (pvmw->flags & PVMW_MIGRATION) @@ -266,17 +276,10 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return not_found(pvmw); return true; } - /* THP pmd was split under us: handle on pte level */ + /* THP/device-private pmd was split under us: handle on pte level */ spin_unlock(pvmw->ptl); pvmw->ptl = NULL; } else if (!pmd_present(pmde)) { - const softleaf_t entry = softleaf_from_pmd(pmde); - - if (softleaf_is_device_private(entry)) { - pvmw->ptl = pmd_lock(mm, pvmw->pmd); - return true; - } - if ((pvmw->flags & PVMW_SYNC) && thp_vma_suitable_order(vma, pvmw->address, PMD_ORDER) && From e1cd30eceb6908fc13bebce41283b885d71ee8d6 Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Wed, 1 Jul 2026 13:42:34 -0400 Subject: [PATCH 04/41] mm/huge_memory: set PG_has_hwpoisoned only after new folio head is established __split_folio_to_order() copies the hwpoison state onto each new sub-folio while splitting a folio to a non-zero order. It does so via if (handle_hwpoison && page_range_has_hwpoisoned(new_head, new_nr_pages)) folio_set_has_hwpoisoned(new_folio); *before* clear_compound_head(new_head)/prep_compound_page(new_head, ...) turns @new_head from a tail page into a proper folio head. PG_has_hwpoisoned is a FOLIO_SECOND_PAGE flag, so folio_set_has_hwpoisoned() resolves to folio_flags(folio, 1). With the new compound_info-based page-flags layout, folio_flags() asserts the page is not a tail: VM_BUG_ON_PGFLAGS(page->compound_info & 1, page); VM_BUG_ON_PGFLAGS(n > 0 && !test_bit(PG_head, &page->flags.f), page); At the current call site @new_head still has the tail marker (compound_info bit 0 set, PG_head clear), so on CONFIG_DEBUG_VM kernels this hits: kernel BUG at include/linux/page-flags.h:354 folio_flags+0x82 folio_set_has_hwpoisoned __split_folio_to_order __split_unmapped_folio __folio_split truncate_inode_partial_folio (shmem hole-punch / MADV_REMOVE) Reproduced by syzkaller: hwpoison-inject a few subpages of a large shmem folio, then MADV_REMOVE (fallocate punch hole) on the same range, which splits the partial folio to a non-zero order. memory_failure() tries to split the poisoned folio to order 0 first, but that split is best-effort; when it fails the folio is left large with PG_has_hwpoisoned set, the case fa5a06170036 added this hwpoison copying for. Move the folio_set_has_hwpoisoned() call to after clear_compound_head()/prep_compound_page(), where @new_folio is a real order-new_order head folio (handle_hwpoison implies new_order != 0, so a second page always exists). The flag still lands on the same struct page (page[1] of the new folio); only the ordering relative to compound-head setup changes, satisfying the FOLIO_SECOND_PAGE precondition. Link: https://lore.kernel.org/20260701174235.3173401-1-riel@surriel.com Fixes: fa5a06170036 ("mm/huge_memory: preserve PG_has_hwpoisoned if a folio is split to >0 order") Signed-off-by: Rik van Riel Assisted-by: Claude:claude-opus-4-8 Reviewed-by: Zi Yan Acked-by: David Hildenbrand (Arm) Tested-by: Lance Yang Reviewed-by: Lorenzo Stoakes Reviewed-by: Baolin Wang Cc: Barry Song Cc: Dev Jain Cc: Lance Yang Cc: Liam R. Howlett Cc: Nico Pache Cc: Ryan Roberts Cc: Yang Shi Cc: Signed-off-by: Andrew Morton --- mm/huge_memory.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 2bccb0a53a0a60..b5d1e9d4463d00 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3587,10 +3587,6 @@ static void __split_folio_to_order(struct folio *folio, int old_order, (1L << PG_dropbehind) | LRU_GEN_MASK | LRU_REFS_MASK)); - if (handle_hwpoison && - page_range_has_hwpoisoned(new_head, new_nr_pages)) - folio_set_has_hwpoisoned(new_folio); - new_folio->mapping = folio->mapping; new_folio->index = folio->index + i; @@ -3612,6 +3608,14 @@ static void __split_folio_to_order(struct folio *folio, int old_order, folio_set_large_rmappable(new_folio); } + /* + * PG_has_hwpoisoned is on the 2nd page, so set it after + * the compound head is prepped. + */ + if (handle_hwpoison && + page_range_has_hwpoisoned(new_head, new_nr_pages)) + folio_set_has_hwpoisoned(new_folio); + if (folio_test_young(folio)) folio_set_young(new_folio); if (folio_test_idle(folio)) From 955b67c3ddf9912a670ed80eae7769745b4f405e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Mon, 25 May 2026 10:33:52 +0200 Subject: [PATCH 05/41] m68k: avoid -Wunused-but-set-parameter in clear_user_page() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The loop in clear_user_pages() iterates over all pages and calls clear_user_page() for each of them. During the loop "vaddr" is modified. However on m68k clear_user() is a macro which does not use "vaddr". The compiler sees a variable which is modified but never used and emits a warning for that: include/linux/highmem.h: In function 'clear_user_pages': include/linux/highmem.h:234:63: warning: parameter 'vaddr' set but not used [-Wunused-but-set-parameter=] static inline void clear_user_pages(void *addr, unsigned long vaddr, Other architectures use an inline function for clear_user_page() which avoids the warning. This is not possible on m68k, as dlush_dcache_page() is another macro which is not yet defined where clear_user_page() is defined. Including cacheflush_mm.h will trigger recursive and lots of other issues. So hide the warning with a cast to (void) instead. While we are here, do the same for copy_user_page(). Link: https://lore.kernel.org/20260525-m68k-clear_user_page-v2-1-0c8981c6eca1@weissschuh.net Fixes: 62a9f5a85b98 ("mm: introduce clear_pages() and clear_user_pages()") Signed-off-by: Thomas Weißschuh Acked-by: Geert Uytterhoeven Cc: Andreas Schwab Cc: Ankur Arora Cc: David Hildenbrand Cc: Signed-off-by: Andrew Morton --- arch/m68k/include/asm/page_mm.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/m68k/include/asm/page_mm.h b/arch/m68k/include/asm/page_mm.h index ed782609ca413f..0971a0651d490b 100644 --- a/arch/m68k/include/asm/page_mm.h +++ b/arch/m68k/include/asm/page_mm.h @@ -55,10 +55,12 @@ static inline void clear_page(void *page) #define clear_user_page(addr, vaddr, page) \ do { clear_page(addr); \ flush_dcache_page(page); \ + (void)(vaddr); \ } while (0) #define copy_user_page(to, from, vaddr, page) \ do { copy_page(to, from); \ flush_dcache_page(page); \ + (void)(vaddr); \ } while (0) extern unsigned long m68k_memoffset; From 1292c0ecb1caefb8ca064a3639d5673991e8810c Mon Sep 17 00:00:00 2001 From: SJ Park Date: Mon, 29 Jun 2026 20:52:19 -0700 Subject: [PATCH 06/41] mm/damon/core: validate ranges in damon_set_regions() DAMON core logic assumes zero length regions don't exist. However, a few DAMON API callers including DAMON_SYSFS, DAMON_RECLAIM and DAMON_LRU_SORT allow users to set empty monitoring target regions. This could result in WARN_ONCE() on CONFIG_DAMON_DEBUG_SANITY enabled kernel, and divide-by-zero from damon_merge_two_regions(). For example, the WANR_ONCE() can be triggered like below. # grep DAMON_DEBUG_SANITY /boot/config-$(uname -r) # CONFIG_DAMON_DEBUG_SANITY=y # damo start # cd /sys/kernel/mm/damon/admin/kdamonds/0 # echo 0 > contexts/0/targets/0/regions/0/start # echo 0 > contexts/0/targets/0/regions/0/end # echo commit > state # dmesg [....] [ 73.705780] ------------[ cut here ]------------ [ 73.707552] start 0 >= end 0 [ 73.708452] WARNING: mm/damon/core.c:359 at damon_new_region+0x6e/0x80, CPU#1: kdamond.0/758 [...] All DAMON API callers eventually use damon_set_regions() to setup the regions. Add the validation logic in the function. Link: https://lore.kernel.org/20260630035221.146458-1-sj@kernel.org Fixes: 43b0536cb471 ("mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)") Signed-off-by: SJ Park Cc: Yang yingliang Cc: # 5.16.x Signed-off-by: Andrew Morton --- mm/damon/core.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index d99f7a297fdde6..949d5309d54d3e 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -356,6 +356,12 @@ int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges, unsigned int i; int err; + for (i = 0; i < nr_ranges; i++) { + if (ALIGN_DOWN(ranges[i].start, min_region_sz) >= + ALIGN(ranges[i].end, min_region_sz)) + return -EINVAL; + } + /* Remove regions which are not in the new ranges */ damon_for_each_region_safe(r, next, t) { for (i = 0; i < nr_ranges; i++) { From e1a1729419e3e440668dbc1ae95b0dc2004172fe Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 15 May 2026 22:44:46 +0200 Subject: [PATCH 07/41] fat: avoid stack overflow warning Building the fat kunit tests on with -fsanitize=alignment reveals some rather excessive stack usage: fs/fat/fat_test.c: In function 'fat_clus_to_blknr_test': fs/fat/fat_test.c:33:1: error: the frame size of 4736 bytes is larger than 1536 bytes [-Werror=frame-larger-than=] 33 | } | ^ fs/fat/fat_test.c: In function 'fat_get_blknr_offset_test': fs/fat/fat_test.c:52:1: error: the frame size of 4800 bytes is larger than 1536 bytes [-Werror=frame-larger-than=] The problem is clearly related to the on-stack copy of a local msdos_sb_info structure. Avoid this by making that copy 'static const' and changing the called functions to accept a constant input. Link: https://lore.kernel.org/20260515204456.2692208-1-arnd@kernel.org Fixes: 410002f8139c ("kunit: fat: test cluster and directory i_pos layout helpers") Signed-off-by: Arnd Bergmann Acked-by: OGAWA Hirofumi Cc: Christian Brauner Cc: Jan Kara Cc: Adi Nata Cc: David Laight Signed-off-by: Andrew Morton --- fs/fat/fat.h | 4 ++-- fs/fat/fat_test.