On Fri, Dec 08, 2023 at 02:39:36PM -0800, Luis Chamberlain wrote:
> Commit aa5b9178c0190 ("mm: invalidation check mapping before folio_contains")
> added on v6.6-rc1 moved the VM_BUG_ON_FOLIO() on invalidate_inode_pages2_range()
> after the truncation check.
> 
> We managed to hit this VM_BUG_ON_FOLIO() a few times on v6.6-rc5 with a slew
> of fstsets tests on kdevops [0] on the following XFS config as defined by
> kdevops XFS's configurations [1] for XFS with the following failure rates
> annotated:
> 
>   * xfs_reflink_4k: F:1/278 - one out of 278 times
>     - generic/451: (trace pasted below after running test over 17 hours)
>   * xfs_nocrc_4k: F:1/1604 - one ou tof 1604 times
>      - generic/451: https://gist.github.com/mcgrof/2c40a14979ceeb7321d2234a525c32a6
> 
> To be clear F:1/1604 means you can run the test in a loop and on test number
> about 1604 you may run into the bug. It would seem Zorro had hit also
> with a 64k directory size (mkfs.xfs -n size=65536) on v5.19-rc2, so prior 
> to Hugh's move of the VM_BUG_ON_FOLIO() while testing generic/132 [0].
> 
> My hope is that this could help those interested in reproducing, to
> spawn up kdevops and just run the test in a loop in the same way.
> Likewise, if you have a fix to test we can test it as well, but it will
> take a while as we want to run the test in a loop over and over many
> times.

I'm pretty sure this is the same problem recently diagnosed by Charan.
It's terribly rare, so it'll take a while to find out.  Try the attached
patch?