[PATCH 0/3] scsi: Some miscellaneous fixes

[PATCH 0/3] scsi: Some miscellaneous fixes

[K. Y. Srinivasan]

Some miscellaneous fixes.

K. Y. Srinivasan (1):
  storvsc: Don't set the SRB_FLAGS_QUEUE_ACTION_ENABLE flag

Vitaly Kuznetsov (2):
  scsi_scan: don't dump trace when scsi_prep_async_scan() is called
    twice
  scsi: introduce short_inquiry flag for broken host adapters

 drivers/scsi/scsi_scan.c   |   10 +++++-----
 drivers/scsi/storvsc_drv.c |    4 ++--
 include/scsi/scsi_host.h   |    6 ++++++
 3 files changed, 13 insertions(+), 7 deletions(-)

-- 
1.7.4.1

[PATCH 1/3] scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice

[K. Y. Srinivasan]

From: Vitaly Kuznetsov <vkuznets@redhat.com>

The only user of scsi_prep_async_scan() is scsi_scan_host() and it handles
the situation correctly. Move 'called twice' reporting to debug level as
well.

The issue is observed on Hyper-V: on any device add/remove event storvsc
driver calls scsi_scan_host() and in case previous scan is still running
we get the message and stack dump on console.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
 drivers/scsi/scsi_scan.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index f9f3f82..01ad016 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1712,8 +1712,7 @@ static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
 		return NULL;
 
 	if (shost->async_scan) {
-		shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
-		dump_stack();
+		shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__);
 		return NULL;
 	}
 
-- 
1.7.4.1

[PATCH 1/3] scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice

[K. Y. Srinivasan]

From: Vitaly Kuznetsov <vkuznets@redhat.com>

The only user of scsi_prep_async_scan() is scsi_scan_host() and it handles
the situation correctly. Move 'called twice' reporting to debug level as
well.

The issue is observed on Hyper-V: on any device add/remove event storvsc
driver calls scsi_scan_host() and in case previous scan is still running
we get the message and stack dump on console.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
 drivers/scsi/scsi_scan.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index f9f3f82..01ad016 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1712,8 +1712,7 @@ static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
 		return NULL;
 
 	if (shost->async_scan) {
-		shost_printk(KERN_INFO, shost, "%s called twice\n", __func__);
-		dump_stack();
+		shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__);
 		return NULL;
 	}
 
-- 
1.7.4.1

[PATCH 2/3] scsi: introduce short_inquiry flag for broken host adapters

[K. Y. Srinivasan]

From: Vitaly Kuznetsov <vkuznets@redhat.com>

Some host adapters (e.g. Hyper-V storvsc) are known for not respecting the
SPC-2/3/4 requirement for 'INQUIRY data (see table ...) shall contain at
least 36 bytes'. As a result we get tons on 'scsi 0:7:1:1: scsi scan:
INQUIRY result too short (5), using 36' messages on console. This can be
problematic for slow consoles. Introduce short_inquiry host template flag
to avoid printing error messages for such adapters.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
 drivers/scsi/scsi_scan.c   |    7 ++++---
 drivers/scsi/storvsc_drv.c |    1 +
 include/scsi/scsi_host.h   |    6 ++++++
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 01ad016..5e325ce 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -701,9 +701,10 @@ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
 	 * strings.
 	 */
 	if (sdev->inquiry_len < 36) {
-		sdev_printk(KERN_INFO, sdev,
-			    "scsi scan: INQUIRY result too short (%d),"
-			    " using 36\n", sdev->inquiry_len);
+		if (!sdev->host->hostt->short_inquiry)
+			sdev_printk(KERN_INFO, sdev,
+				    "scsi scan: INQUIRY result too short (%d),"
+				    " using 36\n", sdev->inquiry_len);
 		sdev->inquiry_len = 36;
 	}
 
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 40c43ae..bce131b 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1781,6 +1781,7 @@ static struct scsi_host_template scsi_driver = {
 	/* Make sure we dont get a sg segment crosses a page boundary */
 	.dma_boundary =		PAGE_SIZE-1,
 	.no_write_same =	1,
+	.short_inquiry =	1,
 };
 
 enum {
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index e113c75..7b022af 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -454,6 +454,12 @@ struct scsi_host_template {
 	unsigned no_async_abort:1;
 
 	/*
+	 * True if this host adapter returns short (<36 bytes) responses to
+	 * some INQUIRY requests.
+	 */
+	unsigned short_inquiry:1;
+
+	/*
 	 * Countdown for host blocking with no commands outstanding.
 	 */
 	unsigned int max_host_blocked;
-- 
1.7.4.1

[PATCH 2/3] scsi: introduce short_inquiry flag for broken host adapters

[K. Y. Srinivasan]

