Correctable errors do not need any software intervention, so
avoid calling into the software recovery process for correctable
errors.
Signed-off-by: Tyler Baicar <[email protected]>
---
drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
index b1303b3..4765c11 100644
--- a/drivers/pci/pcie/aer/aerdrv_core.c
+++ b/drivers/pci/pcie/aer/aerdrv_core.c
@@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
continue;
}
cper_print_aer(pdev, entry.severity, entry.regs);
- do_recovery(pdev, entry.severity);
+ if (entry.severity != AER_CORRECTABLE)
+ do_recovery(pdev, entry.severity);
pci_dev_put(pdev);
}
}
--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.
On Wed, Nov 15, 2017 at 09:46:42AM -0500, Tyler Baicar wrote:
> On 10/2/2017 7:19 PM, Bjorn Helgaas wrote:
> >On Mon, Aug 28, 2017 at 11:09:44AM -0600, Tyler Baicar wrote:
> >>Correctable errors do not need any software intervention, so
> >>avoid calling into the software recovery process for correctable
> >>errors.
> >>
> >>Signed-off-by: Tyler Baicar <[email protected]>
> >>---
> >> drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
> >> 1 file changed, 2 insertions(+), 1 deletion(-)
> >>
> >>diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
> >>index b1303b3..4765c11 100644
> >>--- a/drivers/pci/pcie/aer/aerdrv_core.c
> >>+++ b/drivers/pci/pcie/aer/aerdrv_core.c
> >>@@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
> >> continue;
> >> }
> >> cper_print_aer(pdev, entry.severity, entry.regs);
> >>- do_recovery(pdev, entry.severity);
> >>+ if (entry.severity != AER_CORRECTABLE)
> >>+ do_recovery(pdev, entry.severity);
> >I think this is fine, and it mirrors what is done in
> >handle_error_source().
> >
> Hello,
>
> Will this patch be pulled into 4.15?
Sorry, I didn't get to this in time for v4.15, but I put it on pci/aer
for v4.16. I expanded the changelog to note that this means we won't
call the driver's callbacks or emit the "recovery successful" message
for correctable errors from APEI, and that this matches what we
already do for the non-APEI path.
Bjorn
commit 72761170e6d5519c91136fd6cc80805a74ef9cfd
Author: Tyler Baicar <[email protected]>
Date: Mon Aug 28 11:09:44 2017 -0600
PCI/AER: Skip recovery callbacks for correctable errors from ACPI APEI
PCIe correctable errors are corrected by hardware. Software may log them,
but no other software intervention is required.
There are two paths to enter the AER recovery code: (1) the native path
where Linux fields the AER interrupt and reads the AER registers directly,
and (2) the ACPI path where firmware reads the AER registers and hands them
off to Linux via the ACPI APEI path.
The AER do_recovery() function calls driver error reporting callbacks
(error_detected(), mmio_enabled(), resume(), etc), attempts recovery (for
fatal errors), and logs a "AER: Device recovery successful" message.
Since there's nothing to recover for correctable errors, the native path
already skips do_recovery(), so it doesn't call the driver callbacks and or
emit the message. Make the APEI path do the same.
Signed-off-by: Tyler Baicar <[email protected]>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <[email protected]>
diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
index 744805232155..3e354f224422 100644
--- a/drivers/pci/pcie/aer/aerdrv_core.c
+++ b/drivers/pci/pcie/aer/aerdrv_core.c
@@ -633,7 +633,8 @@ static void aer_recover_work_func(struct work_struct *work)
continue;
}
cper_print_aer(pdev, entry.severity, entry.regs);
- do_recovery(pdev, entry.severity);
+ if (entry.severity != AER_CORRECTABLE)
+ do_recovery(pdev, entry.severity);
pci_dev_put(pdev);
}
}
From 1584143803622234034@xxx Wed Nov 15 14:47:39 +0000 2017
X-GM-THRID: 1576995657442027352
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread
On 10/2/2017 7:19 PM, Bjorn Helgaas wrote:
> On Mon, Aug 28, 2017 at 11:09:44AM -0600, Tyler Baicar wrote:
>> Correctable errors do not need any software intervention, so
>> avoid calling into the software recovery process for correctable
>> errors.
>>
>> Signed-off-by: Tyler Baicar <[email protected]>
>> ---
>> drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
>> index b1303b3..4765c11 100644
>> --- a/drivers/pci/pcie/aer/aerdrv_core.c
>> +++ b/drivers/pci/pcie/aer/aerdrv_core.c
>> @@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
>> continue;
>> }
>> cper_print_aer(pdev, entry.severity, entry.regs);
>> - do_recovery(pdev, entry.severity);
>> + if (entry.severity != AER_CORRECTABLE)
>> + do_recovery(pdev, entry.severity);
> I think this is fine, and it mirrors what is done in
> handle_error_source().
