A few backports #195
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A few backports #195
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[Bug #20145]
Before this commit, both copy_compare_by_id and hash_copy will create a
copy of the ST table, so the ST table created in copy_compare_by_id will
be leaked.
h = { 1 => 2 }.compare_by_identity
10.times do
1_000_000.times do
h.select { false }
end
puts `ps -o rss= -p #{$$}`
end
Before:
110736
204352
300272
395520
460704
476736
542000
604704
682624
770528
After:
15504
16048
16144
16256
16320
16320
16752
16752
16752
16752
Previously on builds with optimizations disabled, this could result in an out of bounds read. When we had all of: * built with -O0 * Leaf builtin * Primitive.mandatory_only * "no args builtin", called by vm_call_single_noarg_inline_builti * The stack is escaped to the heap via binding or a proc This is because mk_builtin_loader generated reads for all locals regardless of whether they were used and in the case we generated a mandatory_only iseq that would include more variables than were actually available. On optimized builds, the invalid accesses would be optimized away, and this also was often unnoticed as the invalid access would just hit another part of the stack unless it had been escaped to the heap. The fix here is imperfect, as this could have false positives, but since Primitive.cexpr! is only available within the cruby codebase itself that's probably fine as a proper fix would be much more challenging (the only false positives we found were in rjit.rb). Fixes [Bug #20178] Co-authored-by: Adam Hess <[email protected]>
[bug #20149]
It looks like `sched_getcpu(3)` returns a strange number on some (virtual?) environments. I decided to remove the setaffinity mechanism because the performance does not appear to degrade on a quick benchmark even if removed. [Bug #20172]
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A few backported fixes.
-O0https://bugs.ruby-lang.org/issues/20178For https://github.com/github/ruby-architecture/issues/915