From: Vitaly Kuznetsov <vkuznets@redhat.com>

Some host adapters (e.g. Hyper-V storvsc) are known for not respecting the
SPC-2/3/4 requirement for 'INQUIRY data (see table ...) shall contain at
least 36 bytes'. As a result we get tons on 'scsi 0:7:1:1: scsi scan:
INQUIRY result too short (5), using 36' messages on console. This can be
problematic for slow consoles. Introduce short_inquiry host template flag
to avoid printing error messages for such adapters.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
---
 drivers/scsi/scsi_scan.c   |    7 ++++---
 drivers/scsi/storvsc_drv.c |    1 +
 include/scsi/scsi_host.h   |    6 ++++++
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 01ad016..5e325ce 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -701,9 +701,10 @@ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
 	 * strings.
 	 */
 	if (sdev->inquiry_len < 36) {
-		sdev_printk(KERN_INFO, sdev,
-			    "scsi scan: INQUIRY result too short (%d),"
-			    " using 36\n", sdev->inquiry_len);
+		if (!sdev->host->hostt->short_inquiry)
+			sdev_printk(KERN_INFO, sdev,
+				    "scsi scan: INQUIRY result too short (%d),"
+				    " using 36\n", sdev->inquiry_len);
 		sdev->inquiry_len = 36;
 	}
 
diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 40c43ae..bce131b 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1781,6 +1781,7 @@ static struct scsi_host_template scsi_driver = {
 	/* Make sure we dont get a sg segment crosses a page boundary */
 	.dma_boundary =		PAGE_SIZE-1,
 	.no_write_same =	1,
+	.short_inquiry =	1,
 };
 
 enum {
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index e113c75..7b022af 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -454,6 +454,12 @@ struct scsi_host_template {
 	unsigned no_async_abort:1;
 
 	/*
+	 * True if this host adapter returns short (<36 bytes) responses to
+	 * some INQUIRY requests.
+	 */
+	unsigned short_inquiry:1;
+
+	/*
 	 * Countdown for host blocking with no commands outstanding.
 	 */
 	unsigned int max_host_blocked;
-- 
1.7.4.1

[PATCH RESEND 3/3] storvsc: Don't set the SRB_FLAGS_QUEUE_ACTION_ENABLE flag

[K. Y. Srinivasan]

Don't set the SRB_FLAGS_QUEUE_ACTION_ENABLE flag since we are not specifying
tags. Qlogic driver does not work correctly if the SRB_FLAGS_QUEUE_ACTION_ENABLE
is set and no action tag is specified.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Vivek Yadav <vyadav@microsoft.com>
Reviewed-by: Long Li <longli@microsoft.com>
---
 drivers/scsi/storvsc_drv.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index bce131b..9c8db21 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1647,8 +1647,7 @@ static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
 	vm_srb->win8_extension.time_out_value = 60;
 
 	vm_srb->win8_extension.srb_flags |=
-		(SRB_FLAGS_QUEUE_ACTION_ENABLE |
-		SRB_FLAGS_DISABLE_SYNCH_TRANSFER);
+		SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
 
 	/* Build the SRB */
 	switch (scmnd->sc_data_direction) {
-- 
1.7.4.1

Re: [PATCH 0/3] scsi: Some miscellaneous fixes

[Vitaly Kuznetsov]

"K. Y. Srinivasan" <kys@microsoft.com> writes:

[...]

>
> Vitaly Kuznetsov (2):
>   scsi_scan: don't dump trace when scsi_prep_async_scan() is called
>     twice
>   scsi: introduce short_inquiry flag for broken host adapters

James,

I'm sorry for the annoyance but when I asked about these patches last
time you said we don't have them reviewed. Is it OK now when we have
signed-off-by: from K. Y. or do we need to ask someone else?

Thanks,

-- 
  Vitaly

RE: [PATCH 0/3] scsi: Some miscellaneous fixes

[KY Srinivasan]

> -----Original Message-----
> From: Vitaly Kuznetsov [mailto:vkuznets@redhat.com]
> Sent: Tuesday, September 29, 2015 6:34 AM
> To: James E.J. Bottomley <JBottomley@odin.com>; KY Srinivasan
> <kys@microsoft.com>
> Cc: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org;
> devel@linuxdriverproject.org; ohering@suse.com;
> jbottomley@parallels.com; hch@infradead.org; linux-scsi@vger.kernel.org;
> apw@canonical.com; jasowang@redhat.com
> Subject: Re: [PATCH 0/3] scsi: Some miscellaneous fixes
> 
> "K. Y. Srinivasan" <kys@microsoft.com> writes:
> 
> [...]
> 
> >
> > Vitaly Kuznetsov (2):
> >   scsi_scan: don't dump trace when scsi_prep_async_scan() is called
> >     twice
> >   scsi: introduce short_inquiry flag for broken host adapters
> 
> James,
> 
> I'm sorry for the annoyance but when I asked about these patches last
> time you said we don't have them reviewed. Is it OK now when we have
> signed-off-by: from K. Y. or do we need to ask someone else?

We have tested these patches on various Hyper-V platforms. 

K. Y
> 
> Thanks,
> 
> --
>   Vitaly