>
Hello,
Will this patch be pulled into 4.15?
Thanks,
Tyler
--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.
From 1583466412996301871@xxx Wed Nov 08 03:20:48 +0000 2017
X-GM-THRID: 1576995657442027352
X-Gmail-Labels: Inbox,Category Forums,HistoricalUnread
On 10/11/2017 1:09 PM, Bjorn Helgaas wrote:
> On Wed, Oct 11, 2017 at 10:37:47AM -0400, Tyler Baicar wrote:
>> On 10/2/2017 7:19 PM, Bjorn Helgaas wrote:
>>> On Mon, Aug 28, 2017 at 11:09:44AM -0600, Tyler Baicar wrote:
>>>> Correctable errors do not need any software intervention, so
>>>> avoid calling into the software recovery process for correctable
>>>> errors.
>>>>
>>>> Signed-off-by: Tyler Baicar <[email protected]>
>>>> ---
>>>> drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
>>>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
>>>> index b1303b3..4765c11 100644
>>>> --- a/drivers/pci/pcie/aer/aerdrv_core.c
>>>> +++ b/drivers/pci/pcie/aer/aerdrv_core.c
>>>> @@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
>>>> continue;
>>>> }
>>>> cper_print_aer(pdev, entry.severity, entry.regs);
>>>> - do_recovery(pdev, entry.severity);
>>>> + if (entry.severity != AER_CORRECTABLE)
>>>> + do_recovery(pdev, entry.severity);
>>> I think this is fine, and it mirrors what is done in
>>> handle_error_source().
>>>
>>> But I want to converge the APEI path and the "native" AER path, so as
>>> one tiny step in that direction, can you look into doing this test
>>> once, e.g., move the test from handle_error_source() into
>>> do_recovery(), where one test will handle both paths?
>> I've looked into this and it seems there is still going to need to
>> be two versions of this check. The native AER path goes through
>> handle_error_source() and for correctable errors requires the write
>> to PCI_ERR_COR_STATUS, but the APEI path does not require this
>> write. I could move this check to the beginning of do_recovery() so
>> it returns right away for correctable errors and remove the else
>> line in handle_error_source() so it always calls into do_recovery().
>> That doesn't seem like a very clean solution though since then there
>> are still two checks for correctable errors and now we're calling
>> into do_recovery() in both cases for nothing :)
> The PCI_ERR_COR_STATUS thing is part of what I see as the problem
> here. IMHO, the native AER path should collect up the log registers
> (and do any acknowledgement, e.g., writing PCI_ERR_COR_STATUS)
> *before* entering the common path.
>
> In other words, the Linux code in the native part of AER should be
> functionally the same as the BIOS code that implements the APEI path.
>
> This is a bit of restructuring in the Linux AER code. I haven't
> looked enough to know how much. If it's impractical, it's
> impractical. I thought this might be an opportunity for a tiny step
> in that direction, but if it's not, I guess that's OK.
Hello Bjorn,
That restructuring doesn't look trivial to do in this patch, so do you think
this patch is
good for 4.15?
Thanks,
Tyler
--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.
From 1580981930276887857@xxx Wed Oct 11 17:11:01 +0000 2017
X-GM-THRID: 1576995657442027352
X-Gmail-Labels: Inbox,Category Forums
On Wed, Oct 11, 2017 at 10:37:47AM -0400, Tyler Baicar wrote:
> On 10/2/2017 7:19 PM, Bjorn Helgaas wrote:
> >On Mon, Aug 28, 2017 at 11:09:44AM -0600, Tyler Baicar wrote:
> >>Correctable errors do not need any software intervention, so
> >>avoid calling into the software recovery process for correctable
> >>errors.
> >>
> >>Signed-off-by: Tyler Baicar <[email protected]>
> >>---
> >> drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
> >> 1 file changed, 2 insertions(+), 1 deletion(-)
> >>
> >>diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
> >>index b1303b3..4765c11 100644
> >>--- a/drivers/pci/pcie/aer/aerdrv_core.c
> >>+++ b/drivers/pci/pcie/aer/aerdrv_core.c
> >>@@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
> >> continue;
> >> }
> >> cper_print_aer(pdev, entry.severity, entry.regs);
> >>- do_recovery(pdev, entry.severity);
> >>+ if (entry.severity != AER_CORRECTABLE)
> >>+ do_recovery(pdev, entry.severity);
> >I think this is fine, and it mirrors what is done in
> >handle_error_source().
