[DEBUG]: iommu/arm-smmu: Track s2cr values in arm-smmu QCOM implement…#1
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…o SMMU On Kodiak platforms, the Adreno SMMU requires a bandwidth vote on the GEM_NOC path (MASTER_GPU_TCU -> SLAVE_EBI1) before its registers are accessible. Without this vote, the SMMU may become unreachable, leading to intermittent probe failures and runtime issues. Add the required interconnect to ensure reliable register access. Link: https://lore.kernel.org/all/20260526-smmu_interconnect_addition-v2-0-2a6d8ca30d63@oss.qualcomm.com/#t Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
…no SMMU On Lemans platforms, the Adreno SMMU requires a bandwidth vote on the GEM_NOC path (MASTER_GPU_TCU -> SLAVE_EBI1) before its registers are accessible. Without this vote, the SMMU may become unreachable, leading to intermittent probe failures and runtime issues. Add the required interconnect to ensure reliable register access. Link: https://lore.kernel.org/all/20260526-smmu_interconnect_addition-v2-0-2a6d8ca30d63@oss.qualcomm.com/#t Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
…no SMMU On Monaco platforms, the Adreno SMMU requires a bandwidth vote on the GEM_NOC path (MASTER_GPU_TCU -> SLAVE_EBI1) before its registers are accessible. Without this vote, the SMMU may become unreachable, leading to intermittent probe failures and runtime issues. Add the required interconnect to ensure reliable register access. Link: https://lore.kernel.org/all/20260526-smmu_interconnect_addition-v2-0-2a6d8ca30d63@oss.qualcomm.com/#t Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
…o SMMU On Talos platforms, the Adreno SMMU requires a bandwidth vote on the GEM_NOC path (MASTER_GPU_TCU -> SLAVE_EBI1) before its registers are accessible. Without this vote, the SMMU may become unreachable, leading to intermittent probe failures and runtime issues. Add the required interconnect to ensure reliable register access. Link: https://lore.kernel.org/all/20260526-smmu_interconnect_addition-v2-0-2a6d8ca30d63@oss.qualcomm.com/#t Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
…ation Debug patch to trakc the reads and writes from arm-smmu's s2cr implementation. Signed-off-by: Bibek Kumar Patro <bibek.patro@oss.qualcomm.com>
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__team_change_mode() clears team->ops with memset() before restoring safe dummy handlers via team_adjust_ops(). A concurrent team_xmit() running under RCU on another CPU can read team->ops.transmit during this window and call a NULL function pointer, crashing the kernel. The race requires a mode change (CAP_NET_ADMIN) concurrent with transmit on the team device. BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: 0010 [#1] SMP KASAN NOPTI RIP: 0010:0x0 Call Trace: team_xmit (drivers/net/team/team_core.c:1853) dev_hard_start_xmit (net/core/dev.c:3904) __dev_queue_xmit (net/core/dev.c:4871) packet_sendmsg (net/packet/af_packet.c:3109) __sys_sendto (net/socket.c:2265) The original code assumed that no ports means no traffic, so mode changes could freely memset()/memcpy() the ops. AF_PACKET with forced carrier breaks that assumption. Prevent the race instead of making it safe: replace memset()/memcpy() with per-field updates that never touch transmit or receive. Those two handlers are managed solely by team_adjust_ops(), which already installs dummies when tx_en_port_count == 0 (always true during mode change since no ports are present). WRITE_ONCE/READ_ONCE prevent store/load tearing on the handler pointers. synchronize_net() before exit_op() drains in-flight readers that may still reference old mode state from before port removal switched the handlers to dummies. Fixes: 3d249d4 ("net: introduce ethernet teaming device") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Link: https://patch.msgid.link/20260521081159.1491563-3-bestswngs@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Since the introduction of the netlink configuration path for bridge ports in commit 25c71c7 ("bridge: bridge port parameters over netlink"), br_setport() was always called with the bridge lock held around it. Back then this decision made sense: The bridge lock protects the STP state of the bridge and its ports and at that time the function only processed three STP related netlink attributes (cost, priority and state). Nowadays, br_setport() processes a lot more attributes and most of them do not need the bridge lock: * Bridge flags: Only require RTNL. Read locklessly by the data path. Annotations can be added in net-next. * FDB port flushing: Only requires the FDB lock. * Multicast attributes: Only require the multicast lock. * Group forward mask: Only requires RTNL. Read locklessly by the data path. Annotations can be added in net-next. * Backup port and NHID: Only require RTNL. Read locklessly by the data path. This is a problem as the bridge calls dev_set_promiscuity() when certain bridge port flags change and this function can sleep since the commit cited below, resulting in a splat such as [1]. Fix this by reducing the scope of the bridge lock and only take it when processing the three STP related attributes that require it. This is consistent with the multicast attributes where each attribute acquires the multicast lock instead of having one critical section for all relevant attributes. [1] BUG: sleeping function called from invalid context at net/core/dev_addr_lists.c:1262 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 356, name: bridge preempt_count: 201, expected: 0 RCU nest depth: 0, expected: 0 2 locks held by bridge/356: #0: ffffffff919473a0 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg (net/core/rtnetlink.c:80 net/core/rtnetlink.c:7002) #1: ffff888115072d58 (&br->lock){+...}-{3:3}, at: br_setlink (./include/linux/spinlock.h:348 net/bridge/br_netlink.c:1117) Preemption disabled at: 0x0 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120) __might_resched.cold (kernel/sched/core.c:9163) netif_rx_mode_run (net/core/dev_addr_lists.c:1262) netif_rx_mode_sync (net/core/dev_addr_lists.c:1428) dev_set_promiscuity (net/core/dev_api.c:289) br_manage_promisc (net/bridge/br_if.c:135 net/bridge/br_if.c:172) br_port_flags_change (net/bridge/br_if.c:242 net/bridge/br_if.c:747) br_setport (net/bridge/br_netlink.c:1000) br_setlink (net/bridge/br_netlink.c:1118) rtnl_bridge_setlink (net/core/rtnetlink.c:5572) rtnetlink_rcv_msg (net/core/rtnetlink.c:7005) netlink_rcv_skb (net/netlink/af_netlink.c:2550) netlink_unicast (net/netlink/af_netlink.c:1318 net/netlink/af_netlink.c:1344) netlink_sendmsg (net/netlink/af_netlink.c:1894) __sock_sendmsg (net/socket.c:787 (discriminator 4) net/socket.c:802 (discriminator 4)) ____sys_sendmsg (net/socket.c:2698) ___sys_sendmsg (net/socket.c:2752) __sys_sendmsg (net/socket.c:2784) do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) Fixes: 78cd408 ("net: add missing instance lock to dev_set_promiscuity") Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260526064818.272516-2-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Since the start of the git history, brport_store() always acquired the
bridge lock. Back then this decision made sense: The bridge lock
protects the STP state of the bridge and its ports and at that time the
function was only used by two STP related attributes (cost and
priority).
