From: Michal Hocko <mhocko@xxxxxxxx> Subject: prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable PR_SET_THP_DISABLE requires mmap_sem for write. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Acked-by: Alex Thorlton <athorlton@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/sys.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff -puN kernel/sys.c~prctl-make-pr_set_thp_disable-wait-for-mmap_sem-killable kernel/sys.c --- a/kernel/sys.c~prctl-make-pr_set_thp_disable-wait-for-mmap_sem-killable +++ a/kernel/sys.c @@ -2246,7 +2246,8 @@ SYSCALL_DEFINE5(prctl, int, option, unsi case PR_SET_THP_DISABLE: if (arg3 || arg4 || arg5) return -EINVAL; - down_write(&me->mm->mmap_sem); + if (down_write_killable(&me->mm->mmap_sem)) + return -EINTR; if (arg2) me->mm->def_flags |= VM_NOHUGEPAGE; else _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
