Re: [PATCH v10 17/21] blockjob: protect iostatus field in BlockJob struct

[Vladimir Sementsov-Ogievskiy]

On 7/25/22 10:38, Emanuele Giuseppe Esposito wrote:
> iostatus is the only field (together with .job) that needs
> protection using the job mutex.
>
> It is set in the main loop (GLOBAL_STATE functions) but read
> in I/O code (block_job_error_action).

Hmm, block_job_error_action doesn't read iostatus..

Also, iostatus is read by by mirror_run, which is not protected.

> In order to protect it, change block_job_iostatus_set_err
> to block_job_iostatus_set_err_locked(), always called under
> job lock.
>
> Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
> ---
>   blockjob.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/blockjob.c b/blockjob.c
> index 0663faee2c..448bdb5a53 100644
> --- a/blockjob.c
> +++ b/blockjob.c
> @@ -363,7 +363,8 @@ BlockJobInfo *block_job_query(BlockJob *job, Error **errp)
>       return block_job_query_locked(job, errp);
>   }
>   
> -static void block_job_iostatus_set_err(BlockJob *job, int error)
> +/* Called with job lock held */
> +static void block_job_iostatus_set_err_locked(BlockJob *job, int error)
>   {
>       if (job->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
>           job->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
> @@ -577,8 +578,8 @@ BlockErrorAction block_job_error_action(BlockJob *job, 
> BlockdevOnError on_err,
>                    */
>                   job->job.user_paused = true;
>               }
> +            block_job_iostatus_set_err_locked(job, error);
>           }
> -        block_job_iostatus_set_err(job, error);
>       }
>       return action;
>   }


--
Best regards,
Vladimir