Nowadays, brport_store() processes a lot more attributes and most of
them do not need the bridge lock:
* Bridge flags: Only require RTNL. Read locklessly by the data path.
Annotations can be added in net-next.
* FDB port flushing: Only requires the FDB lock.
* Multicast attributes: Only require the multicast lock.
* Group forward mask: Only requires RTNL. Read locklessly by the data
path. Annotations can be added in net-next.
* Backup port: Only requires RTNL. Read locklessly by the data path.
This is a problem as the bridge calls dev_set_promiscuity() when certain
bridge port flags change and this function can sleep since the commit
cited below, resulting in a splat such as [1].
Fix this by reducing the scope of the bridge lock and only take it when
processing the two STP related attributes that require it. Remove the
now stale comment from br_switchdev_set_port_flag(). The
SWITCHDEV_F_DEFER flag can be removed in net-next.
[1]
BUG: sleeping function called from invalid context at net/core/dev_addr_lists.c:1262
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 372, name: bash
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
5 locks held by bash/372:
#0: ffff88810c51c3f0 (sb_writers#7){.+.+}-{0:0}, at: ksys_write (fs/read_write.c:740)
#1: ffff888115ce9480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter (fs/kernfs/file.c:343)
qualcomm-linux#2: ffff88810b9fd330 (kn->active#37){.+.+}-{0:0}, at: kernfs_fop_write_iter (fs/kernfs/file.c:80 fs/kernfs/file.c:344)
qualcomm-linux#3: ffffffffa59473a0 (rtnl_mutex){+.+.}-{4:4}, at: brport_store (net/bridge/br_sysfs_if.c:326)
qualcomm-linux#4: ffff8881099d2d58 (&br->lock){+...}-{3:3}, at: brport_store (./include/linux/spinlock.h:348 net/bridge/br_sysfs_if.c:345)
Preemption disabled at:
0x0
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
__might_resched.cold (kernel/sched/core.c:9163)
netif_rx_mode_run (net/core/dev_addr_lists.c:1262)
netif_rx_mode_sync (net/core/dev_addr_lists.c:1428)
dev_set_promiscuity (net/core/dev_api.c:289)
br_manage_promisc (net/bridge/br_if.c:135 net/bridge/br_if.c:172)
br_port_flags_change (net/bridge/br_if.c:242 net/bridge/br_if.c:747)
store_learning (net/bridge/br_sysfs_if.c:79 net/bridge/br_sysfs_if.c:235)
brport_store (net/bridge/br_sysfs_if.c:346)
kernfs_fop_write_iter (fs/kernfs/file.c:352)
new_sync_write (fs/read_write.c:595)
vfs_write (fs/read_write.c:688)
ksys_write (fs/read_write.c:740)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Fixes: 78cd408 ("net: add missing instance lock to dev_set_promiscuity")
Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260526064818.272516-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Ido Schimmel says: ==================== bridge: Fix sleep in atomic context Under certain circumstances the bridge driver can call dev_set_promiscuity() while holding the bridge spin lock. This is a problem as dev_set_promiscuity() might sleep. Patches #1-qualcomm-linux#2 fix the problem in the netlink and sysfs configuration paths by only taking the lock where it is actually needed, thereby avoiding calling dev_set_promiscuity() from an atomic context. Patch qualcomm-linux#3 adds test cases for both configuration paths in rtnetlink.sh which already includes test cases for similar issues. Note that dev_set_promiscuity() can sleep either when it takes the net device mutex or when calling netif_rx_mode_sync(). I encountered the problem with the latter, but blamed the former since it came earlier. ==================== Link: https://patch.msgid.link/20260526064818.272516-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…k overflow tcf_mirred_act() checks sched_mirred_nest against MIRRED_NEST_LIMIT (4) to prevent deep recursion. However, when the action uses blockcast (tcfm_blockid != 0), the function returns at the tcf_blockcast() call BEFORE reaching the counter increment. As a result, the recursion counter never advances and the limit check is entirely bypassed. When two devices share a TC egress block with a mirred blockcast rule, a packet egressing on device A is mirrored to device B via blockcast; device B's egress TC re-enters tcf_mirred_act() via blockcast and mirrors back to A, creating an unbounded recursion loop: tcf_mirred_act -> tcf_blockcast -> tcf_mirred_to_dev -> dev_queue_xmit -> sch_handle_egress -> tcf_classify -> tcf_mirred_act -> (repeat) This recursion continues until the kernel stack overflows. The bug is reachable from an unprivileged user via unshare(CLONE_NEWUSER | CLONE_NEWNET): user namespaces grant CAP_NET_ADMIN in the new network namespace, which is sufficient to create dummy devices, attach clsact qdiscs with shared blocks, and install