From mboxrd@z Thu Jan  1 00:00:00 1970
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 <87y23s3byb.fsf@xenomai.org>
From: Philippe Gerum <rpm@xenomai.org>
Subject: Re: mm problems with 5.15.9-dovetail1
Date: Sat, 08 Jan 2022 16:21:24 +0100
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To: Jan Kiszka <jan.kiszka@siemens.com>
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Philippe Gerum <rpm@xenomai.org> writes:

> Hi,
>
> Jan Kiszka <jan.kiszka@siemens.com> writes:
>
>> Hi Philippe,
>>
>> seems we have some issue with the new 5.15 dovetail kernel, see e.g.
>>
>> https://source.denx.de/Xenomai/xenomai-images/-/jobs/371693
>> https://source.denx.de/Xenomai/xenomai-images/-/jobs/371694
>> https://source.denx.de/Xenomai/xenomai-images/-/jobs/371695
>> (kernel BUG at mm/rmap.c:1049!)
>>
>> Or are there changes needed on Xenomai side?
>
> Nope. Plain bug I'd say. I'll have look at this in a couple of days.

posix_fork is triggering the bug. The logic disabling COW for dovetailed
tasks breaks with Cobalt over 5.15, but does not with EVL which explains
why I did not notice earlier. Working on this.

-- 
Philippe.