Subject: Re: linux-next: manual merge of the ext3 tree with the mm-stable tree

From: Stephen Rothwell <[email-masked]>
Date: Mon, 23 Sep 2024 08:33:14 +1000

Hi all,

On Fri, 6 Sep 2024 11:19:00 +1000 Stephen Rothwell <[email-masked]> wrote:
>
> Today's linux-next merge of the fs-next tree got a conflict in:
> 
>   mm/filemap.c
> 
> between commit:
> 
>   0a2d82946be6 ("mm: allow read-ahead with IOCB_NOWAIT set")
> 
> from the mm-stable tree and commit:
> 
>   d23805138ac0 ("fsnotify: generate pre-content permission event on page fault")
> 
> from the ext3 tree.
> 
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
> 
> diff --cc mm/filemap.c
> index 4fdd2e49f9dc,b722ce0ca6c5..000000000000
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@@ -46,7 -46,7 +46,8 @@@
>   #include <linux/pipe_fs_i.h>
>   #include <linux/splice.h>
>   #include <linux/rcupdate_wait.h>
>  +#include <linux/sched/mm.h>
> + #include <linux/fsnotify.h>
>   #include <asm/pgalloc.h>
>   #include <asm/tlbflush.h>
>   #include "internal.h"
> @@@ -3303,8 -3391,17 +3407,19 @@@ vm_fault_t filemap_fault(struct vm_faul
>   	if (unlikely(index >= max_idx))
>   		return VM_FAULT_SIGBUS;
>   
>  +	trace_mm_filemap_fault(mapping, index);
>  +
> + 	/*
> + 	 * If we have pre-content watchers then we need to generate events on
> + 	 * page fault so that we can populate any data before the fault.
> + 	 */
> + 	ret = __filemap_fsnotify_fault(vmf, &fpin);
> + 	if (unlikely(ret)) {
> + 		if (fpin)
> + 			fput(fpin);
> + 		return ret;
> + 	}
> + 
>   	/*
>   	 * Do we have something in the page cache already?
>   	 */

This is now a conflict between the ext3 tree Linus' tree.

-- 
Cheers,
Stephen Rothwell