mirred blockcast filters. BUG: TASK stack guard page was hit at ffffc90000b7fff8 Oops: stack guard page: 0000 [#1] SMP KASAN NOPTI CPU: 2 UID: 1000 PID: 169 Comm: poc Not tainted 7.0.0-rc7-next-20260410 RIP: 0010:xas_find+0x17/0x480 Call Trace: xa_find+0x17b/0x1d0 tcf_mirred_act+0x640/0x1060 tcf_action_exec+0x400/0x530 basic_classify+0x128/0x1d0 tcf_classify+0xd83/0x1150 tc_run+0x328/0x620 __dev_queue_xmit+0x797/0x3100 tcf_mirred_to_dev+0x7b1/0xf70 tcf_mirred_act+0x68a/0x1060 [repeating ~30+ times until stack overflow] Kernel panic - not syncing: Fatal exception in interrupt Fix this by incrementing sched_mirred_nest before calling tcf_blockcast() and decrementing it on return, mirroring the non-blockcast path. This ensures subsequent recursive entries see the updated counter and are correctly limited by MIRRED_NEST_LIMIT. Fixes: fe946a7 ("net/sched: act_mirred: add loop detection") Signed-off-by: Kito Xu (veritas501) <hxzene@gmail.com> Link: https://patch.msgid.link/20260525122556.973584-7-jhs@mojatatu.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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TLDR: The bo->ttm object might be changed by calling ttm_bo_validate(),
move casting it to an i915_tt object later to actually get the right
pointer.
A user reported hitting the following bug under heavy use on DG2:
[26620.095550] Oops: general protection fault, probably for non-canonical address 0xa56b6b6b6b6b6b8b: 0000 1 SMP NOPTI
[26620.095556] CPU: 2 UID: 0 PID: 631 Comm: Xorg Not tainted 6.18.8 #1 PREEMPT(lazy)
[26620.095558] Hardware name: ASRock B850M Steel Legend WiFi/B850M Steel Legend WiFi, BIOS 3.50 09/18/2025
[26620.095559] RIP: 0010:i915_ttm_purge+0x84/0x100 [i915]
[26620.095604] Code: 00 00 00 48 8d 54 24 10 48 89 e6 48 89 fb e8 83 aa ae ff 85 c0 75 6f 48 83 bb a8 01 00 00 00 74 2c 48 8b 45 78 48 85 c0 74 23 <48> 8b 78 20 48 c7 c2 ff ff ff ff 31 f6 e8 7a 73 e3 e0 48 8b 7d 78
[26620.095605] RSP: 0018:ffffc90005fd7430 EFLAGS: 00010282
[26620.095607] RAX: a56b6b6b6b6b6b6b RBX: ffff8881f46c3dc0 RCX: 0000000000000000
[26620.095608] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 00000000ffffffff
[26620.095609] RBP: ffff888289610f00 R08: 0000000000000001 R09: ffff88823b022000
[26620.095609] R10: ffff888103029b28 R11: ffff8881fc7f3800 R12: ffff88810b6150d0
[26620.095609] R13: ffff888289610f00 R14: 0000000000000000 R15: ffff8881f46c3dc0
[26620.095610] FS: 00007f1004d86900(0000) GS:ffff88901c858000(0000) knlGS:0000000000000000
[26620.095611] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[26620.095611] CR2: 00007f0fdf489000 CR3: 000000035b0c1000 CR4: 0000000000750ef0
[26620.095612] PKRU: 55555554
[26620.095612] Call Trace:
[26620.095615] <TASK>
[26620.095615] i915_ttm_move+0x2b9/0x420 [i915]
[26620.095642] ? ttm_tt_init+0x65/0x80 [ttm]
[26620.095644] ? i915_ttm_tt_create+0xc6/0x150 [i915]
[26620.095667] ttm_bo_handle_move_mem+0xb6/0x160 [ttm]
[26620.095669] ttm_bo_evict+0x100/0x150 [ttm]
[26620.095671] ? preempt_count_add+0x64/0xa0
[26620.095673] ? _raw_spin_lock+0xe/0x30
[26620.095675] ? _raw_spin_unlock+0xd/0x30
[26620.095675] ? i915_gem_object_evictable+0xb7/0xd0 [i915]
[26620.095704] ttm_bo_evict_cb+0x6e/0xd0 [ttm]
[26620.095705] ttm_lru_walk_for_evict+0xa6/0x200 [ttm]
[26620.095708] ttm_bo_alloc_resource+0x185/0x4f0 [ttm]
[26620.095709] ? init_object+0x62/0xd0
[26620.095712] ttm_bo_validate+0x7a/0x180 [ttm]
[26620.095713] ? _raw_spin_unlock_irqrestore+0x16/0x30
[26620.095714] __i915_ttm_get_pages+0xb0/0x170 [i915]
[26620.095737] i915_ttm_get_pages+0x9f/0x150 [i915]
[26620.095759] ? i915_gem_do_execbuffer+0xedc/0x2b40 [i915]
[26620.095786] ? alloc_debug_processing+0xd0/0x100
[26620.095787] ? _raw_spin_unlock_irqrestore+0x16/0x30
[26620.095788] ? i915_vma_instance+0xa0/0x4e0 [i915]
[26620.095822] __i915_gem_object_get_pages+0x2f/0x40 [i915]
[26620.095848] i915_vma_pin_ww+0x706/0x980 [i915]
[26620.095875] ? i915_gem_do_execbuffer+0xedc/0x2b40 [i915]
[26620.095904] eb_validate_vmas+0x170/0xa00 [i915]
[26620.095930] i915_gem_do_execbuffer+0x1201/0x2b40 [i915]
[26620.095953] ? alloc_debug_processing+0xd0/0x100
[26620.095954] ? _raw_spin_unlock_irqrestore+0x16/0x30
[26620.095955] ? i915_gem_execbuffer2_ioctl+0xc9/0x240 [i915]
[26620.095977] ? __wake_up_sync_key+0x32/0x50
[26620.095979] ? i915_gem_execbuffer2_ioctl+0xc9/0x240 [i915]
[26620.096001] ? __slab_alloc.isra.0+0x67/0xc0
[26620.096003] i915_gem_execbuffer2_ioctl+0x11a/0x240 [i915]
Results from decode_stacktrace.sh pointed to dereference of a file pointer
field of a i915 TTM page vector container associated with an object being
purged on eviction. That path is taken when the object is marked as no
longer needed.