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/fat/fat.h b/fs/fat/fat.h index 99ed9228a677be..2772675bd35a36 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -249,13 +249,13 @@ static inline unsigned char fat_checksum(const __u8 *name) return s; } -static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) +static inline sector_t fat_clus_to_blknr(const struct msdos_sb_info *sbi, int clus) { return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus + sbi->data_start; } -static inline void fat_get_blknr_offset(struct msdos_sb_info *sbi, +static inline void fat_get_blknr_offset(const struct msdos_sb_info *sbi, loff_t i_pos, sector_t *blknr, int *offset) { *blknr = i_pos >> sbi->dir_per_block_bits; diff --git a/fs/fat/fat_test.c b/fs/fat/fat_test.c index 4eeed9dca54940..9583ce66dca3cd 100644 --- a/fs/fat/fat_test.c +++ b/fs/fat/fat_test.c @@ -22,7 +22,7 @@ static void fat_checksum_test(struct kunit *test) static void fat_clus_to_blknr_test(struct kunit *test) { - struct msdos_sb_info sbi = { + static const struct msdos_sb_info sbi = { .sec_per_clus = 4, .data_start = 100, }; @@ -34,7 +34,7 @@ static void fat_clus_to_blknr_test(struct kunit *test) static void fat_get_blknr_offset_test(struct kunit *test) { - struct msdos_sb_info sbi = { + static const struct msdos_sb_info sbi = { .dir_per_block = 16, .dir_per_block_bits = 4, }; From f8ed699d493aafb8a989cc7d10a027ea40bd422f Mon Sep 17 00:00:00 2001 From: Lance Yang Date: Thu, 2 Jul 2026 22:02:57 +0800 Subject: [PATCH 08/41] MAINTAINERS: add Usama as a THP reviewer Usama has been active around THP, really enjoys working on THPs, and tries to review all the patches that come in. Let's invite him to the THP party as a reviewer to help with the ongoing THP review load. Link: https://lore.kernel.org/20260702140257.44780-1-lance.yang@linux.dev Signed-off-by: Lance Yang Acked-by: David Hildenbrand (Arm) Acked-by: Lorenzo Stoakes Acked-by: Zi Yan Acked-by: Barry Song Acked-by: SJ Park Acked-by: Baolin Wang Cc: Dev Jain Cc: Liam R. Howlett Cc: Nico Pache Cc: Ryan Roberts Cc: Zi Yan Signed-off-by: Andrew Morton --- MAINTAINERS | 1 + 1 file changed, 1 insertion(+) diff --git a/MAINTAINERS b/MAINTAINERS index a05d6741b24951..852f7f0dd616fe 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -17255,6 +17255,7 @@ R: Ryan Roberts R: Dev Jain R: Barry Song R: Lance Yang +R: Usama Arif L: linux-mm@kvack.org S: Maintained W: http://www.linux-mm.org From 954157679ec34661c2e87e7eb796104a797c32db Mon Sep 17 00:00:00 2001 From: SJ Park Date: Fri, 3 Jul 2026 09:56:08 -0700 Subject: [PATCH 09/41] mm/damon/core: disallow overlapping input ranges for damon_set_regions() damon_set_regions() assumes the input ranges are sorted by the address and don't overlap each other. Hence the assumption was initially to be explicitly validated. But commit 97d482f4592f ("mm/damon/sysfs: reuse damon_set_regions() for regions setting") has mistakenly removed the validation. This can make DAMON behave in unexpected ways. At the best, the monitoring results snapshot will just look weird since there will be overlapping regions. DAMOS will also work weirdly, applying the same action multiple times for overlapping regions, and make DAMOS quota weird. More seriously, depending on the setup and regions updates sequence, negative size regions can be made. It will trigger WARN_ONCE() if the kernel is built with CONFIG_DAMON_DEBUG_SANITY=y. Depending on the monitoring results, the negative size region can further trigger division by zero in damon_merge_two_regions(). Note that some of the consequences including the WARN_ONCE() and the divide by zero depend on commits that were introduced after the root cause commit 97d482f4592f ("mm/damon/sysfs: reuse damon_set_regions() for regions setting"). Fix the problems by checking the assumption and returning an error if the input ranges don't meet the assumption. The issue was discovered [1] by Sashiko. Link: https://lore.kernel.org/20260703165610.92894-1-sj@kernel.org Link: https://lore.kernel.org/20260630041806.151124-1-sj@kernel.org [1] Fixes: 97d482f4592f ("mm/damon/sysfs: reuse damon_set_regions() for regions setting") Signed-off-by: SJ Park Cc: # 5.19.x Signed-off-by: Andrew Morton --- mm/damon/core.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/mm/damon/core.c b/mm/damon/core.c index 949d5309d54d3e..cff932b3317d08 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -354,12 +354,19 @@ int damon_set_regions(struct damon_target *t, struct damon_addr_range *ranges, { struct damon_region *r, *next; unsigned int i; + unsigned long last_end; int err; for (i = 0; i < nr_ranges; i++) { - if (ALIGN_DOWN(ranges[i].start, min_region_sz) >= - ALIGN(ranges[i].end, min_region_sz)) + unsigned long start, end; + + start = ALIGN_DOWN(ranges[i].start, min_region_sz); + end = ALIGN(ranges[i].end, min_region_sz); + if (start >= end) + return -EINVAL; + if (i > 0 && last_end > start) return -EINVAL; + last_end = end; } /* Remove regions which are not in the new ranges */ From 79c37ae3733e93d9d8ea12ecb44f717e61439024 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Fri, 3 Jul 2026 09:17:24 -0700 Subject: [PATCH 10/41] mm/kmemleak: fix checksum computation for per-cpu objects The per-cpu object checksum folds each CPU's CRC together with XOR and seeds every CRC with 0. Both choices make update_checksum() miss content changes: - XOR is self-cancelling, so equal contents on two CPUs cancel out and simultaneous identical changes leave the checksum unchanged. - crc32(0, ...) over all-zero content is 0, so a freshly allocated, zeroed per-cpu area checksums to 0, matching the initial value, and the object is never seen to change. See discussions at [0]. When update_checksum() wrongly reports an actively modified object as unchanged, kmemleak stops greying it for an extra scan and can report a live per-cpu object as a leak. Fold the per-cpu CRC as a single rolling checksum across all CPUs and initialise the object checksum to ~0 so the first computed value always registers as a change, even for content that hashes to 0. reset_checksum() is seeded the same way. Link: https://lore.kernel.org/all/akfYImSNDh3OjIfR@gmail.com [0] Link: https://lore.kernel.org/20260703-kmemleak_checksum-v1-1-5e0ab7d6966f@debian.org Fixes: 6c99d4eb7c5e ("kmemleak: enable tracking for percpu pointers") Signed-off-by: Breno Leitao Co-developed-by: Catalin Marinas Signed-off-by: Catalin Marinas Reviewed-by: Pavel Tikhomirov Cc: Signed-off-by: Andrew Morton --- mm/kmemleak.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 7c7ba17ce7af00..e196f53f9b4620 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -687,7 +687,7 @@ static struct kmemleak_object *__alloc_object(gfp_t gfp) atomic_set(&object->use_count, 1); object->excess_ref = 0; object->count = 0; /* white color initially */ - object->checksum = 0; + object->checksum = ~0; object->del_state = 0; /* task information */ @@ -981,7 +981,7 @@ static void reset_checksum(unsigned long ptr) } raw_spin_lock_irqsave(&object->lock, flags); - object->checksum = 0; + object->checksum = ~0; raw_spin_unlock_irqrestore(&object->lock, flags); put_object(object); } @@ -1410,7 +1410,8 @@ static bool update_checksum(struct kmemleak_object *object) for_each_possible_cpu(cpu) { void *ptr = per_cpu_ptr((void __percpu *)object->pointer, cpu); - object->checksum ^= crc32(0, kasan_reset_tag((void *)ptr), object->size); + object->checksum = crc32(object->checksum, + kasan_reset_tag((void *)ptr), object->size); } } else { object->checksum = crc32(0, kasan_reset_tag((void *)object->pointer), object->size); From 47c81dadb704cdf07bb8f9f43b4fbe758a351e08 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Sun, 5 Jul 2026 02:25:13 -0400 Subject: [PATCH 11/41] mm: page_reporting: allow driver to set batch capacity MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit At the moment, if a virtio balloon device has a page reporting vq but its size is < PAGE_REPORTING_CAPACITY (32), the balloon driver fails probe. But, there's no way for host to know this value, so it can easily create a smaller vq and suddenly adding the reporting capability to the device makes all of the driver fail. Not pretty. Add a capacity field to page_reporting_dev_info so drivers can control the maximum number of pages per report batch. In virtio-balloon, set the capacity to the reporting virtqueue size, letting page_reporting adapt to whatever the device provides. Capacity need not be a power of two. Code previously called out division by PAGE_REPORTING_CAPACITY as cheap since it was a power of 2, but no performance difference was observed with non-power-of-2 values. If capacity is 0 or exceeds PAGE_REPORTING_CAPACITY, it defaults to PAGE_REPORTING_CAPACITY. The 0 check and the clamping is done in page_reporting_register(), before the reporting work is scheduled, so we never get division by 0. Link: https://lore.kernel.org/444c24cf39f3f3620fc90ef4695bd6b0979f4c4b.1783232420.git.mst@redhat.com Fixes: b0c504f15471 ("virtio-balloon: add support for providing free page reports to host") Signed-off-by: Michael S. Tsirkin Assisted-by: Claude:claude-opus-4-6 Acked-by: David Hildenbrand (Arm) Reviewed-by: Gregory Price Acked-by: Zi Yan Reviewed-by: Pankaj Gupta Cc: Alexander Duyck Cc: Brendan Jackman Cc: Eugenio Pérez Cc: Jason Wang Cc: Johannes Weiner Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Xuan Zhuo Signed-off-by: Andrew Morton --- drivers/virtio/virtio_balloon.c | 5 +---- include/linux/page_reporting.h | 4 +++- mm/page_reporting.c | 24 ++++++++++++------------ 3 files changed, 16 insertions(+), 17 deletions(-) diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 088b3a0e6ce6cc..581ac799d97495 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -1017,10 +1017,6 @@ static int virtballoon_probe(struct virtio_device *vdev) unsigned int capacity; capacity = virtqueue_get_vring_size(vb->reporting_vq); - if (capacity < PAGE_REPORTING_CAPACITY) { - err = -ENOSPC; - goto out_unregister_oom; - } vb->pr_dev_info.order = PAGE_REPORTING_ORDER_UNSPECIFIED; @@ -1041,6 +1037,7 @@ static int virtballoon_probe(struct virtio_device *vdev) vb->pr_dev_info.order = 5; #endif + vb->pr_dev_info.capacity = capacity; err = page_reporting_register(&vb->pr_dev_info); if (err) goto out_unregister_oom; diff --git a/include/linux/page_reporting.h b/include/linux/page_reporting.h index 9d4ca5c218a0fb..272b1274efdc1c 100644 --- a/include/linux/page_reporting.h +++ b/include/linux/page_reporting.h @@ -5,7 +5,6 @@ #include #include -/* This value should always be a power of 2, see page_reporting_cycle() */ #define PAGE_REPORTING_CAPACITY 32 #define PAGE_REPORTING_ORDER_UNSPECIFIED -1 @@ -22,6 +21,9 @@ struct page_reporting_dev_info { /* Minimal order of page reporting */ unsigned int order; + + /* Max pages per report batch; 0 (default) means PAGE_REPORTING_CAPACITY */ + unsigned int capacity; }; /* Tear-down and bring-up for page reporting devices */ diff --git a/mm/page_reporting.c b/mm/page_reporting.c index 7418f2e500bb48..942e84b6908af7 100644 --- a/mm/page_reporting.c +++ b/mm/page_reporting.c @@ -173,11 +173,8 @@ page_reporting_cycle(struct page_reporting_dev_info *prdev, struct zone *zone, * any pages that may have already been present from the previous * list processed. This should result in us reporting all pages on * an idle system in about 30 