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

[Kevin Wolf <kwolf@redhat.com>]

Am 25.07.2022 um 09:38 hat Emanuele Giuseppe Esposito geschrieben:
> 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).
> 
> 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;
>  }

Ah, so this patch does what I asked for in an earlier patch. I wonder if
it should be squashed there.

Vladimir's finding that we have an access in mirror may need a fix, but
while incomplete, this patch isn't wrong:

Reviewed-by: Kevin Wolf <kwolf@redhat.com>