Re: [PATCH v2] scsi: storvsc: Do not flag MAINTENANCE_IN return of SRB_STATUS_DATA_OVERRUN as an error

[Ewan Milne <emilne@redhat.com>]

On Wed, Nov 27, 2024 at 1:13 PM Cathy Avery <cavery@redhat.com> wrote:
>
> This patch partially reverts
>
>         commit 812fe6420a6e789db68f18cdb25c5c89f4561334
>         Author: Michael Kelley <mikelley@microsoft.com>
>         Date:   Fri Aug 25 10:21:24 2023 -0700
>
>         scsi: storvsc: Handle additional SRB status values
>
> HyperV does not support MAINTENANCE_IN resulting in FC passthrough
> returning the SRB_STATUS_DATA_OVERRUN value. Now that SRB_STATUS_DATA_OVERRUN
> is treated as an error multipath ALUA paths go into a faulty state as multipath
> ALUA submits RTPG commands via MAINTENANCE_IN.
>
> [    3.215560] hv_storvsc 1d69d403-9692-4460-89f9-a8cbcc0f94f3:
> tag#230 cmd 0xa3 status: scsi 0x0 srb 0x12 hv 0xc0000001
> [    3.215572] scsi 1:0:0:32: alua: rtpg failed, result 458752
>
> MAINTENANCE_IN now returns success to avoid the error path as
> is currently done with INQUIRY and MODE_SENSE.
>
> Suggested-by: Michael Kelley <mhklinux@outlook.com>
> Signed-off-by: Cathy Avery <cavery@redhat.com>
> ---
> Changes since v1:
> - Handle error and logging by returning success as previously
>   done with INQUIRY and MODE_SENSE [Michael Kelley].
> ---
>  drivers/scsi/storvsc_drv.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index 7ceb982040a5..d0b55c1fa908 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -149,6 +149,8 @@ struct hv_fc_wwn_packet {
>  */
>  static int vmstor_proto_version;
>
> +static bool hv_dev_is_fc(struct hv_device *hv_dev);
> +
>  #define STORVSC_LOGGING_NONE   0
>  #define STORVSC_LOGGING_ERROR  1
>  #define STORVSC_LOGGING_WARN   2
> @@ -1138,6 +1140,7 @@ static void storvsc_on_io_completion(struct storvsc_device *stor_device,
>          * not correctly handle:
>          * INQUIRY command with page code parameter set to 0x80
>          * MODE_SENSE command with cmd[2] == 0x1c
> +        * MAINTENANCE_IN is not supported by HyperV FC passthrough
>          *
>          * Setup srb and scsi status so this won't be fatal.
>          * We do this so we can distinguish truly fatal failues
> @@ -1145,7 +1148,9 @@ static void storvsc_on_io_completion(struct storvsc_device *stor_device,
>          */
>
>         if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
> -          (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
> +          (stor_pkt->vm_srb.cdb[0] == MODE_SENSE) ||
> +          (stor_pkt->vm_srb.cdb[0] == MAINTENANCE_IN &&
> +          hv_dev_is_fc(device))) {
>                 vstor_packet->vm_srb.scsi_status = 0;
>                 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
>         }
> --
> 2.42.0
>

Reviewed-by: Ewan D. Milne <emilne@redhat.com>