seconds. - * - * The division here should be cheap since PAGE_REPORTING_CAPACITY - * should always be a power of 2. */ - budget = DIV_ROUND_UP(area->nr_free, PAGE_REPORTING_CAPACITY * 16); + budget = DIV_ROUND_UP(area->nr_free, prdev->capacity * 16); /* loop through free list adding unreported pages to sg list */ list_for_each_entry_safe(page, next, list, lru) { @@ -222,10 +219,10 @@ page_reporting_cycle(struct page_reporting_dev_info *prdev, struct zone *zone, spin_unlock_irq(&zone->lock); /* begin processing pages in local list */ - err = prdev->report(prdev, sgl, PAGE_REPORTING_CAPACITY); + err = prdev->report(prdev, sgl, prdev->capacity); /* reset offset since the full list was reported */ - *offset = PAGE_REPORTING_CAPACITY; + *offset = prdev->capacity; /* update budget to reflect call to report function */ budget--; @@ -234,7 +231,7 @@ page_reporting_cycle(struct page_reporting_dev_info *prdev, struct zone *zone, spin_lock_irq(&zone->lock); /* flush reported pages from the sg list */ - page_reporting_drain(prdev, sgl, PAGE_REPORTING_CAPACITY, !err); + page_reporting_drain(prdev, sgl, prdev->capacity, !err); /* * Reset next to first entry, the old next isn't valid @@ -260,13 +257,13 @@ static int page_reporting_process_zone(struct page_reporting_dev_info *prdev, struct scatterlist *sgl, struct zone *zone) { - unsigned int order, mt, leftover, offset = PAGE_REPORTING_CAPACITY; + unsigned int order, mt, leftover, offset = prdev->capacity; unsigned long watermark; int err = 0; /* Generate minimum watermark to be able to guarantee progress */ watermark = low_wmark_pages(zone) + - (PAGE_REPORTING_CAPACITY << page_reporting_order); + (prdev->capacity << page_reporting_order); /* * Cancel request if insufficient free memory or if we failed @@ -290,7 +287,7 @@ page_reporting_process_zone(struct page_reporting_dev_info *prdev, } /* report the leftover pages before going idle */ - leftover = PAGE_REPORTING_CAPACITY - offset; + leftover = prdev->capacity - offset; if (leftover) { sgl = &sgl[offset]; err = prdev->report(prdev, sgl, leftover); @@ -322,11 +319,11 @@ static void page_reporting_process(struct work_struct *work) atomic_set(&prdev->state, state); /* allocate scatterlist to store pages being reported on */ - sgl = kmalloc_objs(*sgl, PAGE_REPORTING_CAPACITY); + sgl = kmalloc_objs(*sgl, prdev->capacity); if (!sgl) goto err_out; - sg_init_table(sgl, PAGE_REPORTING_CAPACITY); + sg_init_table(sgl, prdev->capacity); for_each_zone(zone) { err = page_reporting_process_zone(prdev, sgl, zone); @@ -377,6 +374,9 @@ int page_reporting_register(struct page_reporting_dev_info *prdev) page_reporting_order = pageblock_order; } + if (!prdev->capacity || prdev->capacity > PAGE_REPORTING_CAPACITY) + prdev->capacity = PAGE_REPORTING_CAPACITY; + /* initialize state and work structures */ atomic_set(&prdev->state, PAGE_REPORTING_IDLE); INIT_DELAYED_WORK(&prdev->work, &page_reporting_process); From e57d6e9e20b551e4910d7a6331a81775c3ad6693 Mon Sep 17 00:00:00 2001 From: Xie Yuanbin Date: Fri, 5 Jun 2026 16:12:13 +0800 Subject: [PATCH 12/41] mm/memory-failure: trace: change memory_failure_event to ras subsystem Commit 97f0b1345219 ("tracing: add trace event for memory-failure") introduced memory_failure_event in ras subsystem. commit 31807483d395 ("mm/memory-failure: remove the selection of RAS") changed memory_failure_event to memory_failure subsystem. This breaks the backward compatibility, some user programs rely on it. Change memory_failure_event to ras subsystem to keep backward compatibility. Link: https://lore.kernel.org/20260605081213.154660-1-xieyuanbin1@huawei.com Fixes: 31807483d395 ("mm/memory-failure: remove the selection of RAS") Signed-off-by: Xie Yuanbin Reported-by: Yi Lai Reported-by: Qiuxu Zhuo Closes: https://lore.kernel.org/linux-mm/CY8PR11MB7134346A3E4BB28ECA28D6E989132@CY8PR11MB7134.namprd11.prod.outlook.com Acked-by: David Hildenbrand (Arm) Reviewed-by: Qiuxu Zhuo Reviewed-by: Lance Yang Reviewed-by: Miaohe Lin Tested-by: Qiuxu Zhuo Reviewed-by: Lance Yang Cc: Steven Rostedt Cc: Borislav Petkov Cc: Signed-off-by: Andrew Morton --- include/trace/events/memory-failure.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/include/trace/events/memory-failure.h b/include/trace/events/memory-failure.h index aa57cc8f896bed..7a8ee5d1a44e4d 100644 --- a/include/trace/events/memory-failure.h +++ b/include/trace/events/memory-failure.h @@ -1,6 +1,10 @@ /* SPDX-License-Identifier: GPL-2.0 */ #undef TRACE_SYSTEM -#define TRACE_SYSTEM memory_failure +/* + * For historical versions, memory_failure_event is in ras subsystem, + * some user programs depend on it. + */ +#define TRACE_SYSTEM ras #define TRACE_INCLUDE_FILE memory-failure #if !defined(_TRACE_MEMORY_FAILURE_H) || defined(TRACE_HEADER_MULTI_READ) From 1ecb29b084616ca423ca45ec6a6365da53411516 Mon Sep 17 00:00:00 2001 From: Ethan Nelson-Moore Date: Tue, 9 Jun 2026 20:32:47 -0700 Subject: [PATCH 13/41] x86/cpu: Remove Makefile rule for removed UMC CPU support Support for UMC CPUs was removed in 7d328c5de43a ("x86/cpu: Remove CPU_SUP_UMC_32 support"), but a Makefile rule for the support code remained. Remove it. Fixes: 7d328c5de43a ("x86/cpu: Remove CPU_SUP_UMC_32 support") Signed-off-by: Ethan Nelson-Moore Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Ahmed S. Darwish Link: https://patch.msgid.link/20260610033252.164571-1-enelsonmoore@gmail.com --- arch/x86/kernel/cpu/Makefile | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index d2e8a849f18057..5b1070ec85d946 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -46,7 +46,6 @@ obj-$(CONFIG_CPU_SUP_HYGON) += hygon.o obj-$(CONFIG_CPU_SUP_CYRIX_32) += cyrix.o obj-$(CONFIG_CPU_SUP_CENTAUR) += centaur.o obj-$(CONFIG_CPU_SUP_TRANSMETA_32) += transmeta.o -obj-$(CONFIG_CPU_SUP_UMC_32) += umc.o obj-$(CONFIG_CPU_SUP_ZHAOXIN) += zhaoxin.o obj-$(CONFIG_CPU_SUP_VORTEX_32) += vortex.o From d130041a7b96f79cd4c7079a6c2431a6db4c9619 Mon Sep 17 00:00:00 2001 From: Thorsten Blum Date: Sun, 21 Jun 2026 19:00:10 +0200 Subject: [PATCH 14/41] x86/boot: Reject too long acpi_rsdp= values cmdline_find_option() returns the full length of the parsed acpi_rsdp= value. get_cmdline_acpi_rsdp() then silently truncates values which do not fit in the val[] buffer. Prevent boot_kstrtoul() from parsing a truncated value and then the kernel from silently using the wrong RSDP address, see discussion in Link:. Issue a warning so that the user is aware that s/he supplied a malformed value and can get feedback instead of silent crashes. [ bp: Make commit message more precise. ] Fixes: 3c98e71b42a7 ("x86/boot: Add "acpi_rsdp=" early parsing") Signed-off-by: Thorsten Blum Signed-off-by: Borislav Petkov (AMD) Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20260617130417.36651-4-thorsten.blum@linux.dev --- arch/x86/boot/compressed/acpi.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c index f196b1d1ddf867..aed27604c11f0b 100644 --- a/arch/x86/boot/compressed/acpi.c +++ b/arch/x86/boot/compressed/acpi.c @@ -184,10 +184,15 @@ static unsigned long get_cmdline_acpi_rsdp(void) char val[MAX_ADDR_LEN] = { }; int ret; - ret = cmdline_find_option("acpi_rsdp", val, MAX_ADDR_LEN); + ret = cmdline_find_option("acpi_rsdp", val, sizeof(val)); if (ret < 0) return 0; + if (ret >= sizeof(val)) { + warn("acpi_rsdp= value too long; ignoring"); + return 0; + } + if (boot_kstrtoul(val, 16, &addr)) return 0; #endif From b6ea9680f8c101967caf9981c2980b80b818ccbf Mon Sep 17 00:00:00 2001 From: Vivian Wang Date: Mon, 13 Jul 2026 11:29:52 -0600 Subject: [PATCH 15/41] riscv: mm: Make mark_new_valid_map() stuff depend on 64BIT && MMU None of the code relating to mark_new_valid_map() does anything useful without CONFIG_64BIT=y && CONFIG_MMU=y, because the new_valid_map_cpus_check code is only used if CONFIG_64BIT, and the exception codes checked there can only happen with CONFIG_MMU=y. Therefore, make these conditional on CONFIG_64BIT=y && CONFIG_MMU=y to simplify programming, since we do not have to handle CONFIG_MMU=n when changing this code in the future. This also removes some unused code on the entry path for CONFIG_MMU=n. Signed-off-by: Vivian Wang Link: https://patch.msgid.link/20260713-mark-after-vmemmap-populate-v6-1-b945ceba29d4@iscas.ac.cn Signed-off-by: Paul Walmsley --- arch/riscv/include/asm/cacheflush.h | 2 +- arch/riscv/kernel/entry.S | 2 +- arch/riscv/mm/init.c | 2 ++ 3 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h index 8cfe59483a8f28..58e787fad029fd 100644 --- a/arch/riscv/include/asm/cacheflush.h +++ b/arch/riscv/include/asm/cacheflush.h @@ -40,7 +40,7 @@ do { \ flush_icache_mm(vma->vm_mm, 0); \ } while (0) -#ifdef CONFIG_64BIT +#if defined(CONFIG_64BIT) && defined(CONFIG_MMU) /* This is accessed in assembly code. cpumask_var_t would be too complex. */ extern DECLARE_BITMAP(new_valid_map_cpus, NR_CPUS); extern char _end[]; diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 08df724e13b9db..d799c4e56f8049 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -137,7 +137,7 @@ SYM_CODE_START(handle_exception) .Lrestore_kernel_tpsp: csrr tp, CSR_SCRATCH -#ifdef CONFIG_64BIT +#if defined(CONFIG_64BIT) && defined(CONFIG_MMU) /* * The RISC-V kernel does not flush TLBs on all CPUS after each new * vmalloc mapping or kfence_unprotect(), which may result in diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 5b1b3c88b4d130..3e450890be07e4 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -37,7 +37,9 @@ #include "../kernel/head.h" +#if defined(CONFIG_64BIT) && defined(CONFIG_MMU) DECLARE_BITMAP(new_valid_map_cpus, NR_CPUS); +#endif struct kernel_mapping kernel_map __ro_after_init; EXPORT_SYMBOL(kernel_map); From 4edd70ee6a7d0408a4e3ac921185779e7605f29c Mon Sep 17 00:00:00 2001 From: Vivian Wang Date: Mon, 13 Jul 2026 11:29:52 -0600 Subject: [PATCH 16/41] mm/sparse-vmemmap: flush_cache_vmap() after hotplugging vmemmap section_activate() does not flush TLB after populating new vmemmap pages. On most architectures, this is okay. However it is a problem on RISC-V since there the TLB caching non-present entries is permitted, which causes spurious faults on some hardwares. This seems to be most easily reproduced with DEBUG_VM=y and PAGE_POISONING=y, which causes these newly mapped struct pages to be poisoned i.e. written to immediately after mapping. Extend the RISC-V flush_cache_vmap() to also handle the vmemmap range, and