lkml.org 
[lkml]   [2014]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: frequent lockups in 3.18rc4
On Thu, Nov 20, 2014 at 3:39 PM, Tejun Heo <tj@kernel.org> wrote:
> On Thu, Nov 20, 2014 at 03:08:03PM -0800, Andy Lutomirski wrote:
>> > So, for now, all we need is adding nmi check in percpu accessors,
>> > right?
>> >
>>
>> What's the issue with nmi? Page faults are supposed to nest correctly
>> inside nmi, right?
>
> Thought they couldn't. Looking at the trace that Frederic linked, it
> looks like straight-out tracing function recursion due to an
> unexpected fault while holding a lock. I don't think this can be
> annotated from percpu accessor side. There's nothing special about
> the context. :(

That doesn't appear to have anything to with nmi though, right?

Wouldn't this issue be fixed by moving the vmalloc_fault check into
do_page_fault before exception_enter?

--Andy


\
 
 \ /
  Last update: 2014-11-21 01:21    [W:0.708 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site