Code analysis revealed a possibility of the i915 TTM page vector container
being replaced with a new instance inside a function that purges content
of the object, should it be still busy. That function is called,
indirectly via a more general function that changes the object's placement
and caching policy, before the problematic dereference, but still after
a pointer to the container is captured, rendering the pointer no longer
valid.
Fix the issue by capturing the pointer to the container only after its
potential replacement.
v2: Move the container_of() inside the if block (Sebastian),
- a simplified version of the commit description that explains briefly
why the change is necessary (Christian).
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/work_items/14882
Fixes: 7ae0345 ("drm/i915/ttm: add tt shmem backend")
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: stable@vger.kernel.org # v5.17+
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Sebastian Brzezinka <sebastian.brzezinka@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://lore.kernel.org/r/20260508122612.469227-2-janusz.krzysztofik@linux.intel.com
(cherry picked from commit 4462966)
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
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Prevent a crash from happening as the first serial port is initialised: Console: switching to colour frame buffer device 160x64 tgafb: SFB+ detected, rev=0x02 fb0: Digital ZLX-E1 frame buffer device at 0x1e000000 DECstation DZ serial driver version 1.04 CPU 0 Unable to handle kernel paging request at virtual address 000000bc, epc == 8048b3a4, ra == 80470a78 Oops[#1]: CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.19.0-dirty qualcomm-linux#35 NONE $ 0 : 00000000 1000ac00 00000004 804707ac $ 4 : 00000000 80e20850 80e20858 81000030 $ 8 : 00000000 8072c81c 00000008 fefefeff $12 : 6c616972 00000006 80c5917f 69726420 $16 : 80e20800 00000000 808f8968 80e20800 $20 : 00000000 807f5a9 808b0094 808d3bc8 $24 : 00000018 80479030 $28 : 80c2e000 80c2fd70 00000069 80470a78 Hi : 00000004 Lo : 00000000 epc : 8048b3a4 __dev_fwnode+0x0/0xc ra : 80470a78 serial_base_ctrl_add+0xa0/0x168 Status: 1000ac04 IEp Cause : 30000008 (ExcCode 02) BadVA : 000000bc PrId : 00000220 (R3000) Modules linked in: Process swapper/0 (pid: 1, threadinfo=(ptrval), task=(ptrval), tls=00000000) Stack : 00400044 00400040 8046f4cc 00000000 808a6148 808a0000 808f8968 8086983c 808e0000 8046fc84 1000ac01 00000028 80e20700 802ba3f8 80e20700 80d34a94 80c1b900 80e20700 80e20700 80e20700 80e20700 80444650 00000000 00000000 00000000 807f5a9 808b0094 80447080 00400040 808e0000 80d34a94 808a6148 80d34a94 00000004 80e20700 00000000 8076974c 80469810 80c2fe3c 1000ac01 ... Call Trace: [<8048b3a4>] __dev_fwnode+0x0/0xc [<80470a78>] serial_base_ctrl_add+0xa0/0x168 [<8046fc84>] serial_core_register_port+0x1c8/0x974 [<808c6af0>] dz_init+0x74/0xc8 [<800470e0>] do_one_initcall+0x44/0x2d4 [<808b111c>] kernel_init_freeable+0x258/0x308 [<8072e434>] kernel_init+0x20/0x114 [<80049cd0>] ret_from_kernel_thread+0x14/0x1c Code: 27bd0018 03e00008 2402ffea <8c8200bc> 03e00008 00000000 27bdffc0 afbe0038 afb30024 ---[ end trace 0000000000000000 ]--- -- where a pointer is dereferenced that has been derived from a null pointer to the port's parent device. Since no device is available with legacy probing and it's not anymore a preferable way to discover devices anyway, switch the driver to using a platform device and use it as the port's parent device. Update resource handling accordingly and only request the actual span of addresses used within the slot, which will have had its resource already requested by generic platform device code. Use platform_driver_probe() not just because the DZ device is fixed with solder on board and not straightforward to remove, but foremost because the associated TTY's major device number is the same as used by the zs driver and the first driver to claim it will prevent the other one from using it. Either one DZ device or some SCC devices will be present in a given system but never both at a time, and therefore we want the major device number to be claimed by the first driver to actually successfully bind to its device and platform_driver_probe() is a way to fulfil that. An unfortunate consequence of the switch to a platform device is we now hand the console over from the bootconsole much later in the bootstrap. The firmware console handler appears good enough though to work so late and in particular