call it after hotplugging vmemmap, which gets the possible spurious fault handled in the exception handler. At least for now, the only other architecture with both SPARSEMEM_VMEMMAP and flush_cache_vmap() is PowerPC, which has a similar problem with newly valid PTEs. But there flush_cache_vmap() is just a ptesync. So it should be safe to do this for generic code while having minimal performance impact. Suggested-by: Muchun Song Signed-off-by: Vivian Wang Reviewed-by: Muchun Song Acked-by: David Hildenbrand (Arm) Link: https://patch.msgid.link/20260713-mark-after-vmemmap-populate-v6-2-b945ceba29d4@iscas.ac.cn Signed-off-by: Paul Walmsley --- arch/riscv/include/asm/cacheflush.h | 3 ++- mm/sparse-vmemmap.c | 2 ++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h index 58e787fad029fd..c2b0a2928f0674 100644 --- a/arch/riscv/include/asm/cacheflush.h +++ b/arch/riscv/include/asm/cacheflush.h @@ -56,7 +56,8 @@ static inline void mark_new_valid_map(void) #define flush_cache_vmap flush_cache_vmap static inline void flush_cache_vmap(unsigned long start, unsigned long end) { - if (is_vmalloc_or_module_addr((void *)start)) + if (is_vmalloc_or_module_addr((void *)start) || + (start >= VMEMMAP_START && end <= VMEMMAP_END)) mark_new_valid_map(); } #define flush_cache_vmap_early(start, end) local_flush_tlb_kernel_range(start, end) diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c index 99e2be39671b63..ebd3ac997f645b 100644 --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -564,6 +564,8 @@ struct page * __meminit __populate_section_memmap(unsigned long pfn, if (r < 0) return NULL; + flush_cache_vmap(start, end); + return pfn_to_page(pfn); } From 3a2694bf6ac8e47b3814293e80343f58fc72937f Mon Sep 17 00:00:00 2001 From: Rui Qi Date: Mon, 6 Jul 2026 21:04:14 +0800 Subject: [PATCH 17/41] riscv: Gate FUNCTION_ALIGNMENT_4B on DYNAMIC_FTRACE The FUNCTION_ALIGNMENT_4B select forces the whole kernel to be built with -fmin-function-alignment=4. This alignment is only needed so the patchable-function-entry NOPs, which arch/riscv/Makefile emits under CONFIG_DYNAMIC_FTRACE, can be patched reliably on RISCV_ISA_C=y builds where compressed instructions otherwise allow 2-byte function alignment. The select is currently gated on HAVE_DYNAMIC_FTRACE, a capability bit that is selected whenever the toolchain supports dynamic ftrace, rather than on whether tracing is actually enabled. As a result every RISCV_ISA_C=y build gets 4-byte function alignment across the entire kernel even when function tracing is disabled, needlessly growing the kernel image and wasting instruction cache for a feature that is not in use. Gate the select on DYNAMIC_FTRACE instead, matching the condition under which arch/riscv/Makefile emits -fpatchable-function-entry, so the alignment is only applied when it is actually needed. Fixes: c41bf4326c7b ("riscv: ftrace: align patchable functions to 4 Byte boundary") Signed-off-by: Rui Qi Link: https://patch.msgid.link/20260706130415.463682-1-qirui.001@bytedance.com Signed-off-by: Paul Walmsley --- arch/riscv/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index c0a6992933e411..f7028caaeae06e 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -157,7 +157,7 @@ config RISCV select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS if MMU select HAVE_DYNAMIC_FTRACE if MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) - select FUNCTION_ALIGNMENT_4B if HAVE_DYNAMIC_FTRACE && RISCV_ISA_C + select FUNCTION_ALIGNMENT_4B if DYNAMIC_FTRACE && RISCV_ISA_C select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS if HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS if (DYNAMIC_FTRACE_WITH_ARGS && !CFI) select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE From 6dc3934152d1cc48b0395264d0061ebb4aed359e Mon Sep 17 00:00:00 2001 From: Yunhui Cui Date: Fri, 3 Jul 2026 20:28:30 +0800 Subject: [PATCH 18/41] riscv: io: avoid null-pointer arithmetic in PIO helpers When port I/O is not supported, exposing the port-string helpers is both unnecessary and can make clang diagnose null-pointer arithmetic from the PCI_IOBASE based address expression. Keep the MMIO string helpers available as before, but only provide the port I/O variants when CONFIG_HAS_IOPORT is enabled. Signed-off-by: Yunhui Cui Reviewed-by: Arnd Bergmann Link: https://patch.msgid.link/20260703122832.15984-2-cuiyunhui@bytedance.com Signed-off-by: Paul Walmsley --- arch/riscv/include/asm/io.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h index 09bb5f57a9d346..92d5f831f3495a 100644 --- a/arch/riscv/include/asm/io.h +++ b/arch/riscv/include/asm/io.h @@ -102,12 +102,14 @@ __io_reads_ins(reads, u32, l, __io_br(), __io_ar(addr)) #define readsw(addr, buffer, count) __readsw(addr, buffer, count) #define readsl(addr, buffer, count) __readsl(addr, buffer, count) +#ifdef CONFIG_HAS_IOPORT __io_reads_ins(ins, u8, b, __io_pbr(), __io_par(addr)) __io_reads_ins(ins, u16, w, __io_pbr(), __io_par(addr)) __io_reads_ins(ins, u32, l, __io_pbr(), __io_par(addr)) #define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count) #define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count) #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count) +#endif __io_writes_outs(writes, u8, b, __io_bw(), __io_aw()) __io_writes_outs(writes, u16, w, __io_bw(), __io_aw()) @@ -116,26 +118,32 @@ __io_writes_outs(writes, u32, l, __io_bw(), __io_aw()) #define writesw(addr, buffer, count) __writesw(addr, buffer, count) #define writesl(addr, buffer, count) __writesl(addr, buffer, count) +#ifdef CONFIG_HAS_IOPORT __io_writes_outs(outs, u8, b, __io_pbw(), __io_paw()) __io_writes_outs(outs, u16, w, __io_pbw(), __io_paw()) __io_writes_outs(outs, u32, l, __io_pbw(), __io_paw()) #define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count) #define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count) #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count) +#endif #ifdef CONFIG_64BIT __io_reads_ins(reads, u64, q, __io_br(), __io_ar(addr)) #define readsq(addr, buffer, count) __readsq(addr, buffer, count) +#ifdef CONFIG_HAS_IOPORT __io_reads_ins(ins, u64, q, __io_pbr(), __io_par(addr)) #define insq(addr, buffer, count) __insq(PCI_IOBASE + (addr), buffer, count) +#endif __io_writes_outs(writes, u64, q, __io_bw(), __io_aw()) #define writesq(addr, buffer, count) __writesq(addr, buffer, count) +#ifdef CONFIG_HAS_IOPORT __io_writes_outs(outs, u64, q, __io_pbr(), __io_paw()) #define outsq(addr, buffer, count) __outsq(PCI_IOBASE + (addr), buffer, count) #endif +#endif #include From ad6dcfa023762e37962f77ee48e752b7570e9440 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Wed, 1 Jul 2026 11:21:22 +0200 Subject: [PATCH 19/41] riscv: vdso: Do not use LTO for the vDSO MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With LTO enabled the compiler assumes that the vDSO functions are not used and optimizes them away completely. Currently this happens to __vdso_clock_getres(), __vdso_clock_gettime(), __vdso_getrandom(), __vdso_gettimeofday() and __vdso_riscv_hwprobe(). Disable LTO for the vDSO, as these functions are hand-optimized anyways. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202606301855.WvkSC4kD-lkp@intel.com/ Fixes: 021d23428bdb ("RISC-V: build: Allow LTO to be selected") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh Link: https://patch.msgid.link/20260701-riscv-vdso-lto-v1-1-89db0cd82077@linutronix.de Signed-off-by: Paul Walmsley --- arch/riscv/kernel/vdso/Makefile | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile index a842dc034571da..43ee881f6c6fd1 100644 --- a/arch/riscv/kernel/vdso/Makefile +++ b/arch/riscv/kernel/vdso/Makefile @@ -69,9 +69,9 @@ CPPFLAGS_$(vdso_lds) += -DHAS_VGETTIMEOFDAY endif # Disable -pg to prevent insert call site -CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) -CFLAGS_REMOVE_getrandom.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) -CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) +CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_LTO) +CFLAGS_REMOVE_getrandom.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_LTO) +CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_LTO) # Force dependency $(obj)/$(vdso_o): $(obj)/$(vdso_so) From ffa0aa5b625fe0bed7463ac613f8b06676ff4542 Mon Sep 17 00:00:00 2001 From: Thorsten Blum Date: Mon, 13 Jul 2026 21:49:25 +0200 Subject: [PATCH 20/41] x86/boot: Validate console=uart8250 baud rate to fix early boot hang When the baud rate is empty, 0, invalid, or overflows to 0 when stored as an int, the system will hang during early boot because of a division by zero in early_serial_init(). Fall back to DEFAULT_BAUD when the resulting baud rate is 0 to prevent an early system hang. Fixes: ce0aa5dd20e4 ("x86, setup: Make the setup code also accept console=uart8250") Signed-off-by: Thorsten Blum Signed-off-by: Ingo Molnar Cc: "H. Peter Anvin" Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260713194924.126472-3-thorsten.blum@linux.dev --- arch/x86/boot/early_serial_console.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86/boot/early_serial_console.c b/arch/x86/boot/early_serial_console.c index 023bf1c3de8b7a..5b83beab89e150 100644 --- a/arch/x86/boot/early_serial_console.c +++ b/arch/x86/boot/early_serial_console.c @@ -117,7 +117,7 @@ static unsigned int probe_baud(int port) static void parse_console_uart8250(void) { char optstr[64], *options; - int baud = DEFAULT_BAUD; + int baud; int port = 0; /* @@ -136,10 +136,13 @@ static void parse_console_uart8250(void) else return; - if (options && (options[0] == ',')) - baud = simple_strtoull(options + 1, &options, 0); - else + if (options && (options[0] == ',')) { + baud = simple_strtoull(options + 1, NULL, 0); + if (!baud) + baud = DEFAULT_BAUD; + } else { baud = probe_baud(port); + } if (port) early_serial_init(port, baud); From 0bcd59706aeda8a5d48ba656bab74cb26f2b423e Mon Sep 17 00:00:00 2001 From: Wang YuWei <1973615295@qq.com> Date: Mon, 6 Jul 2026 11:33:13 +0800 Subject: [PATCH 21/41] spi: dw-dma: Wait for controller idle before completing Tx dw_spi_dma_wait_tx_done() polls dw_spi_dma_tx_busy(), which only checks DW_SPI_SR_TF_EMPT. An empty TX FIFO merely means the last data word has been moved into the shift register; the transfer is not complete on the bus until DW_SPI_SR_BUSY is also cleared. As a result the wait can return while the controller is still shifting out the final word. Any caller that tears down or reconfigures the controller right after the transfer can then lose the tail of the transfer. The memory-operation path in spi-dw-core.c already waits for both DW_SPI_SR_BUSY == 0 and DW_SPI_SR_TF_EMPT == 1. Use the same completion condition in the DMA path so the transfer is guaranteed to be finished on the bus before the wait returns. Signed-off-by: Wang YuWei <1973615295@qq.com> Link: https://patch.msgid.link/tencent_4EA7B5C94669ED4C38A5F6C1C9126E5D9106@qq.com Signed-off-by: Mark Brown --- drivers/spi/spi-dw-dma.