Re: [PATCH] scsi: libiscsi: fix shifting of DID_REQUEUE host byte

[Steffen Maier]

Use wrapper functions to advertize their use in an attempt to avoid 
wrong shifting in the future?

On 10/09/2017 01:33 PM, Johannes Thumshirn wrote:
> The SCSI host byte should be shifted left by 16 in order to have
> scsi_decide_disposition() do the right thing (.i.e. requeue the command).
>
> Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
> Fixes: 661134ad3765 ("[SCSI] libiscsi, bnx2i: make bound ep check common")
> Cc: Lee Duncan <lduncan@xxxxxxxx>
> Cc: Hannes Reinecke <hare@xxxxxxx>
> Cc: Bart Van Assche <Bart.VanAssche@xxxxxxxxxxx>
> Cc: Chris Leech <cleech@xxxxxxxxxx>
> ---
>   drivers/scsi/libiscsi.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
> index bd4605a34f54..9cba4913b43c 100644
> --- a/drivers/scsi/libiscsi.c
> +++ b/drivers/scsi/libiscsi.c
> @@ -1728,7 +1728,7 @@ int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
>
>   	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
>   		reason = FAILURE_SESSION_IN_RECOVERY;
> -		sc->result = DID_REQUEUE;
> +		sc->result = DID_REQUEUE << 16;

not sure if this really wants to reset the other parts of result, but if 
so (and they are not 0 already anyway), preceed the set_host_byte() by:
		sc->result = 0;

		set_host_byte(sc, DID_REQUEUE);

>   		goto fault;
>   	}

--
Mit freundlichen GrÃÃen / Kind regards
Steffen Maier

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