[PATCH v3 0/3] PCI: Disable parity checking if broken_parity is set

[PATCH v3 0/3] PCI: Disable parity checking if broken_parity is set

[Heiner Kallweit]

If we know that a device has broken parity checking, then disable it.
This avoids quirks like in r8169 where on the first parity error
interrupt parity checking will be disabled if broken_parity_status
is set. Make pci_quirk_broken_parity() public so that it can be used
by platform code, e.g. for Thecus N2100.

v2:
- reduce scope of N2100 change to using the new PCI core quirk
v3:
- improve commit message of patch 2

Heiner Kallweit (3):
  PCI: Disable parity checking if broken_parity_status is set
  ARM: iop32x: improve N2100 PCI broken parity quirk
  r8169: simplify broken parity handling now that PCI core takes care

 arch/arm/mach-iop32x/n2100.c              |  2 +-
 drivers/net/ethernet/realtek/r8169_main.c | 14 --------------
 drivers/pci/quirks.c                      | 17 +++++++++++------
 include/linux/pci.h                       |  2 ++
 4 files changed, 14 insertions(+), 21 deletions(-)

-- 
2.30.0

[PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Heiner Kallweit]

If we know that a device has broken parity checking, then disable it.
This avoids quirks like in r8169 where on the first parity error
interrupt parity checking will be disabled if broken_parity_status
is set. Make pci_quirk_broken_parity() public so that it can be used
by platform code, e.g. for Thecus N2100.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/pci/quirks.c | 17 +++++++++++------
 include/linux/pci.h  |  2 ++
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 653660e3b..ab54e26b8 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
 				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
 
+void pci_quirk_broken_parity(struct pci_dev *dev)
+{
+	u16 cmd;
+
+	dev->broken_parity_status = 1;	/* This device gives false positives */
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
+}
+
 /*
  * The Mellanox Tavor device gives false positive parity errors.  Mark this
  * device with a broken_parity_status to allow PCI scanning code to "skip"
  * this now blacklisted device.
  */
-static void quirk_mellanox_tavor(struct pci_dev *dev)
-{
-	dev->broken_parity_status = 1;	/* This device gives false positives */
-}
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
 
 /*
  * Deal with broken BIOSes that neglect to enable passive release,
diff --git a/include/linux/pci.h b/include/linux/pci.h
index b32126d26..161dcc474 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
 	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
 };
 
+void pci_quirk_broken_parity(struct pci_dev *dev);
+
 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
 #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
 				    class_shift, hook)			\
-- 
2.30.0

[PATCH v3 2/3] ARM: iop32x: improve N2100 PCI broken parity quirk

[Heiner Kallweit]

Use new PCI core function pci_quirk_broken_parity() to disable
parity checking.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- remove additional changes from this patch
v3:
- improve commit message
---
 arch/arm/mach-iop32x/n2100.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/mach-iop32x/n2100.c b/arch/arm/mach-iop32x/n2100.c
index 78b9a5ee4..9f2aae3cd 100644
--- a/arch/arm/mach-iop32x/n2100.c
+++ b/arch/arm/mach-iop32x/n2100.c
@@ -125,7 +125,7 @@ static void n2100_fixup_r8169(struct pci_dev *dev)
 	if (dev->bus->number == 0 &&
 	    (dev->devfn == PCI_DEVFN(1, 0) ||
 	     dev->devfn == PCI_DEVFN(2, 0)))
-		dev->broken_parity_status = 1;
+		pci_quirk_broken_parity(dev);
 }
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_REALTEK, PCI_ANY_ID, n2100_fixup_r8169);
 
-- 
2.30.0

[PATCH v3 3/3] r8169: simplify broken parity handling now that PCI core takes care

[Heiner Kallweit]

Meanwhile the PCI core disables parity checking for a device that has
broken_parity_status set. Therefore we don't need the quirk any longer
to disable parity checking on the first parity error interrupt.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 14 --------------
 1 file changed, 14 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index c9abc7ccb..024042f37 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4329,20 +4329,6 @@ static void rtl8169_pcierr_interrupt(struct net_device *dev)
 	if (net_ratelimit())
 		netdev_err(dev, "PCI error (cmd = 0x%04x, status_errs = 0x%04x)\n",
 			   pci_cmd, pci_status_errs);
-	/*
-	 * The recovery sequence below admits a very elaborated explanation:
-	 * - it seems to work;
-	 * - I did not see what else could be done;
-	 * - it makes iop3xx happy.
-	 *
-	 * Feel free to adjust to your needs.
-	 */
-	if (pdev->broken_parity_status)
-		pci_cmd &= ~PCI_COMMAND_PARITY;
-	else
-		pci_cmd |= PCI_COMMAND_SERR | PCI_COMMAND_PARITY;
-
-	pci_write_config_word(pdev, PCI_COMMAND, pci_cmd);
 
 	rtl_schedule_task(tp, RTL_FLAG_TASK_RESET_PENDING);
 }
-- 
2.30.0

Re: [PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Bjorn Helgaas]