with interrupts enabled. Conversely only starting the console port so late lets the reset code fully utilise our delay handlers, so switch from udelay() to fsleep() for transmitter draining so as to avoid busy-waiting for an excessive amount of time. Fixes: 84a9582 ("serial: core: Start managing serial controllers to enable runtime PM") Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Cc: stable@vger.kernel.org # needs to use .remove_new for <= 6.10 Link: https://patch.msgid.link/alpine.DEB.2.21.2605062326540.46195@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Prevent a crash from happening as the first serial port is initialised: Console: switching to mono frame buffer device 160x64 fb0: PMAG-AA frame buffer device at tc0 DECstation Z85C30 serial driver version 0.10 CPU 0 Unable to handle kernel paging request at virtual address 0000002c, epc == 803ab00c, ra == 803aafe0 Oops[#1]: CPU: 0 PID: 1 Comm: swapper Not tainted 6.4.0-rc3-00031-g84a9582fd203-dirty qualcomm-linux#57 $ 0 : 00000000 10012c00 803aaeb0 00000000 $ 4 : 80e12f60 80e12f50 80e12f58 81000030 $ 8 : 00000000 805ff37c 00000000 33433538 $12 : 65732030 00000006 80c2915d 6c616972 $16 : 80e12f00 807b7630 00000000 00000000 $20 : 00000004 00000348 000001a0 807623b8 $24 : 00000018 00000000 $28 : 80c24000 80c25d60 8078b148 803aafe0 Hi : 00000000 Lo : 00000000 epc : 803ab00c serial_base_ctrl_add+0x78/0xf4 ra : 803aafe0 serial_base_ctrl_add+0x4c/0xf4 Status: 10012c03 KERNEL EXL IE Cause : 00000008 (ExcCode 02) BadVA : 0000002c PrId : 00000440 (R4400SC) Modules linked in: Process swapper (pid: 1, threadinfo=(ptrval), task=(ptrval), tls=00000000) Stack : 80760000 00000cc0 00400044 00400040 803aa02c 80d61ab8 00000000 807b7630 80760000 807623b8 807b7628 803aa644 80386998 00000000 80e17780 80220f68 80e17780 80d61ab8 80c17d80 80e17780 80e17780 8063c798 80e17780 80383fa0 00000010 80e17780 00000000 80386998 807a0000 00000000 00400040 8038f848 807623b8 80d61ab8 00000004 80e17780 00000000 803a68e4 80c25e2c 803bb884 ... Call Trace: [<803ab00c>] serial_base_ctrl_add+0x78/0xf4 [<803aa644>] serial_core_register_port+0x174/0x69c [<8077e9ac>] zs_init+0xc8/0xfc [<800404d4>] do_one_initcall+0x40/0x2ac [<8076cecc>] kernel_init_freeable+0x1e4/0x270 [<80605bec>] kernel_init+0x20/0x108 [<800431e8>] ret_from_kernel_thread+0x14/0x1c Code: 2442aeb0 ae120024 ae0200d0 <8c67002c> 50e00001 8c670000 3c06806 3c05806e afb30010 ---[ end trace 0000000000000000 ]--- (report at the offending commit) -- where a pointer is dereferenced that has been derived from a null pointer to the port's parent device. Since no device is available with legacy probing and it's not anymore a preferable way to discover devices anyway, switch the driver to using a platform device and use it as the port's parent device. Update resource handling accordingly and only request the actual span of addresses used within the slot, which will have had its resource already requested by generic platform device code. Use platform_driver_probe() not just because SCC devices are fixed with solder on board and not straightforward to remove, but foremost because the associated TTY's major device number is the same as used by the dz driver and the first driver to claim it will prevent the other one from using it. Either one DZ device or some SCC devices will be present in a given system but never both at a time, and therefore we want the major device number to be claimed by the first driver to actually successfully bind to its device and platform_driver_probe() is a way to fulfil that. An unfortunate consequence of the switch to a platform device is we now hand the console over from the bootconsole much later in the bootstrap. The firmware console handler appears good enough though to work so late and in particular with interrupts enabled. Since there is one way only remaining to reach zs_reset() now, remove the port initialisation marker as no longer needed and go through the channel reset unconditionally. Fixes: 84a9582 ("serial: core: Start managing serial controllers to enable runtime PM") Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Cc: stable@vger.kernel.org # needs to use .remove_new for <= 6.10 Link: https://patch.msgid.link/alpine.DEB.2.21.2605062328480.46195@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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With CONFIG_CALL_DEPTH_TRACKING enabled on an x86 retbleed-affected platform (eg: Skylake), with retbleed=stuff, registering a dynamic ftrace trampoline