On Fri 05-05-23 21:24:29, Baokun Li wrote:
> When ext4_iomap_overwrite_begin() calls ext4_iomap_begin() map blocks may
> fail for some reason (e.g. memory allocation failure, bare disk write), and
> later because "iomap->type ! = IOMAP_MAPPED" triggers WARN_ON(). When ext4
> iomap_begin() returns an error, it is normal that the type of iomap->type
> may not match the expectation. Therefore, we only determine if iomap->type
> is as expected when ext4_iomap_begin() is executed successfully.
>
> Reported-by: [email protected]
> Link: https://lore.kernel.org/all/[email protected]
> Signed-off-by: Baokun Li <[email protected]>
Makes sense. Feel free to add:
Reviewed-by: Jan Kara <[email protected]>
Honza
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 0d5ba922e411..19c884abe52b 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -3375,7 +3375,7 @@ static int ext4_iomap_overwrite_begin(struct inode *inode, loff_t offset,
> */
> flags &= ~IOMAP_WRITE;
> ret = ext4_iomap_begin(inode, offset, length, flags, iomap, srcmap);
> - WARN_ON_ONCE(iomap->type != IOMAP_MAPPED);
> + WARN_ON_ONCE(!ret && iomap->type != IOMAP_MAPPED);
> return ret;
> }
>
> --
> 2.31.1
>
--
Jan Kara <[email protected]>
SUSE Labs, CR