Re: [PATCH] mm, proc: make clear_refs killable

From: Oleg Nesterov
Date: Mon Feb 29 2016 - 13:16:31 EST


On 02/29, Michal Hocko wrote:
>
> --- a/fs/proc/task_mmu.c
> +++ b/fs/proc/task_mmu.c
> @@ -1027,11 +1027,15 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
> };
>
> if (type == CLEAR_REFS_MM_HIWATER_RSS) {
> + if (down_write_killable(&mm->mmap_sem)) {
> + count = -EINTR;
> + goto out_mm;
> + }
> +

We do not even need to change count, userspace won't see it anyway. But I agree
it look more clean this way.

I believe the patch is fine.

Oleg.