Re: [PATCH v2] modules: Only return -EEXIST for modules that have finished loading

From: Heiko Carstens
Date: Wed May 08 2019 - 06:57:36 EST

Hi Prarit,

On Tue, May 07, 2019 at 10:54:13AM -0400, Prarit Bhargava wrote:
> Heiko, it would still be good to get a test of this patch from you. I
> tested this here at Red Hat on some System Z machines. Without the
> modification made here in v2, the systems failed to boot ~10% of the time.
> After the modification I do not see any boot failures. I also was
> able to reproduce the boot issue with the acpi_cpufreq driver on a very
> large & fast x86 system which had closer to 100% failure rate without
> the changes in v2. After the modification in v2 the system has rebooted
> all weekend without any issues.

I gave it a try on a machine that failed quite reliably with your
first patch (the one that was in linux-next and caused problems on
s390) - it now comes up without any issues. Also a machine with 80
CPUs (+SMT2 -> 160 CPUs) comes up without problems.

So everything seems to work. Thanks!