Messages in this thread | | | Date | Wed, 8 Apr 2020 19:27:23 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH] mm/gup: Let __get_user_pages_locked() return -EINTR for fatal signal |
| |
On Wed, Apr 08, 2020 at 11:59:24AM -0400, Peter Xu wrote: > From: Hillf Danton <hdanton@sina.com> > > __get_user_pages_locked() will return 0 instead of -EINTR after commit > 4426e945df588 which added extra code to allow gup detect fatal signal > faster. Restore that behavior. > > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Peter Zijlstra <peterz@infradead.org> > Fixes: 4426e945df58 ("mm/gup: allow VM_FAULT_RETRY for multiple times") > Reported-by: syzbot+3be1a33f04dc782e9fd5@syzkaller.appspotmail.com > Signed-off-by: Hillf Danton <hdanton@sina.com> > Acked-by: Michal Hocko <mhocko@suse.com> > Signed-off-by: Peter Xu <peterx@redhat.com> > --- > > PS. Patch verified with syzbot. > > Signed-off-by: Peter Xu <peterx@redhat.com> > --- > mm/gup.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/mm/gup.c b/mm/gup.c > index afce0bc47e70..6076df8e04a4 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -1326,8 +1326,11 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, > * start trying again otherwise it can loop forever. > */ > > - if (fatal_signal_pending(current)) > + if (fatal_signal_pending(current)) { > + if (!pages_done) > + pages_done = -EINTR;
Why -EINTR here and -ERESTARTSYS at the other site?
> break; > + } > > ret = down_read_killable(&mm->mmap_sem); > if (ret) { > -- > 2.24.1 >
| |