Re: + nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix.patch added to mm-hotfixes-unstable branch

[Mike Snitzer <snitzer@kernel.org>]

Hi Andrew,

Comment and question inlined below.

On Mon, Feb 24, 2025 at 10:54:53PM -0800, Andrew Morton wrote:
> 
> The patch titled
>      Subject: nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix
> has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
>      nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix.patch
> 
> This patch will shortly appear at
>      https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix.patch
> 
> This patch will later appear in the mm-hotfixes-unstable branch at
>     git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
> 
> Before you just go and hit "reply", please:
>    a) Consider who else should be cc'ed
>    b) Prefer to cc a suitable mailing list as well
>    c) Ideally: find the original patch on the mailing list and do a
>       reply-to-all to that, adding suitable additional cc's
> 
> *** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
> 
> The -mm tree is included into linux-next via the mm-everything
> branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
> and is updated there every 2-3 working days
> 
> ------------------------------------------------------
> From: Andrew Morton <akpm@linux-foundation.org>
> Subject: nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix
> Date: Mon Feb 24 10:53:31 PM PST 2025
> 
> fix build
> 
> Cc: Anna Schumaker <anna.schumaker@oracle.com>
> Cc: Mike Snitzer <snitzer@kernel.org>
> Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
> 
>  mm/compaction.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> --- a/mm/compaction.c~nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix
> +++ a/mm/compaction.c
> @@ -3181,7 +3181,7 @@ static int kcompactd(void *p)
>  	long default_timeout = msecs_to_jiffies(HPAGE_FRAG_CHECK_INTERVAL_MSEC);
>  	long timeout = default_timeout;
>  
> -	tsk->flags |= PF_KCOMPACTD;
> +	current->flags |= PF_KCOMPACTD;
>  	set_freezable();
>  
>  	pgdat->kcompactd_max_order = 0;
> @@ -3238,7 +3238,7 @@ static int kcompactd(void *p)
>  			pgdat->proactive_compact_trigger = false;
>  	}
>  
> -	tsk->flags &= ~PF_KCOMPACTD;
> +	current->flags &= ~PF_KCOMPACTD;
>  
>  	return 0;
>  }

I wrote my patch against stable 6.12.16 and didn't think to check
latest code (sorry!).  I can easily see we need your fix given commit
54880b5a2b5e ("mm: Create/affine kcompactd to its preferred node").

Will you fold your fix before sending to Linus or should I send a
proper v3 patch rebased to latest code?

Thanks,
Mike

> _
> 
> Patches currently in -mm which might be from akpm@linux-foundation.org are
> 
> nfs-fix-nfs_release_folio-to-not-deadlock-via-kcompactd-writeback-fix.patch
> mm-vmscan-extract-calculated-pressure-balance-as-a-function-fix.patch
> mm-madvise-split-out-mmap-locking-operations-for-madvise-fix-checkpatch-fixes.patch
> mm-madvise-remove-redundant-mmap_lock-operations-from-process_madvise-fix.patch
> lib-plistc-add-shortcut-for-plist_requeue-fix.patch
>