crashes on the first call into the traced function: BUG: unable to handle page fault for address: ffff88817ae18880 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 4b53067 P4D 4b53067 PUD 0 Oops: Oops: 0002 [#1] SMP PTI CPU: 3 UID: 0 PID: 187 Comm: usleep Not tainted 7.0.10 qualcomm-linux#243 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.17.0-2-2 04/01/2014 Code: 24 78 00 00 00 00 48 89 ea 48 89 54 24 20 48 8b b4 24 b8 00 00 00 48 8b bc 24 b0 00 00 00 48 89 bc 24 80 00 00 00 48 83 ef 05 <65> 48 c1 3d 1f a8 b6 02 05 48 8b 15 f6 00 00 00 4c 89 3c 24 4c 89 Call Trace: <TASK> ? find_held_lock ? exc_page_fault ? lock_release ? __x64_sys_clock_nanosleep ? lockdep_hardirqs_on_prepare ? trace_hardirqs_on __x64_sys_clock_nanosleep do_syscall_64 ? exc_page_fault ? call_depth_return_thunk entry_SYSCALL_64_after_hwframe ... Kernel panic - not syncing: Fatal exception This small reproducer allows to easily trigger the crash: # echo 'p __x64_sys_clock_nanosleep' > /sys/kernel/tracing/kprobe_events # echo 1 > /sys/kernel/tracing/events/kprobes/p___x64_sys_clock_nanosleep_0/enable # usleep 1 Monitoring the crash under GDB points to the exact instruction in charge of incrementing the call depth: sarq $5, %gs:__x86_call_depth(%rip) This instruction matches the one inserted by the ftrace_regs_caller from ftrace_64.S. This emitted code was likely working fine until the introduction of 59bec00 ("x86/percpu: Introduce %rip-relative addressing to PER_CPU_VAR()"): it has made the call depth accounting addressing relative to $rip, instead of being based on an absolute address. As this code exact location depends on where the trampoline lives in memory, the corresponding displacement needs to be adjusted at runtime to actually correctly find the per-cpu __x86_call_depth value, otherwise the targeted address is wrong, leading to the page fault seen above. Fix the %rip-relative displacement of the copied CALL_DEPTH_ACCOUNT instruction (from ftrace_regs_caller) by calling text_poke_apply_relocation(), as it is done for example by the x86 BPF JIT compiler through x86_call_depth_emit_accounting(). This corrects both CALL_DEPTH_ACCOUNT slots, in ftrace_caller and ftrace_regs_caller. [ bp: Massage. ] Fixes: 59bec00 ("x86/percpu: Introduce %rip-relative addressing to PER_CPU_VAR()") Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@bootlin.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: <stable@kernel.org> Link: https://patch.msgid.link/20260527-fix_call_depth_in_trampoline-v1-1-1c1abc8ae310@bootlin.com
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On the UDP receive path skb->dev is repurposed as dev_scratch (the
truesize/state cache set by udp_set_dev_scratch()), through the
union { struct net_device *dev; unsigned long dev_scratch; } in sk_buff.
When a UDP socket is in a sockmap, sk_data_ready is
sk_psock_verdict_data_ready(), which calls udp_read_skb() -> recv_actor()
(sk_psock_verdict_recv) to run the attached SK_SKB verdict program in softirq.
If that program calls a socket-lookup helper (bpf_sk_lookup_tcp/udp,
bpf_skc_lookup_tcp), bpf_skc_lookup() does:
if (skb->dev)
caller_net = dev_net(skb->dev);
skb->dev still holds the dev_scratch value (a non-NULL integer), so dev_net()
dereferences it as a struct net_device * and the kernel takes a general
protection fault on a non-canonical address in softirq:
Oops: general protection fault, probably for non-canonical address 0x1010000800004a0
CPU: 1 UID: 0 PID: 1406 Comm: syz.2.19 Not tainted 7.1.0-rc6 #1 PREEMPT(full)
RIP: 0010:bpf_skc_lookup net/core/filter.c:7033 [inline]
RIP: 0010:bpf_sk_lookup+0x45/0x160 net/core/filter.c:7047
Call Trace:
<IRQ>
bpf_prog_4675cb904b7071f8+0x12e/0x14e
bpf_prog_run_pin_on_cpu+0xc6/0x1f0
sk_psock_verdict_recv+0x1ba/0x350
udp_read_skb+0x31a/0x370
sk_psock_verdict_data_ready+0x2e3/0x600
__udp_enqueue_schedule_skb+0x4c8/0x650
udpv6_queue_rcv_one_skb+0x3ec/0x740
udp6_unicast_rcv_skb+0x11d/0x140
ip6_protocol_deliver_rcu+0x61e/0x950
ip6_input_finish+0xa9/0x150
NF_HOOK+0x286/0x2f0
ip6_input+0x117/0x220
NF_HOOK+0x286/0x2f0
__netif_receive_skb+0x85/0x200
process_backlog+0x374/0x9a0
__napi_poll+0x4f/0x1c0
net_rx_action+0x3b0/0x770
handle_softirqs+0x15a/0x460
do_softirq+0x57/0x80
</IRQ>
The rmem charge that dev_scratch accounted for is released by skb_recv_udp() on
dequeue, just above, so the scratch is dead by the time recv_actor() runs. Clear
skb->dev so bpf_skc_lookup() falls back to sock_net(skb->sk), which
skb_set_owner_sk_safe() set just above.
