SENSE_CODE(LUN_COMM_FAILURE) has an ABORTED COMMAND sense key,
so it results in a retry in Linux.  To ensure that EREMOTEIO
is forwarded to the guest, use a HARDWARE ERROR sense key
instead.  Note that the code before commit d7a84021d was incorrect
because it used HARDWARE_ERROR as a SCSI status, not as a sense
key.

Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 scsi/utils.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scsi/utils.c b/scsi/utils.c
index 873e05aeaf..357b036671 100644
--- a/scsi/utils.c
+++ b/scsi/utils.c
@@ -589,7 +589,7 @@ int scsi_sense_from_errno(int errno_value, SCSISense *sense)
         return TASK_SET_FULL;
 #ifdef CONFIG_LINUX
         /* These errno mapping are specific to Linux.  For more information:
-         * - scsi_decide_disposition in drivers/scsi/scsi_error.c
+         * - scsi_check_sense and scsi_decide_disposition in drivers/scsi/scsi_error.c
          * - scsi_result_to_blk_status in drivers/scsi/scsi_lib.c
          * - blk_errors[] in block/blk-core.c
          */
@@ -599,7 +599,7 @@ int scsi_sense_from_errno(int errno_value, SCSISense *sense)
         *sense = SENSE_CODE(READ_ERROR);
         return CHECK_CONDITION;
     case EREMOTEIO:
-        *sense = SENSE_CODE(LUN_COMM_FAILURE);
+        *sense = SENSE_CODE(TARGET_FAILURE);
         return CHECK_CONDITION;
 #endif
     case ENOMEDIUM:
-- 
2.29.2

On 3/9/21 2:57 PM, Paolo Bonzini wrote:
> SENSE_CODE(LUN_COMM_FAILURE) has an ABORTED COMMAND sense key,
> so it results in a retry in Linux.  To ensure that EREMOTEIO
> is forwarded to the guest, use a HARDWARE ERROR sense key
> instead.  Note that the code before commit d7a84021d was incorrect
> because it used HARDWARE_ERROR as a SCSI status, not as a sense
> key.

It is not clear whether if it deserves a 'Fixes: d7a84021db8 ("scsi:
introduce scsi_sense_from_errno()")' or not...

> Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

> ---
>  scsi/utils.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/scsi/utils.c b/scsi/utils.c
> index 873e05aeaf..357b036671 100644
> --- a/scsi/utils.c
> +++ b/scsi/utils.c
> @@ -589,7 +589,7 @@ int scsi_sense_from_errno(int errno_value, SCSISense *sense)
>          return TASK_SET_FULL;
>  #ifdef CONFIG_LINUX
>          /* These errno mapping are specific to Linux.  For more information:
> -         * - scsi_decide_disposition in drivers/scsi/scsi_error.c
> +         * - scsi_check_sense and scsi_decide_disposition in drivers/scsi/scsi_error.c
>           * - scsi_result_to_blk_status in drivers/scsi/scsi_lib.c
>           * - blk_errors[] in block/blk-core.c
>           */
> @@ -599,7 +599,7 @@ int scsi_sense_from_errno(int errno_value, SCSISense *sense)
>          *sense = SENSE_CODE(READ_ERROR);
>          return CHECK_CONDITION;
>      case EREMOTEIO:
> -        *sense = SENSE_CODE(LUN_COMM_FAILURE);
> +        *sense = SENSE_CODE(TARGET_FAILURE);
>          return CHECK_CONDITION;
>  #endif
>      case ENOMEDIUM:
> 

On 09/03/21 15:14, Philippe Mathieu-Daudé wrote:
>> SENSE_CODE(LUN_COMM_FAILURE) has an ABORTED COMMAND sense key,
>> so it results in a retry in Linux.  To ensure that EREMOTEIO
>> is forwarded to the guest, use a HARDWARE ERROR sense key
>> instead.  Note that the code before commit d7a84021d was incorrect
>> because it used HARDWARE_ERROR as a SCSI status, not as a sense
>> key.
> 
> It is not clear whether if it deserves a 'Fixes: d7a84021db8 ("scsi:
> introduce scsi_sense_from_errno()")' or not...

Yes, why not.  That was in turn a bugfix but not the best.

Paolo

>> Reported-by: Marc-André Lureau<marcandre.lureau@redhat.com>
>> Signed-off-by: Paolo Bonzini<pbonzini@redhat.com>
> Reviewed-by: Philippe Mathieu-Daudé<philmd@redhat.com>
>