On Mon 29-02-16 18:38:45, Oleg Nesterov wrote: > 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" ? Of course I need! Thanks for catching that. > In this case you do not need put_task_struct(). Why not? Both are after get_proc_task which takes a reference to the task... I will send an updated patch. Thanks! -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>