Re: [stable] [PATCH 1/2] coresight: etb10: Do not call smp_processor_id from preemptible
From: Greg KH
Date: Tue Jan 28 2020 - 03:15:27 EST
On Wed, Jan 15, 2020 at 05:28:19PM +0000, Suzuki Kuruppassery Poulose wrote:
> On 15/01/2020 17:21, Greg KH wrote:
> > On Wed, Jan 15, 2020 at 04:44:29PM +0000, Suzuki Kuruppassery Poulose wrote:
> > >
> > > Hi Greg,
> > >
> > > On 15/01/2020 15:11, Greg KH wrote:
> > > > On Thu, Jan 09, 2020 at 02:36:17PM +0000, Suzuki Kuruppassery Poulose wrote:
> > > > > On 09/01/2020 14:35, Sasha Levin wrote:
> > > > > > On Wed, Jan 08, 2020 at 11:05:40AM +0000, Suzuki K Poulose wrote:
> > > > > > > [ Upstream commit 730766bae3280a25d40ea76a53dc6342e84e6513 ]
> > > > > > >
> > > > > > > During a perf session we try to allocate buffers on the "node" associated
> > > > > > > with the CPU the event is bound to. If it is not bound to a CPU, we
> > > > > > > use the current CPU node, using smp_processor_id(). However this is
> > > > > > > unsafe
> > > > > > > in a pre-emptible context and could generate the splats as below :
> > > > > > >
> > > > > > > BUG: using smp_processor_id() in preemptible [00000000] code: perf/2544
> > > > > > >
> > > > > > > Use NUMA_NO_NODE hint instead of using the current node for events
> > > > > > > not bound to CPUs.
> > > > > > >
> > > > > > > Fixes: 2997aa4063d97fdb39 ("coresight: etb10: implementing AUX API")
> > > > > > > Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > > > > > > Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> > > > > > > Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.9 to v4.19
> > > > > > > Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> > > > > > > Link: https://lore.kernel.org/r/20190620221237.3536-5-mathieu.poirier@xxxxxxxxxx
> > > > > > >
> > > > > >
> > > > > > I've queued this for 4.9-4.19. There was a simple conflict on 4.9 which
> > > > > > also had to be resolved.
> > > > > >
> > > > >
> > > > >
> > > > > Thanks Sasha !
> > > >
> > > > Note, these had to all be dropped as they broke the build :(
> > > >
> > > > So can you please send us patches that at least build? :)
> > > >
> > >
> > > Do you have a build failure log ? I did build test it before sending it
> > > over. I tried it again on 4.9, 4.14 and 4.19. I don't hit any build
> > > failures here.
> > >
> > > Please could you share the log if you have it handy ?
> >
> > It was in the stable -rc review emails, I don't have it handy, sorry.
> >
>
> I think there is a bit of confusion here. If you're referring to
>
> https://lkml.org/lkml/2020/1/11/634
>
> as the build failure report, this is precisely my series fixes.
> I sent this series to address the build break reported by Nathan.
> The original patches were picked up from the "Fixes" tag automatically
> which broke the build due to missing "event" parameter. This series
> fixes those build issues and for sure builds fine for the affected
> versions. Trust me ;-)
Ok, for some reason it looked like the "original" commits were added to
the tree, not your backports. I've queued up your backports now, that
should solve the issue.
thanks,
greg k-h