Fixes: 965b57b ("net: Introduce a new proto_ops ->read_skb()")
Cc: stable@vger.kernel.org
Signed-off-by: Sechang Lim <rhkrqnwk98@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260603162737.697215-1-rhkrqnwk98@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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mvebu_pwm_suspend() and mvebu_pwm_resume() are called for all GPIO banks during suspend/resume, but not all banks have PWM functionality. GPIO banks without PWM have mvchip->mvpwm set to NULL. Calling mvebu_pwm_suspend() with mvpwm == NULL causes a NULL pointer dereference when it tries to access mvpwm->blink_select. Unable to handle kernel NULL pointer dereference at virtual address 00000020 when write [00000020] *pgd=00000000 Internal error: Oops: 815 [#1] PREEMPT ARM Modules linked in: CPU: 0 UID: 0 PID: 406 Comm: sh Not tainted 6.12.74-rt12-yocto-standard-g4e96f98fb7db-dirty qualcomm-linux#353 Hardware name: Marvell Armada 370/XP (Device Tree) PC is at regmap_mmio_read+0x38/0x54 LR is at regmap_mmio_read+0x38/0x54 pc : [<c05fd2ac>] lr : [<c05fd2ac>] psr: 200f0013 sp : f0c11d10 ip : 00000000 fp : c100d2f0 r10: c14fb854 r9 : 00000000 r8 : 00000000 r7 : c1799c00 r6 : 00000020 r5 : 00000020 r4 : c179c7c0 r3 : f0a231a0 r2 : 00000020 r1 : 00000020 r0 : 00000000 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 135ec059 DAC: 00000051 Call trace: regmap_mmio_read from _regmap_bus_reg_read+0x78/0xac _regmap_bus_reg_read from _regmap_read+0x60/0x154 _regmap_read from regmap_read+0x3c/0x60 regmap_read from mvebu_gpio_suspend+0xa4/0x14c mvebu_gpio_suspend from dpm_run_callback+0x54/0x180 dpm_run_callback from device_suspend+0x124/0x630 device_suspend from dpm_suspend+0x124/0x270 dpm_suspend from dpm_suspend_start+0x64/0x6c dpm_suspend_start from suspend_devices_and_enter+0x140/0x8e8 suspend_devices_and_enter from pm_suspend+0x2fc/0x308 pm_suspend from state_store+0x6c/0xc8 state_store from kernfs_fop_write_iter+0x10c/0x1f8 kernfs_fop_write_iter from vfs_write+0x270/0x468 vfs_write from ksys_write+0x70/0xf0 ksys_write from ret_fast_syscall+0x0/0x54 Add a NULL check for mvchip->mvpwm before calling the PWM suspend/resume functions. Fixes: 757642f ("gpio: mvebu: Add limited PWM support") Signed-off-by: Yun Zhou <yun.zhou@windriver.com> Link: https://patch.msgid.link/20260608084334.2960803-1-yun.zhou@windriver.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
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mlx5_query_nic_vport_mac_list() sizes its firmware command buffer using the PF's log_max_current_uc/mc_list capabilities. When querying a VF vport with a larger configured max (via devlink), the firmware response can overflow this buffer: BUG: KASAN: slab-out-of-bounds in mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] Read of size 4 at addr ff1100013ffc8a12 by task kworker/u96:2/385 CPU: 12 UID: 0 PID: 385 Comm: kworker/u96:2 Not tainted 7.0.0-rc6+ #1 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009) Workqueue: mlx5_esw_wq esw_vport_change_handler [mlx5_core] Call Trace: <TASK> dump_stack_lvl+0x69/0xa0 print_report+0x176/0x4e4 kasan_report+0xc8/0x100 mlx5_query_nic_vport_mac_list+0x453/0x4c0 [mlx5_core] esw_update_vport_addr_list+0x2e3/0xda0 [mlx5_core] esw_vport_change_handle_locked+0xa1f/0x1060 [mlx5_core] esw_vport_change_handler+0x6a/0x90 [mlx5_core] process_one_work+0x87f/0x15e0 worker_thread+0x62b/0x1020 kthread+0x375/0x490 ret_from_fork+0x4dc/0x810 ret_from_fork_asm+0x11/0x20 </TASK> Fix by querying the vport's own HCA caps to size the buffer correctly. Refactor the function to allocate and return the MAC list internally, removing the caller's dependency on knowing the correct max. Fixes: e16aea2 ("net/mlx5: Introduce access functions to modify/query vport mac lists") Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com> Reviewed-by: Carolina Jubran <cjubran@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Link: https://patch.msgid.link/20260604135849.458060-1-tariqt@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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… completion rds_ib_xmit_atomic() always programs a masked atomic opcode (IB_WR_MASKED_ATOMIC_CMP_AND_SWP or IB_WR_MASKED_ATOMIC_FETCH_AND_ADD) for every RDS atomic cmsg. But the completion-side switch in rds_ib_send_unmap_op() only handles the non-masked opcodes, so a masked atomic completion falls through to default and returns rm == NULL while send->s_op is left set. rds_ib_send_cqe_handler() then dereferences the NULL rm via rm->m_final_op, oopsing in softirq context. An unprivileged AF_RDS sendmsg() of an atomic cmsg over an active RDS/IB connection triggers it; on hardware that natively accepts masked atomics (mlx4, mlx5) no extra setup is needed. RDS/IB: rds_ib_send_unmap_op: unexpected opcode 0xd in WR! Oops: general protection fault [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000190-0x0000000000000197] RIP: rds_ib_send_cqe_handler+0x25c/0xb10 (net/rds/ib_send.c:282) Call Trace: <IRQ> rds_ib_send_cqe_handler (net/rds/ib_send.c:282) poll_scq (net/rds/ib_cm.c:274) rds_ib_tasklet_fn_send (net/rds/ib_cm.c:294) tasklet_action_common (kernel/softirq.c:943) handle_softirqs (kernel/softirq.c:573) run_ksoftirqd (kernel/softirq.c:479) </IRQ> Kernel panic - not syncing: Fatal exception in interrupt Handle the masked atomic opcodes in the same case as the non-masked ones: they map to the same struct rds_message.atomic union member, so the existing container_of()/rds_ib_send_unmap_atomic() body is correct for them. Fixes: 20c72bd ("RDS: Implement masked atomic operations") Reported-by: Xiang Mei <xmei5@asu.edu> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Reviewed-by: Allison Henderson <achender@kernel.org> Link: https://patch.msgid.link/20260606192447.1179255-2-bestswngs@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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addrconf_get_prefix_route() can return the fib6_null_entry sentinel entry which has a NULL fib6_table pointer. Therefore, before setting the route's expiration time, check that we are not working with this entry, as otherwise a NPD will be triggered [1]. Note that the other callers of addrconf_get_prefix_route() are not susceptible to this bug: 1. addrconf_prefix_rcv(): Requests a route with the 'RTF_ADDRCONF | RTF_PREFIX_RT' flags which are not set on fib6_null_entry. 