Re: [PATCH] ftrace/x86: fix x86-32 triple fault with graph tracing and suspend-to-ram

From: Rafael J. Wysocki
Date: Tue Mar 28 2017 - 17:53:41 EST


On Tuesday, March 28, 2017 04:42:18 PM Josh Poimboeuf wrote:
> On Tue, Mar 28, 2017 at 11:12:42PM +0200, Rafael J. Wysocki wrote:
> > On Tuesday, March 28, 2017 10:55:46 AM Josh Poimboeuf wrote:
> > > On Tue, Mar 28, 2017 at 11:39:41AM -0400, Steven Rostedt wrote:
> > > > On Tue, 28 Mar 2017 11:51:45 +0200
> > > > Paul Menzel <pmenzel@xxxxxxxxxxxxx> wrote:
> > > >
> > > > > With both patches applied `./analyze_suspend.py -config
> > > > > suspend-callgraph.cfg -filter i915` succeeds on a Lenovo X60t, so
> > > > > suspend and resume work perfectly, when tracing is enabled.
> > > > >
> > > > > Tested-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
> > > > >
> > > > > Itâd be awesome, if you could tag both patches for inclusion into the
> > > > > stable Linux Kernel series.
> > > >
> > > > As long as they are not dependent on my patch series, I'm fine with
> > > > these going to stable.
> > >
> > > Stable sounds fine to me too. Both patches are independent of your
> > > x86-32 fentry patch set.
> >
> > Does https://patchwork.kernel.org/patch/9628301/ need to go into any particular
> > -stable series or just all of them?
> >
> > Or should a Fixes: tag be added to it?
>
> As far as I can tell this issue has been around since the function_graph
> tracer was introduced in 2008:
>
> 15e6cb3673ea ("tracing: add a tracer to catch execution time of kernel functions")
>
> (Though only for gcc >= 4.4.)
>
> Not sure if it's overkill to specify 'Fixes' for an 8+ year old bug? I
> guess it can't hurt anything.
>
> I think it can go in all of the stable branches.

OK, thanks!