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-dw-dma.c b/drivers/spi/spi-dw-dma.c index bd70a7ed8067dc..f7d848fec9ab6d 100644 --- a/drivers/spi/spi-dw-dma.c +++ b/drivers/spi/spi-dw-dma.c @@ -282,7 +282,8 @@ static int dw_spi_dma_wait(struct dw_spi *dws, unsigned int len, u32 speed) static inline bool dw_spi_dma_tx_busy(struct dw_spi *dws) { - return !(dw_readl(dws, DW_SPI_SR) & DW_SPI_SR_TF_EMPT); + return (dw_readl(dws, DW_SPI_SR) & + (DW_SPI_SR_BUSY | DW_SPI_SR_TF_EMPT)) != DW_SPI_SR_TF_EMPT; } static int dw_spi_dma_wait_tx_done(struct dw_spi *dws, From e919ca35a6e84b5adf085da9ffa1544c01d4ce1e Mon Sep 17 00:00:00 2001 From: Srikanth Boyapally Date: Wed, 8 Jul 2026 10:21:48 +0530 Subject: [PATCH 22/41] spi: cadence-quadspi: Fix indirect write timeout when DMA read mode is enabled When use_dma_read is enabled, the IRQ handler unconditionally overwrites irq_status with the return value of get_dma_status(). For write operations, DMA status returns 0 since no DMA read is in progress, causing irq_status to become 0. The subsequent completion signal is never triggered and the write operation times out with -ETIMEDOUT: cadence-qspi f1010000.spi: Indirect write timeout spi-nor spi0.1: operation failed with -110 Fix this by separating the DMA completion path from the write interrupt path. If get_dma_status() indicates DMA read completion, signal completion and return immediately. Otherwise, preserve the original irq_status so that write completion interrupts are correctly recognized and signalled. Fixes: aac733a96636 ("spi: cadence-qspi: Fix style and improve readability") Signed-off-by: Srikanth Boyapally Reviewed-by: Radhey Shyam Pandey Link: https://patch.msgid.link/20260708045148.2993313-1-srikanth.boyapally@amd.com Signed-off-by: Mark Brown --- drivers/spi/spi-cadence-quadspi.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c index aaba1a3ad57783..ecb0be39469651 100644 --- a/drivers/spi/spi-cadence-quadspi.c +++ b/drivers/spi/spi-cadence-quadspi.c @@ -382,12 +382,16 @@ static irqreturn_t cqspi_irq_handler(int this_irq, void *dev) /* Clear interrupt */ writel(irq_status, cqspi->iobase + CQSPI_REG_IRQSTATUS); - if (cqspi->use_dma_read && ddata && ddata->get_dma_status) - irq_status = ddata->get_dma_status(cqspi); - else if (cqspi->slow_sram) + if (cqspi->use_dma_read && ddata && ddata->get_dma_status) { + if (ddata->get_dma_status(cqspi)) { + complete(&cqspi->transfer_complete); + return IRQ_HANDLED; + } + } else if (cqspi->slow_sram) { irq_status &= CQSPI_IRQ_MASK_RD_SLOW_SRAM | CQSPI_IRQ_MASK_WR; - else + } else { irq_status &= CQSPI_IRQ_MASK_RD | CQSPI_IRQ_MASK_WR; + } if (irq_status) complete(&cqspi->transfer_complete); From f1596ba3e6b390aa0fef8466afce44efecf39d8d Mon Sep 17 00:00:00 2001 From: Jaeyeong Lee Date: Sun, 12 Jul 2026 14:27:12 +0000 Subject: [PATCH 23/41] io_uring/kbuf: free the replaced iovec after a successful grow The provided-buffer validation fix deferred freeing a cached iovec until validation completed. However, the deferred free uses arg->iovs. After a grow, that points to the newly allocated array. Without a grow, it points to the cached array that remains in use. This leaves the caller with a dangling iovec in both cases and can result in repeated frees. Only free org_iovs when arg->iovs actually replaced it. Fixes: cd053d788c3f ("io_uring: fix dangling iovec after provided-buffer bundle grow failure") Assisted-by: Codex:gpt-5.3-codex-spark Signed-off-by: Jaeyeong Lee Link: https://patch.msgid.link/20260712142612.188695595-iostreampy@proton.me Signed-off-by: Jens Axboe --- io_uring/kbuf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c index b6b969b55e1224..de0129bceaba30 100644 --- a/io_uring/kbuf.c +++ b/io_uring/kbuf.c @@ -328,8 +328,8 @@ static int io_ring_buffers_peek(struct io_kiocb *req, struct buf_sel_arg *arg, buf = io_ring_head_to_buf(br, ++head, bl->mask); } while (--nr_iovs); - if (arg->mode & KBUF_MODE_FREE) - kfree(arg->iovs); + if (arg->iovs != org_iovs && (arg->mode & KBUF_MODE_FREE)) + kfree(org_iovs); if (head == tail) req->flags |= REQ_F_BL_EMPTY; From cc609376e9a43166a2fba2aef6c5f9ea262ce722 Mon Sep 17 00:00:00 2001 From: Yi Xie Date: Tue, 14 Jul 2026 11:03:06 +0800 Subject: [PATCH 24/41] io_uring/fs: check unused sqe fields for unlinkat Zero check unused SQE fields addr3 and pad2 for unlinkat. They're not needed now, but could be used sometime in the future. Signed-off-by: Yi Xie Reviewed-by: Gabriel Krisman Bertazi Link: https://patch.msgid.link/20260714030306.64820-1-xieyi@kylinos.cn Signed-off-by: Jens Axboe --- io_uring/fs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/io_uring/fs.c b/io_uring/fs.c index d0580c754bf867..26ea841a22e700 100644 --- a/io_uring/fs.c +++ b/io_uring/fs.c @@ -110,7 +110,8 @@ int io_unlinkat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) const char __user *fname; int err; - if (sqe->off || sqe->len || sqe->buf_index || sqe->splice_fd_in) + if (sqe->off || sqe->len || sqe->buf_index || sqe->splice_fd_in || + sqe->addr3 || sqe->__pad2[0]) return -EINVAL; if (unlikely(req->flags & REQ_F_FIXED_FILE)) return -EBADF; From e4bf6eb4c7b61db1cf24487e14e6ae8755e61e3d Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Tue, 23 Jun 2026 22:40:57 +0200 Subject: [PATCH 25/41] arch/riscv: vdso: remove CFI landing pad from rt_sigreturn When CONFIG_RISCV_USER_CFI is enabled, the CFI version of the vDSO, has a CFI landing pad instruction at the start of __vdso_rt_sigreturn. This breaks libgcc's unwinding code which matches on the first two instructions. Other unwinders that rely on similar instruction matching may also be affected. Since __vdso_rt_sigreturn is reached as part of signal-return handling rather than via an indirect call/jump from userspace, it does not need a CFI landing pad. Remove it and restore the instruction sequence expected by existing unwinding code. This matches what was done on arm64 in commit 9a964285572b ("arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction") for a similar issue. Cc: stable@vger.kernel.org Fixes: 37f57bd3faea ("arch/riscv: compile vdso with landing pad and shadow stack note") Co-authored-by: Joel Stanley Signed-off-by: Aurelien Jarno Signed-off-by: Joel Stanley Link: https://patch.msgid.link/20260623204058.498120-1-aurelien@aurel32.net [pjw@kernel.org: fixed comment style] Signed-off-by: Paul Walmsley --- arch/riscv/kernel/vdso/rt_sigreturn.S | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/vdso/rt_sigreturn.S b/arch/riscv/kernel/vdso/rt_sigreturn.S index e82987dc37394b..d6f96b1abe409b 100644 --- a/arch/riscv/kernel/vdso/rt_sigreturn.S +++ b/arch/riscv/kernel/vdso/rt_sigreturn.S @@ -7,11 +7,19 @@ #include #include +/* + * WARNING: Do NOT add a CFI landing pad at the start of this function. + * Unwinders such as libgcc identify the sigreturn trampoline by matching the + * instruction sequence. Adding a landing pad here would break unwinding from + * signal handlers. + * + * This trampoline is used only for signal return and not via an indirect + * call/jump from userspace, so adding CFI landing pad is unnecessary. + */ .text SYM_FUNC_START(__vdso_rt_sigreturn) .cfi_startproc .cfi_signal_frame - vdso_lpad li a7, __NR_rt_sigreturn ecall .cfi_endproc From 5caae1deee89a6582c761d5dcd4b924b744426cc Mon Sep 17 00:00:00 2001 From: Mark Harris Date: Mon, 13 Jul 2026 17:30:56 -0700 Subject: [PATCH 26/41] riscv: hwprobe: Avoid uninitialized read in hwprobe_get_cpus() When cpusetsize < cpumask_size(), hwprobe_get_cpus() did not fully initialize its copy of the cpu mask, which could cause non-deterministic results from the riscv_hwprobe syscall on a system with more than 8 CPUs when the supplied cpu mask is empty. Address this by fully initializing the cpu mask. Fixes: e178bf146e4b ("RISC-V: hwprobe: Introduce which-cpus flag") Signed-off-by: Mark Harris Reviewed-by: Nam Cao Reviewed-by: Michael Ellerman Link: https://patch.msgid.link/20260714003056.73707-1-mark.hsj@gmail.com Signed-off-by: Paul Walmsley --- arch/riscv/kernel/sys_hwprobe.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c index 1659d31fd288fc..caf6762427c87e 100644 --- a/arch/riscv/kernel/sys_hwprobe.c +++ b/arch/riscv/kernel/sys_hwprobe.c @@ -450,6 +450,7 @@ static int hwprobe_get_cpus(struct riscv_hwprobe __user *pairs, if (cpusetsize > cpumask_size()) cpusetsize = cpumask_size(); + cpumask_clear(&cpus); ret = copy_from_user(&cpus, cpus_user, cpusetsize); if (ret) return -EFAULT; From 691b052139c94ee6640ac39e0b764dd3867897c0 Mon Sep 17 00:00:00 2001 From: Mike Waychison Date: Wed, 15 Jul 2026 15:29:50 -0400 Subject: [PATCH 27/41] block: fix race in blk_time_get_ns() returning 0 blk_time_get_ns() populates the per-plug cached timestamp and then returns it by re-reading the field: if (!plug->cur_ktime) { plug->cur_ktime = ktime_get_ns(); current->flags |= PF_BLOCK_TS; } return plug->cur_ktime; This is problematic when the compiler emits the final "return plug->cur_ktime" as a reload from memory, after PF_BLOCK_TS has already been set. Since the cached timestamp is now invalidated from finish_task_switch() (fad156c2af22 "block: invalidate cached plug timestamp after task switch"), a task preempted between setting PF_BLOCK_TS and that reload has plug->cur_ktime zeroed by blk_plug_invalidate_ts() when it is scheduled back in. The reload then returns 0. A 0 handed back here is stored as a start timestamp -- e.g. blk_account_io_start() writes it to rq->start_time_ns -- and later subtracted from "now". blk_account_io_done() then adds (now - 0), i.e. roughly the system uptime, to the per-group nsecs[] counters. On an otherwise idle, healthy device this appears as sudden ~uptime-sized jumps in the diskstats time fields (write_ticks/discard_ticks/time_in_queue). The solution is to be explicit in our reads and writes to this field that