> >
> >But I want to converge the APEI path and the "native" AER path, so as
> >one tiny step in that direction, can you look into doing this test
> >once, e.g., move the test from handle_error_source() into
> >do_recovery(), where one test will handle both paths?
>
> I've looked into this and it seems there is still going to need to
> be two versions of this check. The native AER path goes through
> handle_error_source() and for correctable errors requires the write
> to PCI_ERR_COR_STATUS, but the APEI path does not require this
> write. I could move this check to the beginning of do_recovery() so
> it returns right away for correctable errors and remove the else
> line in handle_error_source() so it always calls into do_recovery().
> That doesn't seem like a very clean solution though since then there
> are still two checks for correctable errors and now we're calling
> into do_recovery() in both cases for nothing :)
The PCI_ERR_COR_STATUS thing is part of what I see as the problem
here. IMHO, the native AER path should collect up the log registers
(and do any acknowledgement, e.g., writing PCI_ERR_COR_STATUS)
*before* entering the common path.
In other words, the Linux code in the native part of AER should be
functionally the same as the BIOS code that implements the APEI path.
This is a bit of restructuring in the Linux AER code. I haven't
looked enough to know how much. If it's impractical, it's
impractical. I thought this might be an opportunity for a tiny step
in that direction, but if it's not, I guess that's OK.
Bjorn
From 1580972415148155031@xxx Wed Oct 11 14:39:47 +0000 2017
X-GM-THRID: 1576995657442027352
X-Gmail-Labels: Inbox,Category Forums
On 10/2/2017 7:19 PM, Bjorn Helgaas wrote:
> On Mon, Aug 28, 2017 at 11:09:44AM -0600, Tyler Baicar wrote:
>> Correctable errors do not need any software intervention, so
>> avoid calling into the software recovery process for correctable
>> errors.
>>
>> Signed-off-by: Tyler Baicar <[email protected]>
>> ---
>> drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
>> index b1303b3..4765c11 100644
>> --- a/drivers/pci/pcie/aer/aerdrv_core.c
>> +++ b/drivers/pci/pcie/aer/aerdrv_core.c
>> @@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
>> continue;
>> }
>> cper_print_aer(pdev, entry.severity, entry.regs);
>> - do_recovery(pdev, entry.severity);
>> + if (entry.severity != AER_CORRECTABLE)
>> + do_recovery(pdev, entry.severity);
> I think this is fine, and it mirrors what is done in
> handle_error_source().
>
> But I want to converge the APEI path and the "native" AER path, so as
> one tiny step in that direction, can you look into doing this test
> once, e.g., move the test from handle_error_source() into
> do_recovery(), where one test will handle both paths?
Hello Bjorn,
Thank you for the input!
I've looked into this and it seems there is still going to need to be
two versions of this check. The native AER path goes through
handle_error_source() and for correctable errors requires the write to
PCI_ERR_COR_STATUS, but the APEI path does not require this write. I
could move this check to the beginning of do_recovery() so it returns
right away for correctable errors and remove the else line in
handle_error_source() so it always calls into do_recovery(). That
doesn't seem like a very clean solution though since then there are
still two checks for correctable errors and now we're calling into
do_recovery() in both cases for nothing :)
Thanks,
Tyler
From 1580189754897847351@xxx Mon Oct 02 23:19:44 +0000 2017
X-GM-THRID: 1576995657442027352
X-Gmail-Labels: Inbox,Category Forums
On Mon, Aug 28, 2017 at 11:09:44AM -0600, Tyler Baicar wrote:
> Correctable errors do not need any software intervention, so
> avoid calling into the software recovery process for correctable
> errors.
>
> Signed-off-by: Tyler Baicar <[email protected]>
> ---
> drivers/pci/pcie/aer/aerdrv_core.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c
> index b1303b3..4765c11 100644
> --- a/drivers/pci/pcie/aer/aerdrv_core.c
> +++ b/drivers/pci/pcie/aer/aerdrv_core.c
> @@ -626,7 +626,8 @@ static void aer_recover_work_func(struct work_struct *work)
> continue;
> }
> cper_print_aer(pdev, entry.severity, entry.regs);
> - do_recovery(pdev, entry.severity);
> + if (entry.severity != AER_CORRECTABLE)
> + do_recovery(pdev, entry.severity);
I think this is fine, and it mirrors what is done in
handle_error_source().
But I want to converge the APEI path and the "native" AER path, so as
one tiny step in that direction, can you look into doing this test
once, e.g., move the test from handle_error_source() into
do_recovery(), where one test will handle both paths?
> pci_dev_put(pdev);
> }
> }
> --
> Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
> Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project.
>
From 1576995657442027352@xxx Mon Aug 28 17:10:55 +0000 2017
X-GM-THRID: 1576995657442027352
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