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;
 }
-- 
2.31.1

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>

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

Am 27/07/2022 um 17:29 schrieb 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..

block_job_error_action -> block_job_iostatus_set_err_locked -> reads
iostatus

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

Will do, thanks

Emanuele

>>
>> 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;
>>   }
> 
>