On Wed, Jan 06, 2021 at 06:50:22PM +0100, Heiner Kallweit wrote:
> If we know that a device has broken parity checking, then disable it.
> This avoids quirks like in r8169 where on the first parity error
> interrupt parity checking will be disabled if broken_parity_status
> is set. Make pci_quirk_broken_parity() public so that it can be used
> by platform code, e.g. for Thecus N2100.
> 
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>

Acked-by: Bjorn Helgaas <bhelgaas@google.com>

This series should all go together.  Let me know if you want me to do
anything more (would require acks for arm and r8169, of course).

> ---
>  drivers/pci/quirks.c | 17 +++++++++++------
>  include/linux/pci.h  |  2 ++
>  2 files changed, 13 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 653660e3b..ab54e26b8 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
>  DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
>  				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
>  
> +void pci_quirk_broken_parity(struct pci_dev *dev)
> +{
> +	u16 cmd;
> +
> +	dev->broken_parity_status = 1;	/* This device gives false positives */
> +	pci_read_config_word(dev, PCI_COMMAND, &cmd);
> +	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
> +}
> +
>  /*
>   * The Mellanox Tavor device gives false positive parity errors.  Mark this
>   * device with a broken_parity_status to allow PCI scanning code to "skip"
>   * this now blacklisted device.
>   */
> -static void quirk_mellanox_tavor(struct pci_dev *dev)
> -{
> -	dev->broken_parity_status = 1;	/* This device gives false positives */
> -}
> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
>  
>  /*
>   * Deal with broken BIOSes that neglect to enable passive release,
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index b32126d26..161dcc474 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
>  	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
>  };
>  
> +void pci_quirk_broken_parity(struct pci_dev *dev);
> +
>  #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
>  #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
>  				    class_shift, hook)			\
> -- 
> 2.30.0
> 
> 
> 

Re: [PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Heiner Kallweit]

On 06.01.2021 20:22, Bjorn Helgaas wrote:
> On Wed, Jan 06, 2021 at 06:50:22PM +0100, Heiner Kallweit wrote:
>> If we know that a device has broken parity checking, then disable it.
>> This avoids quirks like in r8169 where on the first parity error
>> interrupt parity checking will be disabled if broken_parity_status
>> is set. Make pci_quirk_broken_parity() public so that it can be used
>> by platform code, e.g. for Thecus N2100.
>>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> 
> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
> 
> This series should all go together.  Let me know if you want me to do
> anything more (would require acks for arm and r8169, of course).
> 
Right. For r8169 I'm the maintainer myself and agreed with Jakub that
the r8169 patch will go through the PCI tree.

Regarding the arm/iop32x part:
MAINTAINERS file lists Lennert as maintainer, let me add him.
Strange thing is that the MAINTAINERS entry for arm/iop32x has no
F entry, therefore the get_maintainers scripts will never list him
as addressee. The script lists Russell as "odd fixer".
@Lennert: Please provide a patch to add the missing F entry.

ARM/INTEL IOP32X ARM ARCHITECTURE
M:	Lennert Buytenhek <kernel@wantstofly.org>
L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
S:	Maintained


>> ---
>>  drivers/pci/quirks.c | 17 +++++++++++------
>>  include/linux/pci.h  |  2 ++
>>  2 files changed, 13 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
>> index 653660e3b..ab54e26b8 100644
>> --- a/drivers/pci/quirks.c
>> +++ b/drivers/pci/quirks.c
>> @@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
>>  DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
>>  				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
>>  
>> +void pci_quirk_broken_parity(struct pci_dev *dev)
>> +{
>> +	u16 cmd;
>> +
>> +	dev->broken_parity_status = 1;	/* This device gives false positives */
>> +	pci_read_config_word(dev, PCI_COMMAND, &cmd);
>> +	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
>> +}
>> +
>>  /*
>>   * The Mellanox Tavor device gives false positive parity errors.  Mark this
>>   * device with a broken_parity_status to allow PCI scanning code to "skip"
>>   * this now blacklisted device.
>>   */
>> -static void quirk_mellanox_tavor(struct pci_dev *dev)
>> -{
>> -	dev->broken_parity_status = 1;	/* This device gives false positives */
>> -}
>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
>>  
>>  /*
>>   * Deal with broken BIOSes that neglect to enable passive release,
>> diff --git a/include/linux/pci.h b/include/linux/pci.h
>> index b32126d26..161dcc474 100644
>> --- a/include/linux/pci.h
>> +++ b/include/linux/pci.h
>> @@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
>>  	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
>>  };
>>  
>> +void pci_quirk_broken_parity(struct pci_dev *dev);
>> +
>>  #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
>>  #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
>>  				    class_shift, hook)			\
>> -- 
>> 2.30.0
>>
>>
>>

