[PATCH] qla2xxx: do not abort all commands in the adapter during EEH recovery

[PATCH] qla2xxx: do not abort all commands in the adapter during EEH recovery

[Mauricio Faria de Oliveira]

The previous commit ("qla2xxx: fix invalid DMA access after command
aborts in PCI device remove") introduced a regression during an EEH
recovery, since the change to the qla2x00_abort_all_cmds() function
calls qla2xxx_eh_abort(), which verifies the EEH recovery condition
but handles it heavy-handed. (commit a465537ad1a4 "qla2xxx: Disable
the adapter and skip error recovery in case of register disconnect.")

This problem warrants a more general/optimistic solution right into
qla2xxx_eh_abort()  (eg in case a real command abort arrives during
EEH recovery, or if it takes long enough to trigger command aborts);
but it's still worth to add a check to ensure the code added by the
previous commit is correct and contained within its owner function.

This commit just adds a 'if (!ha->flags.eeh_busy)' check around it.
(ahem; a trivial fix for this -rc series; sorry for this oversight.)

With it applied, both PCI device remove and EEH recovery works fine.

Fixes: 1535aa75a3d8 ("scsi: qla2xxx: fix invalid DMA access after
command aborts in PCI device remove")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
---
 drivers/scsi/qla2xxx/qla_os.c | 21 +++++++++++++--------
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 567fa080e261..56d6142852a5 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -1456,15 +1456,20 @@ uint32_t qla2x00_isp_reg_stat(struct qla_hw_data *ha)
 		for (cnt = 1; cnt < req->num_outstanding_cmds; cnt++) {
 			sp = req->outstanding_cmds[cnt];
 			if (sp) {
-				/* Get a reference to the sp and drop the lock.
-				 * The reference ensures this sp->done() call
-				 * - and not the call in qla2xxx_eh_abort() -
-				 * ends the SCSI command (with result 'res').
+				/* Don't abort commands in adapter during EEH
+				 * recovery as it's not accessible/responding.
 				 */
-				sp_get(sp);
-				spin_unlock_irqrestore(&ha->hardware_lock, flags);
-				qla2xxx_eh_abort(GET_CMD_SP(sp));
-				spin_lock_irqsave(&ha->hardware_lock, flags);
+				if (!ha->flags.eeh_busy) {
+					/* Get a reference to the sp and drop the lock.
+					 * The reference ensures this sp->done() call
+					 * - and not the call in qla2xxx_eh_abort() -
+					 * ends the SCSI command (with result 'res').
+					 */
+					sp_get(sp);
+					spin_unlock_irqrestore(&ha->hardware_lock, flags);
+					qla2xxx_eh_abort(GET_CMD_SP(sp));
+					spin_lock_irqsave(&ha->hardware_lock, flags);
+				}
 				req->outstanding_cmds[cnt] = NULL;
 				sp->done(vha, sp, res);
 			}
-- 
1.8.3.1

Re: [PATCH] qla2xxx: do not abort all commands in the adapter during EEH recovery

[Madhani, Himanshu]

On 11/14/16, 1:26 PM, "Mauricio Faria de Oliveira" <mauricfo@linux.vnet.ibm.com> wrote:

>The previous commit ("qla2xxx: fix invalid DMA access after command
>aborts in PCI device remove") introduced a regression during an EEH
>recovery, since the change to the qla2x00_abort_all_cmds() function
>calls qla2xxx_eh_abort(), which verifies the EEH recovery condition
>but handles it heavy-handed. (commit a465537ad1a4 "qla2xxx: Disable
>the adapter and skip error recovery in case of register disconnect.")
>
>This problem warrants a more general/optimistic solution right into
>qla2xxx_eh_abort()  (eg in case a real command abort arrives during
>EEH recovery, or if it takes long enough to trigger command aborts);
>but it's still worth to add a check to ensure the code added by the
>previous commit is correct and contained within its owner function.
>
>This commit just adds a 'if (!ha->flags.eeh_busy)' check around it.
>(ahem; a trivial fix for this -rc series; sorry for this oversight.)
>
>With it applied, both PCI device remove and EEH recovery works fine.
>
>Fixes: 1535aa75a3d8 ("scsi: qla2xxx: fix invalid DMA access after
>command aborts in PCI device remove")
>Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
>---
> drivers/scsi/qla2xxx/qla_os.c | 21 +++++++++++++--------
> 1 file changed, 13 insertions(+), 8 deletions(-)
>
>diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
>index 567fa080e261..56d6142852a5 100644
>--- a/drivers/scsi/qla2xxx/qla_os.c
>+++ b/drivers/scsi/qla2xxx/qla_os.c
>@@ -1456,15 +1456,20 @@ uint32_t qla2x00_isp_reg_stat(struct qla_hw_data *ha)
> 		for (cnt = 1; cnt < req->num_outstanding_cmds; cnt++) {
> 			sp = req->outstanding_cmds[cnt];
> 			if (sp) {
>-				/* Get a reference to the sp and drop the lock.
>-				 * The reference ensures this sp->done() call
>-				 * - and not the call in qla2xxx_eh_abort() -
>-				 * ends the SCSI command (with result 'res').
>+				/* Don't abort commands in adapter during EEH
>+				 * recovery as it's not accessible/responding.
> 				 */
>-				sp_get(sp);
>-				spin_unlock_irqrestore(&ha->hardware_lock, flags);
>-				qla2xxx_eh_abort(GET_CMD_SP(sp));
>-				spin_lock_irqsave(&ha->hardware_lock, flags);
>+				if (!ha->flags.eeh_busy) {
>+					/* Get a reference to the sp and drop the lock.
>+					 * The reference ensures this sp->done() call
>+					 * - and not the call in qla2xxx_eh_abort() -
>+					 * ends the SCSI command (with result 'res').
>+					 */
>+					sp_get(sp);
>+					spin_unlock_irqrestore(&ha->hardware_lock, flags);
>+					qla2xxx_eh_abort(GET_CMD_SP(sp));
>+					spin_lock_irqsave(&ha->hardware_lock, flags);
>+				}
> 				req->outstanding_cmds[cnt] = NULL;
> 				sp->done(vha, sp, res);
> 			}
>-- 
>1.8.3.1
>

Acked-by: Himanshu Madhani <himanshu.madhani@cavium.com>

Thanks,
Himanshu

Re: [PATCH] qla2xxx: do not abort all commands in the adapter during EEH recovery

[Martin K. Petersen]

>>>>> "Mauricio" == Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com> writes:

Mauricio> The previous commit ("qla2xxx: fix invalid DMA access after
Mauricio> command aborts in PCI device remove") introduced a regression
Mauricio> during an EEH recovery, since the change to the
Mauricio> qla2x00_abort_all_cmds() function calls qla2xxx_eh_abort(),
Mauricio> which verifies the EEH recovery condition but handles it
Mauricio> heavy-handed. (commit a465537ad1a4 "qla2xxx: Disable the
Mauricio> adapter and skip error recovery in case of register
Mauricio> disconnect.")

Applied to 4.9/scsi-fixes.

-- 
Martin K. Petersen	Oracle Linux Engineering