Re: the stuttering regression in 7.0: should I have done something different

[John Paul Adrian Glaubitz]

Hi Thomas,

On Fri, 2026-05-15 at 17:35 +0200, Thomas Gleixner wrote:
> > Thank you again for the debugging guidance and for the feedback on my 
> > original patch addressing the timer starvation issue. It was a pleasure 
> > contributing to the resolution.
> 
> Thank you for going through the hassle of chasing it down and providing
> the debug data to analyze it.
> 
> I'm still puzzled how this went unnoticed for almost two decades:
> 
>    112f48716d9f ("[SPARC64]: Add clocksource/clockevents support.")

My suspicion is that it was previously visible only in certain edge cases,
in particular on machines with many cores and high load.

Case in point: In the past, SPARC LDOMs with lots of virtual CPUs could
crash in rares cases when building packages such as GCC or LLVM and running
their testsuites.

I don't know if Tony's patch fixes this long-time issue that we have observed
in the past on Debian's buildds, but I think that the chances aren't too bad.

Tony, please clean up your patch and add an elaborate explanation in the commit
message! Hope to see this fix landed as soon as possible!

Thanks to both of you for hunting this down!

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
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