Re: [PATCH v3] mptfusion: enable no_write_same for vmware scsi disks
On 09/23/2014 09:22 AM, Chris J Arges wrote: > When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used > data can be improperly zeroed out using the mptfusion driver. This patch > disables write_same for this driver and the vmware subsystem_vendor which > ensures that manual zeroing out is used instead. > > BugLink: http://bugs.launchpad.net/bugs/1371591 > Reported-by: Bruce Lucas > Tested-by: Chris J Arges > Signed-off-by: Chris J Arges > --- > drivers/message/fusion/mptspi.c | 5 + > 1 file changed, 5 insertions(+) > > diff --git a/drivers/message/fusion/mptspi.c b/drivers/message/fusion/mptspi.c > index 787933d..613231c 100644 > --- a/drivers/message/fusion/mptspi.c > +++ b/drivers/message/fusion/mptspi.c > @@ -1419,6 +1419,11 @@ mptspi_probe(struct pci_dev *pdev, const struct > pci_device_id *id) > goto out_mptspi_probe; > } > > + /* VMWare emulation doesn't properly implement WRITE_SAME > + */ > + if (pdev->subsystem_vendor == 0x15AD) > + sh->no_write_same = 1; > + > spin_lock_irqsave(&ioc->FreeQlock, flags); > > /* Attach the SCSI Host to the IOC structure > As a workaround one can do the following: # Set the scsi disk max_write_same_blocks to 0 to disable write_same. (Your paths may vary...) echo 0 > /sys/devices/pci:00/:00:10.0/host32/target32:0:0/32:0:0:0/scsi_disk/32:0:0:0/max_write_same_blocks # Force the dm device to reload (thus calling dm_table_set_restrictions and checking for the new max_write_same_blocks value) dmsetup table /dev/dm-0 save dmsetup suspend /dev/dm-0; dmsetup reload /dev/dm-0 save; dmsetup resume /dev/dm-0 # Now the dm device shows write_same_max_bytes as 0 cat /sys/block/dm-0/queue/write_same_max_bytes # Run the test case in the original bug, it now passes. So a few questions: 1) Does this workaround make sense? Perhaps there is an easier way? 2) Do we expect changing max_write_same_blocks at the scsi_disk level to propagate the right write_same flags to other layers such as dm? 3) In light of this workaround, does this patch still make sense? Would there be a better layer to fix this? Thanks, --chris j arges -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] mptfusion: enable no_write_same for vmware scsi disks
On 09/23/2014 09:22 AM, Chris J Arges wrote: > When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used > data can be improperly zeroed out using the mptfusion driver. This patch > disables write_same for this driver and the vmware subsystem_vendor which > ensures that manual zeroing out is used instead. > Please hold off on applying this, I'm pursuing a different approach to solving this bug that may be more optimal than adding this quirk. Thanks, --chris j arges > BugLink: http://bugs.launchpad.net/bugs/1371591 > Reported-by: Bruce Lucas > Tested-by: Chris J Arges > Signed-off-by: Chris J Arges > --- > drivers/message/fusion/mptspi.c | 5 + > 1 file changed, 5 insertions(+) > > diff --git a/drivers/message/fusion/mptspi.c b/drivers/message/fusion/mptspi.c > index 787933d..613231c 100644 > --- a/drivers/message/fusion/mptspi.c > +++ b/drivers/message/fusion/mptspi.c > @@ -1419,6 +1419,11 @@ mptspi_probe(struct pci_dev *pdev, const struct > pci_device_id *id) > goto out_mptspi_probe; > } > > + /* VMWare emulation doesn't properly implement WRITE_SAME > + */ > + if (pdev->subsystem_vendor == 0x15AD) > + sh->no_write_same = 1; > + > spin_lock_irqsave(&ioc->FreeQlock, flags); > > /* Attach the SCSI Host to the IOC structure > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH v3] mptfusion: enable no_write_same for vmware scsi disks
When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used data can be improperly zeroed out using the mptfusion driver. This patch disables write_same for this driver and the vmware subsystem_vendor which ensures that manual zeroing out is used instead. BugLink: http://bugs.launchpad.net/bugs/1371591 Reported-by: Bruce Lucas Tested-by: Chris J Arges Signed-off-by: Chris J Arges --- drivers/message/fusion/mptspi.c | 5 + 1 file changed, 5 insertions(+) diff --git a/drivers/message/fusion/mptspi.c b/drivers/message/fusion/mptspi.c index 787933d..613231c 100644 --- a/drivers/message/fusion/mptspi.c +++ b/drivers/message/fusion/mptspi.c @@ -1419,6 +1419,11 @@ mptspi_probe(struct pci_dev *pdev, const struct pci_device_id *id) goto out_mptspi_probe; } + /* VMWare emulation doesn't properly implement WRITE_SAME +*/ + if (pdev->subsystem_vendor == 0x15AD) + sh->no_write_same = 1; + spin_lock_irqsave(&ioc->FreeQlock, flags); /* Attach the SCSI Host to the IOC structure -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v2] mptfusion: enable no_write_same for vmware scsi disks
On 09/22/2014 03:44 PM, Chris J Arges wrote:
> When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used
> data can be improperly zeroed out using the mptfusion driver. This patch
> disables write_same for this driver and the vmware subsystem_vendor which
> ensures that manual zeroing out is used instead.
