Re: [PATCH HACK RFC] cpu: Prevent late-arriving interrupts from disrupting offline

["Paul E. McKenney" <paulmck@linux.ibm.com>]

On Tue, Jun 11, 2019 at 03:14:54PM +0200, Dietmar Eggemann wrote:
> On 6/8/19 6:41 PM, Paul E. McKenney wrote:
> >On Tue, Jun 04, 2019 at 03:29:32PM +0200, Dietmar Eggemann wrote:
> >>On 6/4/19 9:45 AM, Paul E. McKenney wrote:
> >>>On Mon, Jun 03, 2019 at 03:39:18PM +0200, Dietmar Eggemann wrote:
> >>>>On 6/3/19 1:44 PM, Mark Rutland wrote:
> >>>>>On Mon, Jun 03, 2019 at 10:38:48AM +0200, Peter Zijlstra wrote:
> >>>>>>On Sat, Jun 01, 2019 at 06:12:53PM -0700, Paul E. McKenney wrote:
> >>>>>>>Scheduling-clock interrupts can arrive late in the CPU-offline process,
> 
> [...]
> 
> >>>And it looks like the reason I dropped it was that I didn't get any
> >>>response from the maintainer.  I sent a message to this effect to
> >>>linux-arm-kernel@lists.infradead.org and linux@arm.linux.org.uk on May
> >>>21, 2015.
> >>>
> >>>So here it is again.  ;-)
> >>>
> >>>I have queued this locally.  Left to myself, I add the two of you on its
> >>>Cc: list and run it through my normal process.  But given the history,
> >>>I would still want either an ack from the maintainer or, better, for
> >>>the maintainer to take the patch.
> >>>
> >>>Or is there a better way for us to proceed on this?
> >>
> >>You could send this patch also to
> >>linux-arm-kernel@lists.infradead.org and cc rmk to get his opinion
> >>on the patch.
> >
> >OK, please let me know how the testing goes.  My thought is to send the
> >patch as you suggest with your Tested-by.
> 
> Tested your patch on top of v5.2-rc4* on Arm TC2 (32bit) and CPU
> hotplug stress test. W/o your patch, the test fails within seconds
> since CPUs are not coming up again. W/ your patch, the test runs for
> hours just fine.
> 
> You can add my:
> 
> Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>

Thank you!!!

> * just for the record: one additional unrelated patch (to disable
> the NOR flash) is necessary on Arm TC2:
> https://patchwork.kernel.org/patch/10968391 .

Is this progressing, or does it also need help getting to mainline?

Left to myself, I will push my patch and assume that the NOR flash patch
will make it in its own good time -- or, alternatively, that there is
someone better positioned than me to push it.

							Thanx, Paul