[PATCH v2 14/14] netfs: Fix DIO write retry for filesystems without a ->prepare_write()

[ChenXiaoSong]

Looks good. Feel free to add:

Reviewed-by: ChenXiaoSong <chenxiaosong at kylinos.cn>
Tested-by: ChenXiaoSong <chenxiaosong at kylinos.cn>

在 2026/6/24 19:57, David Howells 写道:
> Fix netfs_unbuffered_write() so that it doesn't re-issue a write twice when
> the filesystem doesn't have a ->prepare_write().  The bit of code that does
> the first issue should just be removed as everything it does is done again
> when the loop it's in goes back to the top.
> 
> Reported-by: syzbot+3c74b1f0c372e98efc32 at syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?extid=3c74b1f0c372e98efc32
> Tested-by: syzbot+3c74b1f0c372e98efc32 at syzkaller.appspotmail.com
> Signed-off-by: David Howells <dhowells at redhat.com>
> cc: Paulo Alcantara <pc at manguebit.org>
> cc: hongao <hongao at uniontech.com>
> cc: ChenXiaoSong <chenxiaosong at chenxiaosong.com>
> cc: netfs at lists.linux.dev
> cc: linux-fsdevel at vger.kernel.org
> ---
>   fs/netfs/direct_write.c | 6 ------
>   1 file changed, 6 deletions(-)
> 
> diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c
> index 25f8ceb15fad..1ff1789016b8 100644
> --- a/fs/netfs/direct_write.c
> +++ b/fs/netfs/direct_write.c
> @@ -190,12 +190,6 @@ static int netfs_unbuffered_write(struct netfs_io_request *wreq)
>   			stream->prepare_write(subreq);
>   			__set_bit(NETFS_SREQ_IN_PROGRESS, &subreq->flags);
>   			netfs_stat(&netfs_n_wh_retry_write_subreq);
> -		} else {
> -			struct iov_iter source;
> -
> -			netfs_reset_iter(subreq);
> -			source = subreq->io_iter;
> -			netfs_reissue_write(stream, subreq, &source);
>   		}
>   	}
>   
> 

-- 
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