Re: [PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Heiner Kallweit]

On 06.01.2021 20:34, Heiner Kallweit wrote:
> On 06.01.2021 20:22, Bjorn Helgaas wrote:
>> On Wed, Jan 06, 2021 at 06:50:22PM +0100, Heiner Kallweit wrote:
>>> If we know that a device has broken parity checking, then disable it.
>>> This avoids quirks like in r8169 where on the first parity error
>>> interrupt parity checking will be disabled if broken_parity_status
>>> is set. Make pci_quirk_broken_parity() public so that it can be used
>>> by platform code, e.g. for Thecus N2100.
>>>
>>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
>>> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
>>
>> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
>>
>> This series should all go together.  Let me know if you want me to do
>> anything more (would require acks for arm and r8169, of course).
>>
> Right. For r8169 I'm the maintainer myself and agreed with Jakub that
> the r8169 patch will go through the PCI tree.
> 
> Regarding the arm/iop32x part:
> MAINTAINERS file lists Lennert as maintainer, let me add him.
> Strange thing is that the MAINTAINERS entry for arm/iop32x has no
> F entry, therefore the get_maintainers scripts will never list him
> as addressee. The script lists Russell as "odd fixer".
> @Lennert: Please provide a patch to add the missing F entry.
> 
> ARM/INTEL IOP32X ARM ARCHITECTURE
> M:	Lennert Buytenhek <kernel@wantstofly.org>
> L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
> S:	Maintained
> 

Bjorn, I saw that you set the series to "not applicable". Is this because
of the missing ack for the arm part?
I checked and Lennert's last kernel contribution is from 2015. Having said
that the maintainer's entry may be outdated. Not sure who else would be
entitled to ack this patch. The change is simple enough, could you take
it w/o an ack? 
Alternatively, IIRC Russell has got such a device. Russell, would it
be possible that you test that there's still no false-positive parity
errors with this series?


> 
>>> ---
>>>  drivers/pci/quirks.c | 17 +++++++++++------
>>>  include/linux/pci.h  |  2 ++
>>>  2 files changed, 13 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
>>> index 653660e3b..ab54e26b8 100644
>>> --- a/drivers/pci/quirks.c
>>> +++ b/drivers/pci/quirks.c
>>> @@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
>>>  DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
>>>  				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
>>>  
>>> +void pci_quirk_broken_parity(struct pci_dev *dev)
>>> +{
>>> +	u16 cmd;
>>> +
>>> +	dev->broken_parity_status = 1;	/* This device gives false positives */
>>> +	pci_read_config_word(dev, PCI_COMMAND, &cmd);
>>> +	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
>>> +}
>>> +
>>>  /*
>>>   * The Mellanox Tavor device gives false positive parity errors.  Mark this
>>>   * device with a broken_parity_status to allow PCI scanning code to "skip"
>>>   * this now blacklisted device.
>>>   */
>>> -static void quirk_mellanox_tavor(struct pci_dev *dev)
>>> -{
>>> -	dev->broken_parity_status = 1;	/* This device gives false positives */
>>> -}
>>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
>>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
>>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
>>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
>>>  
>>>  /*
>>>   * Deal with broken BIOSes that neglect to enable passive release,
>>> diff --git a/include/linux/pci.h b/include/linux/pci.h
>>> index b32126d26..161dcc474 100644
>>> --- a/include/linux/pci.h
>>> +++ b/include/linux/pci.h
>>> @@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
>>>  	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
>>>  };
>>>  
>>> +void pci_quirk_broken_parity(struct pci_dev *dev);
>>> +
>>>  #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
>>>  #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
>>>  				    class_shift, hook)			\
>>> -- 
>>> 2.30.0
>>>
>>>
>>>
> 

Re: [PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Bjorn Helgaas]