>
> BugLink: http://bugs.launchpad.net/bugs/1371591
> Reported-by: Bruce Lucas
> Tested-by: Chris J Arges
> Signed-off-by: Chris J Arges
> ---
> drivers/message/fusion/mptspi.c | 6 ++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/message/fusion/mptspi.c b/drivers/message/fusion/mptspi.c
> index 787933d..fca1594 100644
> --- a/drivers/message/fusion/mptspi.c
> +++ b/drivers/message/fusion/mptspi.c
> @@ -1409,6 +1409,12 @@ mptspi_probe(struct pci_dev *pdev, const struct
> pci_device_id *id)
> return 0;
> }
>
> + /* Fix for vmware guests that do not implement write_same
> + */
> + if (pdev->subsystem_vendor == 0x15AD) {
> + mptspi_driver_template.no_write_same = 1;
> + }
> +
> sh = scsi_host_alloc(&mptspi_driver_template, sizeof(MPT_SCSI_HOST));
>
> if (!sh) {
>
This is a do-no-harm patch, with a case to check for vmware
subsystem_vendor as suggested by Christoph. Let me know if there are
issues with this patch (do I need a define for the vendor ID? Is the
comment a little too vague or unnecessary?)
Adding those that were CC'ed in the other part of the thread.
Thanks,
--chris j arges
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[PATCH v2] mptfusion: enable no_write_same for vmware scsi disks
When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used
data can be improperly zeroed out using the mptfusion driver. This patch
disables write_same for this driver and the vmware subsystem_vendor which
ensures that manual zeroing out is used instead.
BugLink: http://bugs.launchpad.net/bugs/1371591
Reported-by: Bruce Lucas
Tested-by: Chris J Arges
Signed-off-by: Chris J Arges
---
drivers/message/fusion/mptspi.c | 6 ++
1 file changed, 6 insertions(+)
diff --git a/drivers/message/fusion/mptspi.c b/drivers/message/fusion/mptspi.c
index 787933d..fca1594 100644
--- a/drivers/message/fusion/mptspi.c
+++ b/drivers/message/fusion/mptspi.c
@@ -1409,6 +1409,12 @@ mptspi_probe(struct pci_dev *pdev, const struct
pci_device_id *id)
return 0;
}
+ /* Fix for vmware guests that do not implement write_same
+ */
+ if (pdev->subsystem_vendor == 0x15AD) {
+ mptspi_driver_template.no_write_same = 1;
+ }
+
sh = scsi_host_alloc(&mptspi_driver_template, sizeof(MPT_SCSI_HOST));
if (!sh) {
--
1.9.1
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Re: [PATCH] mptfusion: enable no_write_same in scsi_host_template
On 09/22/2014 01:19 PM, Christoph Hellwig wrote: > On Mon, Sep 22, 2014 at 01:17:01PM -0500, Chris J Arges wrote: >>> >> I've only been able to reproduce this on VMWare. There is a pretty >> straightforward reproducer in the BugLink if there is any interest in >> verifying on hardware. >> >> How would you recommending blacklisting only VMWare guests in this case? > > Can you check what PCI subdevice and subvendor IDs the device you can > reproduce it with have? If the subvendor is Vmware that would be easy, > if not the Avago people might be able to help with a device specific > VMware identification. If that fails we have kernel helpers to > identify the hypervisor, but I'd rather avoid that as it would also > trigger for PCI pass through devices. > Christoph, Thanks for the input, and now I realize how broad the earlier patch was. I'll see if I can quirk on the vendor ID to enable no_write_same, in the meantime I'll see if there are any ways to fix the underlying issue without adding such a quirk. Thanks, --chris j arges -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH] mptfusion: enable no_write_same in scsi_host_template
On 09/22/2014 01:02 PM, Christoph Hellwig wrote: > On Mon, Sep 22, 2014 at 12:56:59PM -0500, Chris J Arges wrote: >> When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used >> data can be improperly zeroed out using the mptfusion driver. This patch >> disables write_same for this driver which ensures that manual zeroing out >> is used instead. > > Does this affet real hardware or is it a VMware bug? If it's just the > latter we should simply blacklist VMware. > I've only been able to reproduce this on VMWare. There is a pretty straightforward reproducer in the BugLink if there is any interest in verifying on hardware. How would you recommending blacklisting only VMWare guests in this case? Thanks, --chris j arges -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[PATCH] mptfusion: enable no_write_same in scsi_host_template
When using a virtual SCSI disk in a VMWare VM if blkdev_issue_zeroout is used
data can be improperly zeroed out using the mptfusion driver. This patch
disables write_same for this driver which ensures that manual zeroing out
is used instead.
BugLink: http://bugs.launchpad.net/bugs/1371591
Reported-by: Bruce Lucas
Signed-off-by: Chris J Arges
---
drivers/message/fusion/mptspi.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/message/fusion/mptspi.c b/drivers/message/fusion/mptspi.c
index 787933d..2fcc9bd 100644
--- a/drivers/message/fusion/mptspi.c
+++ b/drivers/message/fusion/mptspi.c
@@ -850,6 +850,7 @@ static struct scsi_host_template mptspi_driver_template = {
.cmd_per_lun= 7,
.use_clustering = ENABLE_CLUSTERING,
.shost_attrs= mptscsih_host_attrs,
+ .no_write_same = 1,
};
static int mptspi_write_spi_device_pg1(struct scsi_target *starget,
--
1.9.1
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