2. modify_prefix_route(): Fixed by commit a747e02 ("ipv6: avoid possible NULL deref in modify_prefix_route()"). 3. __ipv6_ifa_notify(): Calls ip6_del_rt() which specifically checks for fib6_null_entry and returns an error. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] [...] Call Trace: <TASK> __kasan_check_byte (mm/kasan/common.c:573) lock_acquire.part.0 (kernel/locking/lockdep.c:5842 (discriminator 1)) _raw_spin_lock_bh (kernel/locking/spinlock.c:182 (discriminator 1)) cleanup_prefix_route (net/ipv6/addrconf.c:1280) ipv6_del_addr (net/ipv6/addrconf.c:1342) inet6_addr_del.isra.0 (net/ipv6/addrconf.c:3119) inet6_rtm_deladdr (net/ipv6/addrconf.c:4812) rtnetlink_rcv_msg (net/core/rtnetlink.c:6997) netlink_rcv_skb (net/netlink/af_netlink.c:2555) netlink_unicast (net/netlink/af_netlink.c:1344) netlink_sendmsg (net/netlink/af_netlink.c:1899) __sock_sendmsg (net/socket.c:802 (discriminator 4)) ____sys_sendmsg (net/socket.c:2698) ___sys_sendmsg (net/socket.c:2752) __sys_sendmsg (net/socket.c:2784) do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) Fixes: 5eb902b ("net/ipv6: Remove expired routes with a separated list of routes.") Reported-by: Ji'an Zhou <eilaimemedsnaimel@gmail.com> Reviewed-by: David Ahern <dahern@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/20260609145448.768318-1-idosch@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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…ister NAT helpers such as nf_nat_h323 store a raw pointer to module text in exp->expectfn (e.g. ip_nat_q931_expect). nf_ct_helper_expectfn_unregister() only unlinks the callback descriptor and never walks the expectation table, so an expectation pending at module removal survives with a dangling exp->expectfn into freed module text. When the expected connection arrives, init_conntrack() invokes exp->expectfn(), now a stale pointer into the unloaded module. Reproduced on a KASAN build by loading the H.323 helpers, creating a Q.931 expectation, unloading nf_nat_h323, then connecting to the expected port: Oops: int3: 0000 [#1] SMP KASAN NOPTI RIP: 0010:0xffffffffa06102d1 init_conntrack.isra.0 (net/netfilter/nf_conntrack_core.c:1862) nf_conntrack_in (net/netfilter/nf_conntrack_core.c:2049) ipv4_conntrack_local (net/netfilter/nf_conntrack_proto.c:223) nf_hook_slow (net/netfilter/core.c:619) __ip_local_out (net/ipv4/ip_output.c:120) __tcp_transmit_skb (net/ipv4/tcp_output.c:1715) tcp_connect (net/ipv4/tcp_output.c:4374) tcp_v4_connect (net/ipv4/tcp_ipv4.c:345) __sys_connect (net/socket.c:2167) Modules linked in: nf_conntrack_h323 [last unloaded: nf_nat_h323] Reaching the dangling state requires CAP_SYS_MODULE in the initial user namespace to remove a NAT helper that still has live expectations, so this is a robustness fix; leaving an expectation pointing at freed text is wrong regardless. Add nf_ct_helper_expectfn_destroy(), which walks the expectation table and drops every expectation whose ->expectfn matches the descriptor being torn down. Call it from each NAT helper's exit path after the existing RCU grace period, so no expectation outlives the code it points at and no extra synchronize_rcu() is introduced. With the fix, the same reproducer runs to completion without the Oops. Fixes: f587de0 ("[NETFILTER]: nf_conntrack/nf_nat: add H.323 helper port") Reported-by: Xiang Mei <xmei5@asu.edu> Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Jun 29, 2026
The xe driver keeps track of whether to probe display, and whether display hardware is there, using xe->info.probe_display. It gets set to false if there's no display after intel_display_device_probe(). However, the display may also be disabled via fuses, detected at a later time in intel_display_device_info_runtime_init(). In this case, the xe driver does for_each_intel_crtc() on uninitialized mode config in xe_display_flush_cleanup_work(), leading to a NULL pointer dereference, and generally calls display code with display info cleared. Check for intel_display_device_present() after intel_display_device_info_runtime_init(), and reset xe->info.probe_display as necessary. Also do unset_display_features() for completeness, although display runtime init has already done that. This will need to be unified across all cases later. Move intel_display_device_info_runtime_init() call slightly earlier, similar to i915, to avoid a bunch of unnecessary setup for no display cases. Note #1: The xe driver has no business doing low level display plumbing like for_each_intel_crtc() to begin with. It all needs to happen in display code. Note qualcomm-linux#2: The actual bug is present already in commit 44e6949 ("drm/xe/display: Implement display support"), but the oops was likely introduced later at commit ddf6492 ("drm/xe/display: Make display suspend/resume work on discrete"). Fixes: 44e6949 ("drm/xe/display: Implement display support") Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/7904 Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/6150 Cc: stable@vger.kernel.org # v6.8+ Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com> Link: https://patch.msgid.link/20260515160920.1082842-1-jani.nikula@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com> (cherry picked from commit 7c3eb9f) Signed-off-by: Matthew Brost <matthew.brost@intel.com>
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Debug patch to trakc the reads and writes from arm-smmu's s2cr implementation.