diff options
author | Mel Gorman <mgorman@suse.de> | 2014-01-02 15:58:49 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-01-02 17:40:30 -0500 |
commit | d0319bd52e373c661f9bc0c04dec85d6f87ac517 (patch) | |
tree | 6b437b89634575b73e090ff3efe296014320b486 /mm/huge_memory.c | |
parent | 695c60830764945cf61a2cc623eb1392d137223e (diff) |
mm: remove bogus warning in copy_huge_pmd()
Sasha Levin reported the following warning being triggered
WARNING: CPU: 28 PID: 35287 at mm/huge_memory.c:887 copy_huge_pmd+0x145/ 0x3a0()
Call Trace:
copy_huge_pmd+0x145/0x3a0
copy_page_range+0x3f2/0x560
dup_mmap+0x2c9/0x3d0
dup_mm+0xad/0x150
copy_process+0xa68/0x12e0
do_fork+0x96/0x270
SyS_clone+0x16/0x20
stub_clone+0x69/0x90
This warning was introduced by "mm: numa: Avoid unnecessary disruption
of NUMA hinting during migration" for paranoia reasons but the warning
is bogus. I was thinking of parallel races between NUMA hinting faults
and forks but this warning would also be triggered by a parallel reclaim
splitting a THP during a fork. Remote the bogus warning.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/huge_memory.c')
-rw-r--r-- | mm/huge_memory.c | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 7de1bf85f683..9c0b17295ba0 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c | |||
@@ -883,9 +883,6 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm, | |||
883 | goto out_unlock; | 883 | goto out_unlock; |
884 | } | 884 | } |
885 | 885 | ||
886 | /* mmap_sem prevents this happening but warn if that changes */ | ||
887 | WARN_ON(pmd_trans_migrating(pmd)); | ||
888 | |||
889 | if (unlikely(pmd_trans_splitting(pmd))) { | 886 | if (unlikely(pmd_trans_splitting(pmd))) { |
890 | /* split huge page running from under us */ | 887 | /* split huge page running from under us */ |
891 | spin_unlock(src_ptl); | 888 | spin_unlock(src_ptl); |