is preemption volatile. We also add a barrier() to ensure that any setting of PF_BLOCK_TS is ordered to happen after the cur_ktime update. This issue was discovered using AI-assisted kprobes looking for paths that were leaking zeroed timestamps in a live system, based on the observation that we were sometimes seeing uptime-sized jumps in kernel exported counters. This was flagged by NodeDiskIOSaturation prometheus alerts that started firing on all hosts post 7.1.3 kernel upgrade, due to node-exporter now exporting a nonsensical node_disk_io_time_weighted_seconds_total. Fixes: fad156c2af22 ("block: invalidate cached plug timestamp after task switch") Cc: stable@vger.kernel.org Signed-off-by: Mike Waychison Assisted-by: Claude:claude-opus-4.8 Link: https://patch.msgid.link/20260715192950.2488921-1-mike@waychison.com Signed-off-by: Jens Axboe --- block/blk.h | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/block/blk.h b/block/blk.h index fb95d3c58950c1..eaac05815cb036 100644 --- a/block/blk.h +++ b/block/blk.h @@ -717,6 +717,7 @@ static inline int req_ref_read(struct request *req) static inline u64 blk_time_get_ns(void) { struct blk_plug *plug = current->plug; + u64 now; if (!plug || !in_task()) return ktime_get_ns(); @@ -725,12 +726,18 @@ static inline u64 blk_time_get_ns(void) * 0 could very well be a valid time, but rather than flag "this is * a valid timestamp" separately, just accept that we'll do an extra * ktime_get_ns() if we just happen to get 0 as the current time. + * + * cur_ktime can be zeroed by pre-emption the moment PF_BLOCK_TS is set. */ - if (!plug->cur_ktime) { - plug->cur_ktime = ktime_get_ns(); + now = READ_ONCE(plug->cur_ktime); + if (!now) { + now = ktime_get_ns(); + WRITE_ONCE(plug->cur_ktime, now); + /* Ensure PF_BLOCK_TS is set after cur_ktime. */ + barrier(); current->flags |= PF_BLOCK_TS; } - return plug->cur_ktime; + return now; } static inline ktime_t blk_time_get(void) From c4f4c0fc551cbcdccbbbc2d874d7d6440c7b4983 Mon Sep 17 00:00:00 2001 From: Daan De Meyer Date: Wed, 15 Jul 2026 21:39:57 +0200 Subject: [PATCH 28/41] loop: remove manually added partitions on detach Commit 267ec4d7223a ("loop: fix partition scan race between udev and loop_reread_partitions()") stopped disk_force_media_change() from setting GD_NEED_PART_SCAN because loop devices with LO_FLAGS_PARTSCAN rescan partitions explicitly. However, partitions can also be added manually with BLKPG while LO_FLAGS_PARTSCAN is clear. When such a loop device is detached, __loop_clr_fd() skips bdev_disk_changed(). Without GD_NEED_PART_SCAN, reopening the unbound device no longer performs the previous lazy cleanup, leaving dead partition devices behind. A subsequent LOOP_CONFIGURE can then fail its partition scan with -EBUSY, as seen in blktests loop/009 after loop/008. Call bdev_disk_changed() unconditionally during __loop_clr_fd(). The disk capacity is already zero and the release path holds open_mutex, so this drops all partitions without rescanning the detached backing file. The new blktests loop/013 case covers this sequence by adding a partition with BLKPG without LO_FLAGS_PARTSCAN, detaching the loop device, and checking that the partition is gone when the device is reopened. Fixes: 267ec4d7223a ("loop: fix partition scan race between udev and loop_reread_partitions()") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202607150754.b660f5b9-lkp@intel.com Signed-off-by: Daan De Meyer Link: https://patch.msgid.link/20260715-b4-loop-partition-cleanup-v1-1-b9f59910cd1e@amutable.com Signed-off-by: Jens Axboe --- drivers/block/loop.c | 32 ++++++++++++++------------------ 1 file changed, 14 insertions(+), 18 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 310de0463beb14..1faecef330092b 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -1113,6 +1113,7 @@ static void __loop_clr_fd(struct loop_device *lo) struct queue_limits lim; struct file *filp; gfp_t gfp = lo->old_gfp_mask; + int err; spin_lock_irq(&lo->lo_lock); filp = lo->lo_backing_file; @@ -1146,26 +1147,21 @@ static void __loop_clr_fd(struct loop_device *lo) disk_force_media_change(lo->lo_disk); - if (lo->lo_flags & LO_FLAGS_PARTSCAN) { - int err; - - /* - * open_mutex has been held already in release path, so don't - * acquire it if this function is called in such case. - * - * If the reread partition isn't from release path, lo_refcnt - * must be at least one and it can only become zero when the - * current holder is released. - */ - err = bdev_disk_changed(lo->lo_disk, false); - if (err) - pr_warn("%s: partition scan of loop%d failed (rc=%d)\n", - __func__, lo->lo_number, err); - /* Device is gone, no point in returning error */ - } + /* + * Remove all partitions, including partitions added manually with + * BLKPG, which may exist even if LO_FLAGS_PARTSCAN is not set. + * + * open_mutex has been held already in release path, so don't acquire + * it here. + */ + err = bdev_disk_changed(lo->lo_disk, false); + if (err) + pr_warn("%s: partition scan of loop%d failed (rc=%d)\n", + __func__, lo->lo_number, err); + /* Device is gone, no point in returning error */ /* - * lo->lo_state is set to Lo_unbound here after above partscan has + * lo->lo_state is set to Lo_unbound here after removing partitions has * finished. There cannot be anybody else entering __loop_clr_fd() as * Lo_rundown state protects us from all the other places trying to * change the 'lo' device. From dbbca20764382b4d411ec2918f4e278ffe547acc Mon Sep 17 00:00:00 2001 From: Tao Cui Date: Wed, 15 Jul 2026 21:24:07 +0800 Subject: [PATCH 29/41] blk-cgroup: fix leaks and online flag on radix_tree_insert failure MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When radix_tree_insert() fails in blkg_create(), the error path has two issues: 1. blkg->online is set to true unconditionally, even when the blkg was never fully inserted. Move the assignment inside the success block. 2. The error path calls blkg_put() without first calling percpu_ref_kill(). Because the refcount is still in percpu mode, percpu_ref_put() only does this_cpu_sub() without checking for zero, so blkg_release() is never triggered. This permanently leaks the blkg memory, its percpu iostat, policy data, the parent blkg reference, and the cgroup css reference — the latter preventing the cgroup from ever being destroyed. Fix by replacing blkg_put() with percpu_ref_kill(), matching the pattern used in blkg_destroy(). Acked-by: Tejun Heo Signed-off-by: Tao Cui Link: https://patch.msgid.link/20260715132407.1469777-1-cui.tao@linux.dev Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index d2a1f5903f248a..d9676126c5b5da 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -434,15 +434,15 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, struct gendisk *disk, blkg->pd[i]->online = true; } } + blkg->online = true; } - blkg->online = true; spin_unlock(&blkcg->lock); if (!ret) return blkg; /* @blkg failed fully initialized, use the usual release path */ - blkg_put(blkg); + percpu_ref_kill(&blkg->refcnt); return ERR_PTR(ret); err_free_blkg: From d35e236282992e583ed9c1b7ab52e9ef1b873585 Mon Sep 17 00:00:00 2001 From: Michael Bommarito Date: Tue, 14 Jul 2026 07:48:06 -0400 Subject: [PATCH 30/41] partitions: aix: bound the lvd scan to one sector aix_partition() reads the logical-volume descriptor array as a single sector and then scans it: if (numlvs && (d = read_part_sector(state, vgda_sector + 1, §))) { struct lvd *p = (struct lvd *)d; ... for (i = 0; foundlvs < numlvs && i < state->limit; i++) { lvip[i].pps_per_lv = be16_to_cpu(p[i].num_lps); p points at a single 512-byte sector, which holds SECTOR_SIZE / sizeof(struct lvd) = 16 entries, but the loop runs until foundlvs reaches the on-disk numlvs or i reaches state->limit (DISK_MAX_PARTS, 256). numlvs is an on-disk __be16 read straight from the volume group descriptor and is not validated, so a crafted AIX image with numlvs larger than 16 and lvd entries whose num_lps fields are zero (so foundlvs never advances) drives the loop to read p[i] well past the end of the read sector buffer. Commit d97a86c170b4 ("partitions: aix.c: off by one bug") hardened the matching write of lvip[lv_ix] in 2014 but left this read loop unbounded. Bound the scan to the number of struct lvd entries that fit in the sector that was actually read. Fixes: 6ceea22bbbc8 ("partitions: add aix lvm partition support files") Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Michael Bommarito Link: https://patch.msgid.link/20260714114806.3761553-1-michael.bommarito@gmail.com Signed-off-by: Jens Axboe --- block/partitions/aix.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/block/partitions/aix.c b/block/partitions/aix.c index f3c4174e003e9d..689837deba279b 100644 --- a/block/partitions/aix.c +++ b/block/partitions/aix.c @@ -208,7 +208,14 @@ int aix_partition(struct parsed_partitions *state) if (n) { int foundlvs = 0; - for (i = 0; foundlvs < numlvs && i < state->limit; i += 1) { + /* + * The lvd array was read as a single sector; only the + * struct lvd entries that fit in it are valid. Bound the + * scan so an on-disk numlvs larger than that cannot walk + * the read buffer out of bounds. + */ + for (i = 0; foundlvs < numlvs && i < state->limit && + i < SECTOR_SIZE / (int)sizeof(struct lvd); i++) { lvip[i].pps_per_lv = be16_to_cpu(p[i].num_lps); if (lvip[i].pps_per_lv) foundlvs += 1; From daff723f2d4c618d5f9186a990f47bf75878abeb Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 14 Jul 2026 18:37:39 +0930 Subject: [PATCH 31/41] block: do not warn when doing greedy allocation in folio_alloc_greedy() During one of my local btrfs fstests runs, folio_alloc() inside folio_alloc_greedy() triggered an allocation failure report when trying to allocate an order-4 folio. The kernel is from the latest development branch, which is utilizing the IOMAP_DIO_BOUNCE flag for direct writes when the inode requires checksum. Unfortunately I didn't save the full log, only the function and the order. When the IOMAP_DIO_BOUNCE flag is utilized, we will hit the following call chain: bio_iov_iter_bounce_write() |- folio_alloc_greedy() |- folio_alloc(gfp | __GFP_NORETRY, get_order(*size)); However __GFP_NORETRY will still emit an allocation failure report when it fails. And folio_alloc_greedy() will retry with a smaller order anyway, there is no point in emitting that allocation failure report. Append the __GFP_NOWARN flag to folio_alloc() for the larger-order folio attempts. Fixes: 8dd5e7c75d7b ("block: add helpers to bounce buffer an iov_iter into bios") Signed-off-by: Qu Wenruo Link: https://patch.msgid.link/d10571445ee505d95ba6eaad7558fc1f556d2921.1784020005.git.wqu@suse.com Signed-off-by: Jens Axboe --- block/bio.