Re: [PATCH] uprobes: wait for mmap_sem for write killable

From: Oleg Nesterov
Date: Mon Feb 29 2016 - 13:39:07 EST


On 02/29, Michal Hocko wrote:
>
> On Mon 29-02-16 19:11:06, Oleg Nesterov wrote:
> > On 02/29, Michal Hocko wrote:
> > >
> > > --- a/kernel/events/uprobes.c
> > > +++ b/kernel/events/uprobes.c
> > > @@ -1130,7 +1130,9 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)
> > > struct vm_area_struct *vma;
> > > int ret;
> > >
> > > - down_write(&mm->mmap_sem);
> > > + if (down_write_killable(&mm->mmap_sem))
> > > + return -EINTR;
> > > +
> > > if (mm->uprobes_state.xol_area) {
> > > ret = -EALREADY;
> > > goto fail;
> > > @@ -1468,7 +1470,8 @@ static void dup_xol_work(struct callback_head *work)
> > > if (current->flags & PF_EXITING)
> > > return;
> > >
> > > - if (!__create_xol_area(current->utask->dup_xol_addr))
> > > + if (!__create_xol_area(current->utask->dup_xol_addr) &&
> > > + !fatal_signal_pending(current)
> > > uprobe_warn(current, "dup xol area");
> > > }
> >
> > Looks good, thanks.
>
> Can I consider this your Acked-by?

Yes, feel free to add. I forgot to add it.

Oleg.