Re: Potential Linux Crash: WARNING in ext4_dirty_folio in Linux kernel v6.13-rc5

[James Bottomley]

On Thu, 2025-04-03 at 18:12 +0100, Matthew Wilcox wrote:
[...]
> Ideas still on the table:
> 
>  - Convert all filesystems to use the XFS inode management scheme.
>    Nobody is thrilled by this large amount of work.
>  - Find a simpler version of the XFS scheme to implement for other
>    filesystems.

What's wrong with a simpler fix: if we're in PF_MEMALLOC when we try to
run inode.c:evict(), send it through a workqueue?  It will require some
preallocation (say using a superblock based work entry ... or simply
reuse the destroy_work)  but it should be doable.  The analysis says
that evicting from reclaim is very rare because it's a deletion race,
so it shouldn't matter that it's firing once per inode with this
condition.

Regards,

James