Re: mm: mkfs.ext4 invoked oom-killer on i386 - pagecache_get_page

[Naresh Kamboju]

On Wed, 20 May 2020 at 17:26, Naresh Kamboju <naresh.kamboju@xxxxxxxxxx> wrote:
>
>
> This issue is specific on 32-bit architectures i386 and arm on linux-next tree.
> As per the test results history this problem started happening from
> Bad : next-20200430
> Good : next-20200429
>
> steps to reproduce:
> dd if=/dev/disk/by-id/ata-SanDisk_SSD_PLUS_120GB_190504A00573
> of=/dev/null bs=1M count=2048
> or
> mkfs -t ext4 /dev/disk/by-id/ata-SanDisk_SSD_PLUS_120GB_190804A00BE5
>
>
> Problem:
> [   38.802375] dd invoked oom-killer: gfp_mask=0x100cc0(GFP_USER),
> order=0, oom_score_adj=0

As a part of investigation on this issue LKFT teammate Anders Roxell
git bisected the problem and found bad commit(s) which caused this problem.

The following two patches have been reverted on next-20200519 and retested the
reproducible steps and confirmed the test case mkfs -t ext4 got PASS.
( invoked oom-killer is gone now)

Revert "mm, memcg: avoid stale protection values when cgroup is above
protection"
    This reverts commit 23a53e1c02006120f89383270d46cbd040a70bc6.

Revert "mm, memcg: decouple e{low,min} state mutations from protection
checks"
    This reverts commit 7b88906ab7399b58bb088c28befe50bcce076d82.

i386 test log shows mkfs -t ext4 pass
https://lkft.validation.linaro.org/scheduler/job/1443405#L1200

ref:
https://lore.kernel.org/linux-mm/cover.1588092152.git.chris@xxxxxxxxxxxxxx/
https://lore.kernel.org/linux-mm/CA+G9fYvzLm7n1BE7AJXd8_49fOgPgWWTiQ7sXkVre_zoERjQKg@xxxxxxxxxxxxxx/T/#t

-- 
Linaro LKFT
https://lkft.linaro.org