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Date:   Fri, 9 Jun 2023 12:31:04 -0700
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To:     Linus Torvalds <torvalds@linux-foundation.org>
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From:   Guenter Roeck <linux@roeck-us.net>
Subject: Re: [PATCH 5.15 000/159] 5.15.116-rc1 review
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On 6/9/23 12:06, Linus Torvalds wrote:
> On Fri, Jun 9, 2023 at 11:42 AM Guenter Roeck <linux@roeck-us.net> wrote:
>>
>> I managed to revise my bisect script sufficiently enough to get reliable
>> results. It looks like the culprit is commit 503e554782c9 (" debugobject:
>> Ensure pool refill (again)"); see bisect log below. Bisect on four
>> different systems all have the same result. After reverting this patch,
>> I do not see the problem anymore (again, confirmed on four different
>> systems).
> 
> Does this happen on mainline too? It's commit 0af462f19e63 in the upstream tree.
> 
> It was in 6.4-rc1, and I see a clean result from you at least for
> -rc2, so for some reason it sounds like upstream is ok. But I don't
> really see why that would be the case...
> 

I see the problem only in v5.15.y, to the point where it is almost
impossible to get a clean test of all arm-v7 systems. Affected are
npcm (Nuvoton) boards (kudo-bmc, quanta-gsj, npcm750-evb) as well as
orangepi-pc. I don't see it in any other branch or with any other
platform/architecture.

Mainline is fine; I have not seen any problems since -rc2.

I have no idea what is going on either, only that I can reliably
reproduce the problem (and of course it disappears if CONFIG_DEBUG_OBJECTS
is disabled).

Guenter