[regression] linux-6.6.y, minmax: virtual memory exhausted in i586 chroot during kernel compilation

From: Linux regression tracking (Thorsten Leemhuis)
Date: Mon Feb 12 2024 - 11:17:09 EST


Hi Greg, Sasha, and David,

I noticed a regression report in bugzilla.kernel.org that seems to be
specific to the linux-6.6.y series:

Quoting from https://bugzilla.kernel.org/show_bug.cgi?id=218484 :

> After upgrading to version 6.6.16, the kernel compilation on a i586
> arch (on a 32bit chroot in a 64bit host) fails with a message:
>
> virtual memory exhausted: Cannot allocate memory
>
> this happens even lowering the number of parallel compilation
> threads. On a x86_64 arch the same problem doesn't occur. It's not
> clear whether some weird recursion is triggered that exhausts the
> memory, but it seems that the problem is caused by the patchset
> 'minmax' added to the 6.6.16 version, in particular it seems caused
> by these patches:
>
> - minmax-allow-min-max-clamp-if-the-arguments-have-the-same-signedness.patch
> - minmax-fix-indentation-of-__cmp_once-and-__clamp_once.patch
> - minmax-allow-comparisons-of-int-against-unsigned-char-short.patch
> - minmax-relax-check-to-allow-comparison-between-unsigned-arguments-and-signed-constants.patch
>
> Reverting those patches fixes the memory exhaustion problem during compilation.

The reporter later added:

> From a quick test the same problem doesn't occur in 6.8-rc4.
See the ticket for more details.

Note, you have to use bugzilla to reach the reporter, as I sadly[1] can
not CCed them in mails like this.

[TLDR for the rest of this mail: I'm adding this report to the list of
tracked Linux kernel regressions; the text you find below is based on a
few templates paragraphs you might have encountered already in similar
form.]

BTW, let me use this mail to also add the report to the list of tracked
regressions to ensure it's doesn't fall through the cracks:

#regzbot introduced: 204c653d5d0c79940..9487d93f172acef
https://bugzilla.kernel.org/show_bug.cgi?id=218484
#regzbot title: minmax: virtual memory exhausted in 6.6.16 with i586 chroot
#regzbot ignore-activity

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
Everything you wanna know about Linux kernel regression tracking:
https://linux-regtracking.leemhuis.info/about/#tldr
If I did something stupid, please tell me, as explained on that page.

[1] because bugzilla.kernel.org tells users upon registration their
"email address will never be displayed to logged out users"