Re: [PATCH RESEND 2/2] btrfs:Fix error handling in the function btrfs_dev_replace_kthread

[Chris Mason <clm@fb.com>]

On Tue, Dec 29, 2015 at 08:10:07PM -0500, Nicholas Krause wrote:
> This fixes error handling in the function btrfs_dev_replace_kthread
> by checking if the call to the function btrfs_dev_replace_continue_on_mount
> has failed and if so return the error code to this function's caller in
> order to signal a failure has occurred when calling this particular
> function.
> 
> Signed-off-by: Nicholas Krause <xerofoify@gmail.com>
> ---
>  fs/btrfs/dev-replace.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
> index 38ffd73..b26f68c 100644
> --- a/fs/btrfs/dev-replace.c
> +++ b/fs/btrfs/dev-replace.c
> @@ -803,6 +803,7 @@ static int btrfs_dev_replace_kthread(void *data)
>  	struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
>  	struct btrfs_ioctl_dev_replace_args *status_args;
>  	u64 progress;
> +	int ret;
>  
>  	status_args = kzalloc(sizeof(*status_args), GFP_NOFS);
>  	if (status_args) {
> @@ -820,7 +821,9 @@ static int btrfs_dev_replace_kthread(void *data)
>  			"<missing target disk>",
>  			(unsigned int)progress);
>  	}
> -	btrfs_dev_replace_continue_on_mount(fs_info);
> +	ret = btrfs_dev_replace_continue_on_mount(fs_info);
> +	if (ret)
> +		return ret;
>  	atomic_set(&fs_info->mutually_exclusive_operation_running, 0);

This atomic_set that you're skipping is really important.

-chris