On Wed, Jan 13, 2021 at 09:52:23PM +0100, Heiner Kallweit wrote:
> On 06.01.2021 20:34, Heiner Kallweit wrote:
> > On 06.01.2021 20:22, Bjorn Helgaas wrote:
> >> On Wed, Jan 06, 2021 at 06:50:22PM +0100, Heiner Kallweit wrote:
> >>> If we know that a device has broken parity checking, then disable it.
> >>> This avoids quirks like in r8169 where on the first parity error
> >>> interrupt parity checking will be disabled if broken_parity_status
> >>> is set. Make pci_quirk_broken_parity() public so that it can be used
> >>> by platform code, e.g. for Thecus N2100.
> >>>
> >>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> >>> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> >>
> >> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
> >>
> >> This series should all go together.  Let me know if you want me to do
> >> anything more (would require acks for arm and r8169, of course).
> >>
> > Right. For r8169 I'm the maintainer myself and agreed with Jakub that
> > the r8169 patch will go through the PCI tree.
> > 
> > Regarding the arm/iop32x part:
> > MAINTAINERS file lists Lennert as maintainer, let me add him.
> > Strange thing is that the MAINTAINERS entry for arm/iop32x has no
> > F entry, therefore the get_maintainers scripts will never list him
> > as addressee. The script lists Russell as "odd fixer".
> > @Lennert: Please provide a patch to add the missing F entry.
> > 
> > ARM/INTEL IOP32X ARM ARCHITECTURE
> > M:	Lennert Buytenhek <kernel@wantstofly.org>
> > L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
> > S:	Maintained
> 
> Bjorn, I saw that you set the series to "not applicable". Is this because
> of the missing ack for the arm part?

No, it's because I screwed up.  I use "not applicable" when I expect
patches to go via another tree.  I just missed your note about merging
via the PCI tree.  I'll take a look soon.

> I checked and Lennert's last kernel contribution is from 2015. Having said
> that the maintainer's entry may be outdated. Not sure who else would be
> entitled to ack this patch. The change is simple enough, could you take
> it w/o an ack? 
> Alternatively, IIRC Russell has got such a device. Russell, would it
> be possible that you test that there's still no false-positive parity
> errors with this series?
> 
> 
> > 
> >>> ---
> >>>  drivers/pci/quirks.c | 17 +++++++++++------
> >>>  include/linux/pci.h  |  2 ++
> >>>  2 files changed, 13 insertions(+), 6 deletions(-)
> >>>
> >>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> >>> index 653660e3b..ab54e26b8 100644
> >>> --- a/drivers/pci/quirks.c
> >>> +++ b/drivers/pci/quirks.c
> >>> @@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
> >>>  DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
> >>>  				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
> >>>  
> >>> +void pci_quirk_broken_parity(struct pci_dev *dev)
> >>> +{
> >>> +	u16 cmd;
> >>> +
> >>> +	dev->broken_parity_status = 1;	/* This device gives false positives */
> >>> +	pci_read_config_word(dev, PCI_COMMAND, &cmd);
> >>> +	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
> >>> +}
> >>> +
> >>>  /*
> >>>   * The Mellanox Tavor device gives false positive parity errors.  Mark this
> >>>   * device with a broken_parity_status to allow PCI scanning code to "skip"
> >>>   * this now blacklisted device.
> >>>   */
> >>> -static void quirk_mellanox_tavor(struct pci_dev *dev)
> >>> -{
> >>> -	dev->broken_parity_status = 1;	/* This device gives false positives */
> >>> -}
> >>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
> >>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
> >>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
> >>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
> >>>  
> >>>  /*
> >>>   * Deal with broken BIOSes that neglect to enable passive release,
> >>> diff --git a/include/linux/pci.h b/include/linux/pci.h
> >>> index b32126d26..161dcc474 100644
> >>> --- a/include/linux/pci.h
> >>> +++ b/include/linux/pci.h
> >>> @@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
> >>>  	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
> >>>  };
> >>>  
> >>> +void pci_quirk_broken_parity(struct pci_dev *dev);
> >>> +
> >>>  #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
> >>>  #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
> >>>  				    class_shift, hook)			\
> >>> -- 
> >>> 2.30.0
> >>>
> >>>
> >>>
> > 
> 

Re: [PATCH v3 1/3] PCI: Disable parity checking if broken_parity is set

[Lennert Buytenhek]

