The patch titled
Subject: fork: silence a false postive warning in __mmdrop
has been added to the -mm tree. Its filename is
fork-silence-a-false-postive-warning-in-__mmdrop.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/fork-silence-a-false-postive-warning-in-__mmdrop.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/fork-silence-a-false-postive-warning-in-__mmdrop.patch
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The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Qian Cai <cai@xxxxxx>
Subject: fork: silence a false postive warning in __mmdrop
commit bf2c59fce407 ("sched/core: Fix illegal RCU from offline CPUs")
delayed,
idle->active_mm = &init_mm;
into finish_cpu() instead of idle_task_exit() which results in a false
positive warning that was originally designed in the commit 3eda69c92d47
("kernel/fork.c: detect early free of a live mm").
WARNING: CPU: 127 PID: 72976 at kernel/fork.c:697
__mmdrop+0x230/0x2c0
do_exit+0x424/0xfa0
Call Trace:
do_exit+0x424/0xfa0
do_group_exit+0x64/0xd0
sys_exit_group+0x24/0x30
system_call_exception+0x108/0x1d0
system_call_common+0xf0/0x278
Link: http://lkml.kernel.org/r/20200604150344.1796-1-cai@xxxxxx
Fixes: bf2c59fce407 ("sched/core: Fix illegal RCU from offline CPUs")
Signed-off-by: Qian Cai <cai@xxxxxx>
Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc)
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/fork.c | 1 -
1 file changed, 1 deletion(-)
--- a/kernel/fork.c~fork-silence-a-false-postive-warning-in-__mmdrop
+++ a/kernel/fork.c
@@ -694,7 +694,6 @@ void __mmdrop(struct mm_struct *mm)
{
BUG_ON(mm == &init_mm);
WARN_ON_ONCE(mm == current->mm);
- WARN_ON_ONCE(mm == current->active_mm);
mm_free_pgd(mm);
destroy_context(mm);
mmu_notifier_subscriptions_destroy(mm);
_
Patches currently in -mm which might be from cai@xxxxxx are
fork-silence-a-false-postive-warning-in-__mmdrop.patch
mm-page_alloc-silence-a-kasan-false-positive.patch
mm-kmemleak-silence-kcsan-splats-in-checksum.patch
mm-frontswap-mark-various-intentional-data-races.patch
mm-page_io-mark-various-intentional-data-races.patch
mm-page_io-mark-various-intentional-data-races-v2.patch
mm-swap_state-mark-various-intentional-data-races.patch
mm-swapfile-fix-and-annotate-various-data-races.patch
mm-swapfile-fix-and-annotate-various-data-races-v2.patch
mm-page_counter-fix-various-data-races-at-memsw.patch
mm-memcontrol-fix-a-data-race-in-scan-count.patch
mm-list_lru-fix-a-data-race-in-list_lru_count_one.patch
mm-mempool-fix-a-data-race-in-mempool_free.patch
mm-rmap-annotate-a-data-race-at-tlb_flush_batched.patch
mm-swap-annotate-data-races-for-lru_rotate_pvecs.patch
mm-annotate-a-data-race-in-page_zonenum.patch
