Re: [PATCH v5 2/3] scsi: scsi_error: Fix wrong statistic when print error info

[Hannes Reinecke <hare@suse.de>]

On 6/5/24 11:17, Wenchao Hao wrote:
> shost_for_each_device() would skip devices which is in progress of
> removing, so commands of these devices would be ignored in
> scsi_eh_prt_fail_stats().
> 
> Fix this issue by using shost_for_each_device_include_deleted()
> to iterate devices in scsi_eh_prt_fail_stats().
> 
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Signed-off-by: Wenchao Hao <haowenchao22@gmail.com>
> ---
>   drivers/scsi/scsi_error.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
> index 612489afe8d2..a61fd8af3b1f 100644
> --- a/drivers/scsi/scsi_error.c
> +++ b/drivers/scsi/scsi_error.c
> @@ -409,7 +409,7 @@ static inline void scsi_eh_prt_fail_stats(struct Scsi_Host *shost,
>   	int cmd_cancel = 0;
>   	int devices_failed = 0;
>   
> -	shost_for_each_device(sdev, shost) {
> +	shost_for_each_device_include_deleted(sdev, shost) {
>   		list_for_each_entry(scmd, work_q, eh_entry) {
>   			if (scmd->device == sdev) {
>   				++total_failures;

That is wrong. We should rather add a failure counter to the SCSI host, 
and have the scsi device increase it every time a failure occurs.
Then we can avoid this loop completely.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
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