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/block/bio.c b/block/bio.c index f2a5f4d0a9672b..5ac954c70dd015 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1285,7 +1285,8 @@ static struct folio *folio_alloc_greedy(gfp_t gfp, size_t *size, struct folio *folio; while (*size > minsize) { - folio = folio_alloc(gfp | __GFP_NORETRY, get_order(*size)); + folio = folio_alloc(gfp | __GFP_NORETRY | __GFP_NOWARN, + get_order(*size)); if (folio) return folio; *size = rounddown_pow_of_two(*size - 1); From bd2df8dc72201f626d66ca97f2afc8b7f2740713 Mon Sep 17 00:00:00 2001 From: Jackie Liu Date: Wed, 15 Jul 2026 15:35:18 +0800 Subject: [PATCH 32/41] block: free copied pages when blk_rq_map_kern() fails bio_copy_kern() allocates pages that are normally freed by the bio completion callback. If blk_rq_append_bio() rejects the bio, however, blk_rq_map_kern() only drops the bio reference. Since bio_put() does not free pages referenced by the bio vectors, those pages leak. This can happen when the bio exceeds the queue segment constraints or when a later mapping cannot be merged into a request built by earlier calls. Track whether the buffer was copied and free those pages before dropping the rejected bio. Fixes: 3a5a39276d2a ("block: allow blk_rq_map_kern to append to requests") Assisted-by: Codex:gpt-5.6-sol Signed-off-by: Jackie Liu Reviewed-by: Christoph Hellwig Link: https://patch.msgid.link/20260715073518.96042-1-liu.yun@linux.dev Signed-off-by: Jens Axboe --- block/blk-map.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/block/blk-map.c b/block/blk-map.c index 768549f19f97ec..d1d6bbe0ecf1f9 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -653,6 +653,7 @@ int blk_rq_map_kern(struct request *rq, void *kbuf, unsigned int len, gfp_t gfp_mask) { unsigned long addr = (unsigned long) kbuf; + bool do_copy; struct bio *bio; int ret; @@ -661,7 +662,8 @@ int blk_rq_map_kern(struct request *rq, void *kbuf, unsigned int len, if (!len || !kbuf) return -EINVAL; - if (!blk_rq_aligned(rq->q, addr, len) || object_is_on_stack(kbuf)) + do_copy = !blk_rq_aligned(rq->q, addr, len) || object_is_on_stack(kbuf); + if (do_copy) bio = bio_copy_kern(rq, kbuf, len, gfp_mask); else bio = bio_map_kern(rq, kbuf, len, gfp_mask); @@ -670,8 +672,11 @@ int blk_rq_map_kern(struct request *rq, void *kbuf, unsigned int len, return PTR_ERR(bio); ret = blk_rq_append_bio(rq, bio); - if (unlikely(ret)) + if (unlikely(ret)) { + if (do_copy) + bio_free_pages(bio); blk_mq_map_bio_put(bio); + } return ret; } EXPORT_SYMBOL(blk_rq_map_kern); From 4ff58d6bc9dd4c7fe6092d0ab5677a79ebc788af Mon Sep 17 00:00:00 2001 From: Shin'ichiro Kawasaki Date: Thu, 16 Jul 2026 18:22:37 +0900 Subject: [PATCH 33/41] block: serialize elevator changes for the same queue using a writer lock When elevator_change() is called concurrently for the same queue, the elevator_change_done() function runs concurrently as well. This function adds or deletes kobjects for the debugfs entry of the queue. Then the concurrent calls cause memory corruption of the kobjects and result in a process hang. The core part of the elevator switch is protected by queue freeze and q->elevator_lock. However, since the commit 559dc11143eb ("block: move elv_register[unregister]_queue out of elevator_lock"), the elevator_change_done() is not serialized. Hence the memory corruption and the hang. The failures are observed when udev-worker writes to a sysfs queue/scheduler attribute file while the blktests test case block/005 writes to the same attribute file. The failure also can be recreated by running two processes that write to the same queue/scheduler file concurrently. The failure is observed since another commit 370ac285f23a ("block: avoid cpu_hotplug_lock depedency on freeze_lock"). This commit changed the behavior of queue freeze and it unveiled the failure. Fix the failure by changing elv_iosched_store() to acquire update_nr_hwq_lock as the writer lock instead of the reader lock. This serializes the whole elevator switch steps, including the elevator_change_done() call. Fixes: 559dc11143eb ("block: move elv_register[unregister]_queue out of elevator_lock") Signed-off-by: Shin'ichiro Kawasaki Reviewed-by: Nilay Shroff Reviewed-by: Ming Lei Link: https://patch.msgid.link/20260716092237.1305030-1-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe --- block/elevator.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/block/elevator.c b/block/elevator.c index 3bcd37c2aa3401..2161b6eea680ca 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -812,8 +812,13 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf, * reference during concurrent disk deletion: * update_nr_hwq_lock -> kn->active (via del_gendisk -> kobject_del) * kn->active -> update_nr_hwq_lock (via this sysfs write path) + * + * Use the writer lock instead of the reader lock of update_nr_hwq_lock + * to serialize the two-stage elevator switch steps in + * elevator_change(): the core switch step under the elevator lock and + * the elevator_change_done() step outside the elevator lock. */ - if (!down_read_trylock(&set->update_nr_hwq_lock)) { + if (!down_write_trylock(&set->update_nr_hwq_lock)) { ret = -EBUSY; goto out; } @@ -824,7 +829,7 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf, } else { ret = -ENOENT; } - up_read(&set->update_nr_hwq_lock); + up_write(&set->update_nr_hwq_lock); out: if (ctx.type) From f94de432646ebec7857ba2624fe082e779b52572 Mon Sep 17 00:00:00 2001 From: Jackie Liu Date: Wed, 15 Jul 2026 15:33:41 +0800 Subject: [PATCH 34/41] block: show operation in error injection rules Rules listed through the error_injection debugfs file omit the block operation they match. As a result, rules that differ only in operation are indistinguishable even though op is mandatory when adding a rule. Signed-off-by: Jackie Liu Reviewed-by: Christoph Hellwig Link: https://patch.msgid.link/20260715073341.95129-1-liu.yun@linux.dev Signed-off-by: Jens Axboe --- block/error-injection.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/block/error-injection.c b/block/error-injection.c index cfb83138960c86..e14bc4b723efb0 100644 --- a/block/error-injection.c +++ b/block/error-injection.c @@ -276,9 +276,10 @@ static int blk_error_injection_show(struct seq_file *s, void *private) rcu_read_lock(); list_for_each_entry_rcu(inj, &disk->error_injection_list, entry) { - seq_printf(s, "%llu:%llu status=%s,chance=%u", - inj->start, inj->end, - blk_status_to_tag(inj->status), inj->chance); + seq_printf(s, "%llu:%llu op=%s,status=%s,chance=%u", + inj->start, inj->end, + blk_op_str(inj->op), + blk_status_to_tag(inj->status), inj->chance); seq_putc(s, '\n'); } rcu_read_unlock(); From 447cfed6d700bfbd5a7120f8ea5821a0e1191667 Mon Sep 17 00:00:00 2001 From: Joseph Qi Date: Thu, 9 Jul 2026 10:01:45 +0800 Subject: [PATCH 35/41] block: try slab allocation in bio_alloc_bioset() before mempool When the per-CPU bio cache is enabled but empty, bio_alloc_percpu_cache() returns NULL and bio_alloc_bioset() falls straight through to the mempool fallback: if (unlikely(!bio)) { if (!(saved_gfp & __GFP_DIRECT_RECLAIM)) return NULL; ... } For non-sleeping allocations (no __GFP_DIRECT_RECLAIM) this returns NULL without ever attempting a slab allocation, even when there is plenty of free memory. Commit b520c4eef83d ("block: split bio_alloc_bioset more clearly into a fast and slowpath") introduced this. Before it, a percpu cache miss fell through to mempool_alloc(), which attempted the underlying slab allocation first and only failed when that slab allocation failed. The restructuring dropped the slab attempt that non-sleeping callers of a cache-enabled bioset (such as the default fs_bio_set used by bio_alloc()) relied on. Try a slab allocation with optimistic GFP_ flags before falling back to the mempool whenever the bio is still NULL, so both the cache-empty and non-cache paths share the same slab attempt. This restores the previous behavior for non-sleeping allocations. Fixes: b520c4eef83d ("block: split bio_alloc_bioset more clearly into a fast and slowpath") Suggested-by: Christoph Hellwig Signed-off-by: Joseph Qi Reviewed-by: Christoph Hellwig Link: https://patch.msgid.link/20260709020145.4011533-1-joseph.qi@linux.alibaba.com Signed-off-by: Jens Axboe --- block/bio.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/block/bio.c b/block/bio.c index 5ac954c70dd015..de56d3f10c56da 100644 --- a/block/bio.c +++ b/block/bio.c @@ -555,6 +555,14 @@ struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs, bio = bio_alloc_percpu_cache(bs); } else { opf &= ~REQ_ALLOC_CACHE; + } + + /* + * For a bioset without a percpu cache, or when the percpu cache was + * empty, try a slab allocation with optimistic GFP_ flags before + * falling back to the mempool. + */ + if (!bio) { p = kmem_cache_alloc(bs->bio_slab, gfp); if (p) bio = p + bs->front_pad; From 4f221efff9b32fb4206f8db240a2b35a7d27696d Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 16 Jul 2026 11:12:45 +0200 Subject: [PATCH 36/41] block: handle huge zero folios in bio_free_folios When CONFIG_PERSISTENT_HUGE_ZERO_FOLIO is enabled, iomap_dio_zero() can add a huge zero folio to a zeroing bio, which needs special treatment in bio_free_folios by also checking is_huge_zero_folio() in addition to is_zero_folio(). Fixes: 8dd5e7c75d7b ("block: add helpers to bounce buffer an iov_iter into bios") Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Link: https://patch.msgid.link/20260716091306.316625-2-hch@lst.de Signed-off-by: Jens Axboe --- block/bio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/bio.c b/block/bio.c index de56d3f10c56da..ebb6d3e53ac39e 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1311,7 +1311,7 @@ static void bio_free_folios(struct bio *bio) bio_for_each_bvec_all(bv, bio, i) { struct folio *folio = bvec_folio(bv); - if (!is_zero_folio(folio)) + if (!is_zero_folio(folio) && !is_huge_zero_folio(folio)) folio_put(folio); } } From df308a14585649f7683a560f5c94978ab4f8224d Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 16 Jul 2026 11:12:46 +0200 Subject: [PATCH 37/41] block: fix aligning of bounced dio read bios bio_iov_iter_align_down expects the "normal" biovec layout from vector 0, while bio_iov_iter_bounce_read abuses vector 0 for a bounce buffer allocation. Pass an explicit bvec to bio_iov_iter_align_down to deal with this case to avoid a double unpin. Additionally we need to free the folio if no bio_vec could be added, and adjust the size of the first bio_vec that contains the bounce buffer when the I/O size is aligned down. Fixes: e7b8b3c5b2a6 ("block: align down bounces bios") Reported-by: 0wnerD1ed Signed-off-by: Christoph Hellwig Tested-by: 0wnerD1ed Reviewed-by: Keith Busch Link: https://patch.msgid.link/20260716091306.316625-3-hch@lst.de Signed-off-by: Jens Axboe --- block/bio.c | 51 ++++++++++++++++++++++++++++----------------------- 1 file changed, 28 insertions(+), 23 deletions(-) diff --git a/block/bio.c b/block/bio.c index ebb6d3e53ac39e..6a2f6fc3413e89 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1199,7 +1199,7 @@ void bio_iov_bvec_set(struct bio *bio, const struct iov_iter *iter) * for the next iteration. */ static int bio_iov_iter_align_down(struct bio *bio, struct iov_iter *iter, - unsigned len_align_mask) + struct bio_vec *bv, unsigned len_align_mask) { size_t nbytes = bio->bi_iter.bi_size & len_align_mask; @@ -1208,23 +1208,16 @@ static int bio_iov_iter_align_down(struct bio *bio, struct iov_iter *iter, iov_iter_revert(iter, nbytes); bio->bi_iter.bi_size -= nbytes; - do { - struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; - - if (nbytes < bv->bv_len) { - bv->bv_len -= nbytes; - break; - } - + while (nbytes >= bv->bv_len) { if (bio_flagged(bio, BIO_PAGE_PINNED)) unpin_user_page(bv->bv_page); - bio->bi_vcnt--; + if (!--bio->bi_vcnt) + return -EFAULT; nbytes -= bv->bv_len; - } while (nbytes); - - if (!bio->bi_vcnt) - return -EFAULT; + bv--; + } + bv->bv_len -= nbytes; return 0; } @@ -1284,7 +1277,8 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter, if (is_pci_p2pdma_page(bio->bi_io_vec->bv_page)) bio->bi_opf |= REQ_NOMERGE; - return bio_iov_iter_align_down(bio, iter, len_align_mask); + return bio_iov_iter_align_down(bio, iter, + &bio->bi_io_vec[bio->bi_vcnt - 1], len_align_mask); } static struct folio *folio_alloc_greedy(gfp_t gfp, size_t *size, @@ -1369,7 +1363,8 @@ static int bio_iov_iter_bounce_write(struct bio *bio, struct iov_iter *iter, if (!bio->bi_iter.bi_size) return -ENOMEM; - return bio_iov_iter_align_down(bio, iter, minsize - 1); + return bio_iov_iter_align_down(bio, iter, + &bio->bi_io_vec[bio->bi_vcnt - 1], minsize - 1); } static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter, @@ -1377,21 +1372,18 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter, { size_t len = min3(iov_iter_count(iter), maxlen, SZ_1M); struct folio *folio; + ssize_t ret; folio = folio_alloc_greedy(GFP_KERNEL, &len, minsize); if (!folio) return -ENOMEM; do { - ssize_t ret; - ret = iov_iter_extract_bvecs(iter, bio->bi_io_vec + 1, len, &bio->bi_vcnt, bio->bi_max_vecs - 1, 0); if (ret <= 0) { - if (!bio->bi_vcnt) { - folio_put(folio); - return ret; - } + if (!bio->bi_vcnt) + goto out_folio_put; break; } len -= ret; @@ -1407,7 +1399,20 @@ static int bio_iov_iter_bounce_read(struct bio *bio, struct iov_iter *iter, bvec_set_folio(&bio->bi_io_vec[0], folio, bio->bi_iter.bi_size, 0); if (iov_iter_extract_will_pin(iter)) bio_set_flag(bio, BIO_PAGE_PINNED); - return bio_iov_iter_align_down(bio, iter, minsize - 1); + + /* The first vec stores the bounce buffer, so do not subtract 1 here. */ + ret = bio_iov_iter_align_down(bio, iter, + &bio->bi_io_vec[bio->bi_vcnt], minsize - 1); + if (ret) + goto out_folio_put; + + /* Update the bounc buffer bv_len to the aligned down size. */ + bio->bi_io_vec[0].bv_len = bio->bi_iter.bi_size; + return 0; + +out_folio_put: + folio_put(folio); + return ret; } /** From 50dce2e2f84b56d8b4b406d97a1543709e8a87f5 Mon Sep 17 00:00:00 2001 From: Abhishek Ojha Date: Wed, 15 Jul 2026 13:04:08 -0400 Subject: [PATCH 38/41] regulator: ltc3676: Fix incorrect IRQSTAT bit offsets The LTC3676_IRQSTAT_* bit definitions do not match the IRQSTAT (Interrupt Request Status) register layout documented in Table 15 of the LTC3676/LTC3676-1 datasheet: bit 0 - Pushbutton Status Active bit 1 - Hard Reset Occurred bit 2 - PGOOD Timeout Occurred bit 3 - Undervoltage Warning bit 4 - Undervoltage Standby (Fault) Occurred bit 5 - Overtemperature Warning bit 6 - Overtemperature Standby (Fault) Occurred bit 7 - Reserved The driver instead defines these starting at bit 3, one bit higher than the datasheet specifies, which causes ltc3676_regulator_isr() to check the wrong status bits and misreport (or miss) PGOOD timeout, undervoltage and thermal warning/fault conditions. Fix the bit offsets to match the datasheet. Fixes: 37b918a034fe ("regulator: Add LTC3676 support") Cc: stable@vger.kernel.org Signed-off-by: Abhishek Ojha Link: https://patch.msgid.link/20260715170408.295552-1-Abhishek.ojha@savoirfairelinux.com Signed-off-by: Mark Brown --- drivers/regulator/ltc3676.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/regulator/ltc3676.c b/drivers/regulator/ltc3676.c index 73d511eb1c1dce..768cdce0d4ecfb 100644 --- a/drivers/regulator/ltc3676.c +++ b/drivers/regulator/ltc3676.c @@ -45,11 +45,11 @@ #define LTC3676_DVBxA_REF_SELECT BIT(5) #define LTC3676_DVBxB_PGOOD_MASK BIT(5) -#define LTC3676_IRQSTAT_PGOOD_TIMEOUT BIT(3) -#define LTC3676_IRQSTAT_UNDERVOLT_WARN BIT(4) -#define LTC3676_IRQSTAT_UNDERVOLT_FAULT BIT(5) -#define LTC3676_IRQSTAT_THERMAL_WARN BIT(6) -#define LTC3676_IRQSTAT_THERMAL_FAULT BIT(7) +#define LTC3676_IRQSTAT_PGOOD_TIMEOUT BIT(2) +#define LTC3676_IRQSTAT_UNDERVOLT_WARN BIT(3) +#define LTC3676_IRQSTAT_UNDERVOLT_FAULT BIT(4) +#define LTC3676_IRQSTAT_THERMAL_WARN BIT(5) +#define LTC3676_IRQSTAT_THERMAL_FAULT BIT(6) enum ltc3676_reg { LTC3676_SW1, From 8173f7e2ce67e6ca1d4763f3da14e5b01ce77456 Mon Sep 17 00:00:00 2001 From: "Cen Zhang (Microsoft)" Date: Tue, 7 Jul 2026 12:41:15 -0400 Subject: [PATCH 39/41] rhashtable: clear stale iter->p on table restart rhashtable_walk_start_check() has two restart paths when resuming a walk. When iter->walker.tbl is valid, it re-validates iter->p against the table and sets iter->p = NULL if the object is gone. When iter->walker.tbl is NULL (table was freed during resize), it resets slot and skip but forgets to clear iter->p. rhashtable_walk_next() then dereferences the stale iter->p, reading freed memory. This is a use-after-free. Any caller that does multi-fragment rhashtable walks across walk_stop/walk_start boundaries is affected. Concrete cases include netlink_diag (__netlink_diag_dump in net/netlink/diag.c) and TIPC (tipc_nl_sk_walk in net/tipc/socket.c). Crash stack (netlink_diag): BUG: KASAN: slab-use-after-free in rhashtable_walk_next+0x365/0x3c0 Read of size 8 at addr ffff88801a9d2438 (freed kmalloc-2k, offset 1080) Call Trace: rhashtable_walk_next+0x365/0x3c0 (lib/rhashtable.c:1016) __netlink_diag_dump+0x160/0x760 (net/netlink/diag.c:122) netlink_diag_dump+0xc2/0x240 netlink_dump+0x5bc/0x1270 netlink_recvmsg+0x7a3/0x980 sock_recvmsg+0x1bc/0x200 __sys_recvfrom+0x1d4/0x2c0 Fixes: 5d240a8936f6 ("rhashtable: improve rhashtable_walk stability when stop/start used.") Cc: Reported-by: AutonomousCodeSecurity@microsoft.com Reported-by: Yuan Tan Closes: https://lore.kernel.org/linux-crypto/CAB8m9Wh559e+=n8z51gB8DrbEyCc2mc0MgGjrRR6_VXBmU=2AQ@mail.gmail.com Signed-off-by: Cen Zhang (Microsoft) Reviewed-by: NeilBrown Signed-off-by: Herbert Xu --- lib/rhashtable.c | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 40cfb38ac919d2..d459bef245f4a7 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -878,6 +878,7 @@ int rhashtable_walk_start_check(struct rhashtable_iter *iter) iter->walker.tbl = rht_dereference_rcu(ht->tbl, ht); iter->slot = 0; iter->skip = 0; + iter->p = NULL; return -EAGAIN; } From 3afc64c61ce906a04f073ca350b46de10e8302f9 Mon Sep 17 00:00:00 2001 From: Woraphat Khiaodaeng Date: Fri, 17 Jul 2026 22:45:37 +0700 Subject: [PATCH 40/41] io_uring/bpf-ops: reject re-registration of an already-bound ops io_install_bpf() only rejects a second registration on the ctx side (ctx->bpf_ops) and sets the per-map back-pointer ops->priv unconditionally. The struct_ops link path never advances a map past BPF_STRUCT_OPS_STATE_READY, so the same io_uring_bpf_ops map can be registered more than once, and bpf_io_reg() re-resolves the target ring via fget(ops->ring_fd) on every call. A caller can therefore point the same ring_fd at a different io_ring_ctx between two BPF_LINK_CREATE calls. The second registration passes the ctx->bpf_ops check (the new ctx has none) and overwrites ops->priv, orphaning the first ctx. Teardown (io_eject_bpf()/bpf_io_unreg()) only reaches a ctx through ops->priv, so the orphaned ctx is never torn down: its ctx->loop_step keeps pointing into the struct_ops trampoline, which is freed once the map is gone. A later io_uring_enter() on the orphaned ring then calls the dangling ctx->loop_step from io_run_loop() -- a use-after-free of freed executable memory, reachable by a task with CAP_BPF + CAP_PERFMON. Reject registration when ops->priv is already set, as hid_bpf_reg() does for its struct_ops. Cc: stable@vger.kernel.org Fixes: 98f37634b12b ("io_uring/bpf-ops: implement bpf ops registration") Signed-off-by: Woraphat Khiaodaeng Reviewed-by: Gabriel Krisman Bertazi Reviewed-by: Pavel Begunkov Link: https://patch.msgid.link/20260717154537.129736-1-worapat.kd2@gmail.com Signed-off-by: Jens Axboe --- io_uring/bpf-ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/io_uring/bpf-ops.c b/io_uring/bpf-ops.c index 5a50f0675fe58f..cf2bd068e331b5 100644 --- a/io_uring/bpf-ops.c +++ b/io_uring/bpf-ops.c @@ -168,6 +168,8 @@ static int io_install_bpf(struct io_ring_ctx *ctx, struct io_uring_bpf_ops *ops) if (ctx->bpf_ops) return -EBUSY; + if (ops->priv) + return -EBUSY; if (WARN_ON_ONCE(!ops->loop_step)) return -EINVAL; From 1590cf0329716306e948a8fc29f1d3ee87d3989f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 19 Jul 2026 13:54:41 -0700 Subject: [PATCH 41/41] Linux 7.2-rc4 --- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index bfb47ad8cb9a74..11539c3fd405cc 100644 --- a/Makefile +++ b/Makefile @@ -2,7 +2,7 @@ VERSION = 7 PATCHLEVEL = 2 SUBLEVEL = 0 -EXTRAVERSION = -rc3 +EXTRAVERSION = -rc4 NAME = Baby Opossum Posse # *DOCUMENTATION*