Re: XFS metadata CRC errors on zram block device on ppc64le architecture

[Linux regression tracking #adding (Thorsten Leemhuis)]

[CCing the regression list, as it should be in the loop for regressions:
https://docs.kernel.org/admin-guide/reporting-regressions.html]

[TLDR: 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.
See link in footer if these mails annoy you.]

On 02.08.23 05:31, Dusty Mabe wrote:
> In Fedora CoreOS we found an issue with an interaction of an XFS filesystem on a zram block device on ppc64le:
> 
> - https://github.com/coreos/fedora-coreos-tracker/issues/1489
> - https://bugzilla.redhat.com/show_bug.cgi?id=2221314
> 
> The dmesg output shows several errors:
> 
> ```
> [ 3247.206007] XFS (zram0): Mounting V5 Filesystem 0b7d6149-614c-4f4c-9a1f-a80a9810f58f
> [ 3247.210781] XFS (zram0): Metadata CRC error detected at xfs_agf_read_verify+0x108/0x150 [xfs], xfs_agf block 0x80008 
> [ 3247.211121] XFS (zram0): Unmount and run xfs_repair
> [...]
> We ran a kernel bisect and narrowed it down to offending commit af8b04c6:
> 
> ```
> [root@ibm-p8-kvm-03-guest-02 linux]# git bisect good
> af8b04c63708fa730c0257084fab91fb2a9cecc4 is the first bad commit
> commit af8b04c63708fa730c0257084fab91fb2a9cecc4
> Author: Christoph Hellwig <hch@xxxxxx>
> Date:   Tue Apr 11 19:14:46 2023 +0200
> 
>     zram: simplify bvec iteration in __zram_make_request
>     
> [...]

Thanks for the report. To be sure the issue doesn't fall through the
cracks unnoticed, I'm adding it to regzbot, the Linux kernel regression
tracking bot:

#regzbot ^introduced af8b04c63708fa730c0257084fab91fb2a9cec
#regzbot title zram: XFS metadata CRC errors on zram block device on ppc64le
#regzbot ignore-activity

This isn't a regression? This issue or a fix for it are already
discussed somewhere else? It was fixed already? You want to clarify when
the regression started to happen? Or point out I got the title or
something else totally wrong? Then just reply and tell me -- ideally
while also telling regzbot about it, as explained by the page listed in
the footer of this mail.

Developers: When fixing the issue, remember to add 'Link:' tags pointing
to the report (the parent of this mail). See page linked in footer for
details.

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
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