On Wed, Jan 13, 2021 at 09:52:23PM +0100, Heiner Kallweit wrote:
> On 06.01.2021 20:34, Heiner Kallweit wrote:
> > On 06.01.2021 20:22, Bjorn Helgaas wrote:
> >> On Wed, Jan 06, 2021 at 06:50:22PM +0100, Heiner Kallweit wrote:
> >>> If we know that a device has broken parity checking, then disable it.
> >>> This avoids quirks like in r8169 where on the first parity error
> >>> interrupt parity checking will be disabled if broken_parity_status
> >>> is set. Make pci_quirk_broken_parity() public so that it can be used
> >>> by platform code, e.g. for Thecus N2100.
> >>>
> >>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> >>> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> >>
> >> Acked-by: Bjorn Helgaas <bhelgaas@google.com>
> >>
> >> This series should all go together.  Let me know if you want me to do
> >> anything more (would require acks for arm and r8169, of course).
> >>
> > Right. For r8169 I'm the maintainer myself and agreed with Jakub that
> > the r8169 patch will go through the PCI tree.
> > 
> > Regarding the arm/iop32x part:
> > MAINTAINERS file lists Lennert as maintainer, let me add him.
> > Strange thing is that the MAINTAINERS entry for arm/iop32x has no
> > F entry, therefore the get_maintainers scripts will never list him
> > as addressee. The script lists Russell as "odd fixer".
> > @Lennert: Please provide a patch to add the missing F entry.
> > 
> > ARM/INTEL IOP32X ARM ARCHITECTURE
> > M:	Lennert Buytenhek <kernel@wantstofly.org>
> > L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
> > S:	Maintained
> 
> Bjorn, I saw that you set the series to "not applicable". Is this because
> of the missing ack for the arm part?
> I checked and Lennert's last kernel contribution is from 2015. Having said
> that the maintainer's entry may be outdated. Not sure who else would be
> entitled to ack this patch. The change is simple enough, could you take
> it w/o an ack? 

This entry is indeed outdated, I don't have access to this
hardware anymore.


> Alternatively, IIRC Russell has got such a device. Russell, would it
> be possible that you test that there's still no false-positive parity
> errors with this series?
> 
> 
> > 
> >>> ---
> >>>  drivers/pci/quirks.c | 17 +++++++++++------
> >>>  include/linux/pci.h  |  2 ++
> >>>  2 files changed, 13 insertions(+), 6 deletions(-)
> >>>
> >>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> >>> index 653660e3b..ab54e26b8 100644
> >>> --- a/drivers/pci/quirks.c
> >>> +++ b/drivers/pci/quirks.c
> >>> @@ -205,17 +205,22 @@ static void quirk_mmio_always_on(struct pci_dev *dev)
> >>>  DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_ANY_ID, PCI_ANY_ID,
> >>>  				PCI_CLASS_BRIDGE_HOST, 8, quirk_mmio_always_on);
> >>>  
> >>> +void pci_quirk_broken_parity(struct pci_dev *dev)
> >>> +{
> >>> +	u16 cmd;
> >>> +
> >>> +	dev->broken_parity_status = 1;	/* This device gives false positives */
> >>> +	pci_read_config_word(dev, PCI_COMMAND, &cmd);
> >>> +	pci_write_config_word(dev, PCI_COMMAND, cmd & ~PCI_COMMAND_PARITY);
> >>> +}
> >>> +
> >>>  /*
> >>>   * The Mellanox Tavor device gives false positive parity errors.  Mark this
> >>>   * device with a broken_parity_status to allow PCI scanning code to "skip"
> >>>   * this now blacklisted device.
> >>>   */
> >>> -static void quirk_mellanox_tavor(struct pci_dev *dev)
> >>> -{
> >>> -	dev->broken_parity_status = 1;	/* This device gives false positives */
> >>> -}
> >>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, quirk_mellanox_tavor);
> >>> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, quirk_mellanox_tavor);
> >>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR, pci_quirk_broken_parity);
> >>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_MELLANOX, PCI_DEVICE_ID_MELLANOX_TAVOR_BRIDGE, pci_quirk_broken_parity);
> >>>  
> >>>  /*
> >>>   * Deal with broken BIOSes that neglect to enable passive release,
> >>> diff --git a/include/linux/pci.h b/include/linux/pci.h
> >>> index b32126d26..161dcc474 100644
> >>> --- a/include/linux/pci.h
> >>> +++ b/include/linux/pci.h
> >>> @@ -1916,6 +1916,8 @@ enum pci_fixup_pass {
> >>>  	pci_fixup_suspend_late,	/* pci_device_suspend_late() */
> >>>  };
> >>>  
> >>> +void pci_quirk_broken_parity(struct pci_dev *dev);
> >>> +
> >>>  #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
> >>>  #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class,	\
> >>>  				    class_shift, hook)			\
> >>> -- 
> >>> 2.30.0
> >>>
> >>>
> >>>
> >