Re: fs: uninterruptible hang in handle_userfault

From: Linus Torvalds
Date: Tue Mar 01 2016 - 15:28:30 EST


On Tue, Mar 1, 2016 at 11:56 AM, Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> (The above patches are entirely untested, maybe I misread the reason
> it might be hanging and it's something else going on).

Ok, I did some half-arsed testing. I didn't have a kernel with
USERFAULT enabled, but I did compile one with both patches in place
and I don't see a hang with the test program. Of course, since I
didn't test with an unpatched kernel that would show the hang in the
first place, it's entirely possible that my "no hang" result is due to
something else. And I didn't bother to test the two patches
independently either.

But at least on the face of it, those patches fix the problem. Dmitry?

Linus