Re: [PATCH 07/18] mm, proc: make clear_refs killable
From: Oleg Nesterov <oleg@redhat.com>
Date: 2016-02-29 17:38:58
Also in:
linux-mm, lkml
From: Oleg Nesterov <oleg@redhat.com>
Date: 2016-02-29 17:38:58
Also in:
linux-mm, lkml
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)) { + put_task_struct(task); + return -EINTR; + } + /* * Writing 5 to /proc/pid/clear_refs resets the peak * resident set size to this mm's current rss value. */ - down_write(&mm->mmap_sem); reset_mm_hiwater_rss(mm); up_write(&mm->mmap_sem); goto out_mm;@@ -1043,7 +1047,10 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, if (!(vma->vm_flags & VM_SOFTDIRTY)) continue; up_read(&mm->mmap_sem); - down_write(&mm->mmap_sem); + if (down_write_killable(&mm->mmap_sem)) { + put_task_struct(task); + return -EINTR; + }
Both lack mmput() afaics. Don't you need "goto out_mm" rather then "return" ? In this case you do not need put_task_struct(). Oleg.