On errors reported from CPER, cper_print_bits() was used to log the
AER bits. This resulted in hard-to-understand messages, without a
prefix. Instead use __aer_print_error() for both native AER and CPER
to provide a more consistent log format.
Signed-off-by: Alexandru Gagniuc <[email protected]>
---
drivers/pci/pcie/aer/aerdrv_errprint.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
index cfc89dd57831..cfae4d52f848 100644
--- a/drivers/pci/pcie/aer/aerdrv_errprint.c
+++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
@@ -216,28 +216,30 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
void cper_print_aer(struct pci_dev *dev, int aer_severity,
struct aer_capability_regs *aer)
{
- int layer, agent, status_strs_size, tlp_header_valid = 0;
+ int layer, agent, tlp_header_valid = 0;
u32 status, mask;
- const char **status_strs;
+ struct aer_err_info info;
if (aer_severity == AER_CORRECTABLE) {
status = aer->cor_status;
mask = aer->cor_mask;
- status_strs = aer_correctable_error_string;
- status_strs_size = ARRAY_SIZE(aer_correctable_error_string);
} else {
status = aer->uncor_status;
mask = aer->uncor_mask;
- status_strs = aer_uncorrectable_error_string;
- status_strs_size = ARRAY_SIZE(aer_uncorrectable_error_string);
tlp_header_valid = status & AER_LOG_TLP_MASKS;
}
layer = AER_GET_LAYER_ERROR(aer_severity, status);
agent = AER_GET_AGENT(aer_severity, status);
+ memset(&info, 0, sizeof(info));
+ info.severity = aer_severity;
+ info.status = status;
+ info.mask = mask;
+ info.first_error = 0x1f;
+
pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
- cper_print_bits("", status, status_strs, status_strs_size);
+ __aer_print_error(dev, &info);
pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
aer_error_layer[layer], aer_agent_string[agent]);
--
2.14.3
On 4/17/2018 1:09 PM, Alexandru Gagniuc wrote:
> On errors reported from CPER, cper_print_bits() was used to log the
> AER bits. This resulted in hard-to-understand messages, without a
> prefix. Instead use __aer_print_error() for both native AER and CPER
> to provide a more consistent log format.
>
> Signed-off-by: Alexandru Gagniuc <[email protected]>
Tested-by: Tyler Baicar <[email protected]>
Thanks!
> ---
> drivers/pci/pcie/aer/aerdrv_errprint.c | 16 +++++++++-------
> 1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
> index cfc89dd57831..cfae4d52f848 100644
> --- a/drivers/pci/pcie/aer/aerdrv_errprint.c
> +++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
> @@ -216,28 +216,30 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
> void cper_print_aer(struct pci_dev *dev, int aer_severity,
> struct aer_capability_regs *aer)
> {
> - int layer, agent, status_strs_size, tlp_header_valid = 0;
> + int layer, agent, tlp_header_valid = 0;
> u32 status, mask;
> - const char **status_strs;
> + struct aer_err_info info;
>
> if (aer_severity == AER_CORRECTABLE) {
> status = aer->cor_status;
> mask = aer->cor_mask;
> - status_strs = aer_correctable_error_string;
> - status_strs_size = ARRAY_SIZE(aer_correctable_error_string);
> } else {
> status = aer->uncor_status;
> mask = aer->uncor_mask;
> - status_strs = aer_uncorrectable_error_string;
> - status_strs_size = ARRAY_SIZE(aer_uncorrectable_error_string);
> tlp_header_valid = status & AER_LOG_TLP_MASKS;
> }
>
> layer = AER_GET_LAYER_ERROR(aer_severity, status);
> agent = AER_GET_AGENT(aer_severity, status);
>
> + memset(&info, 0, sizeof(info));
> + info.severity = aer_severity;
> + info.status = status;
> + info.mask = mask;
> + info.first_error = 0x1f;
> +
> pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
> - cper_print_bits("", status, status_strs, status_strs_size);
> + __aer_print_error(dev, &info);
> pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
> aer_error_layer[layer], aer_agent_string[agent]);
>
--
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 Tue, Apr 17, 2018 at 12:09:43PM -0500, Alexandru Gagniuc wrote:
> On errors reported from CPER, cper_print_bits() was used to log the
> AER bits. This resulted in hard-to-understand messages, without a
> prefix. Instead use __aer_print_error() for both native AER and CPER
> to provide a more consistent log format.
>
> Signed-off-by: Alexandru Gagniuc <[email protected]>
> ---
> drivers/pci/pcie/aer/aerdrv_errprint.c | 16 +++++++++-------
> 1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
> index cfc89dd57831..cfae4d52f848 100644
> --- a/drivers/pci/pcie/aer/aerdrv_errprint.c
> +++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
> @@ -216,28 +216,30 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
> void cper_print_aer(struct pci_dev *dev, int aer_severity,
> struct aer_capability_regs *aer)
> {
> - int layer, agent, status_strs_size, tlp_header_valid = 0;
> + int layer, agent, tlp_header_valid = 0;
> u32 status, mask;
> - const char **status_strs;
> + struct aer_err_info info;
>
> if (aer_severity == AER_CORRECTABLE) {
> status = aer->cor_status;
> mask = aer->cor_mask;
> - status_strs = aer_correctable_error_string;
> - status_strs_size = ARRAY_SIZE(aer_correctable_error_string);
> } else {
> status = aer->uncor_status;
> mask = aer->uncor_mask;
> - status_strs = aer_uncorrectable_error_string;
> - status_strs_size = ARRAY_SIZE(aer_uncorrectable_error_string);
> tlp_header_valid = status & AER_LOG_TLP_MASKS;
> }
>
> layer = AER_GET_LAYER_ERROR(aer_severity, status);
> agent = AER_GET_AGENT(aer_severity, status);
>
> + memset(&info, 0, sizeof(info));
> + info.severity = aer_severity;
> + info.status = status;
> + info.mask = mask;
> + info.first_error = 0x1f;
I like this patch a lot, but where does this "first_error = 0x1f" come
from?
I assume this is supposed to be the "First Error Pointer" in the
Advanced Error Capabilities and Control register (PCIe r4.0, sec
7.8.4.7). There is a "cap_control" field in struct
aer_capability_regs; should we be using that here?
> +
> pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
> - cper_print_bits("", status, status_strs, status_strs_size);
> + __aer_print_error(dev, &info);
> pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
> aer_error_layer[layer], aer_agent_string[agent]);
>
> --
> 2.14.3
>
On 04/27/2018 05:43 PM, Bjorn Helgaas wrote:
> On Tue, Apr 17, 2018 at 12:09:43PM -0500, Alexandru Gagniuc wrote:
>> On errors reported from CPER, cper_print_bits() was used to log the
>> AER bits. This resulted in hard-to-understand messages, without a
>> prefix. Instead use __aer_print_error() for both native AER and CPER
>> to provide a more consistent log format.
>>
>> Signed-off-by: Alexandru Gagniuc <[email protected]>
>> ---
>> drivers/pci/pcie/aer/aerdrv_errprint.c | 16 +++++++++-------
>> 1 file changed, 9 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
>> index cfc89dd57831..cfae4d52f848 100644
>> --- a/drivers/pci/pcie/aer/aerdrv_errprint.c
>> +++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
>> @@ -216,28 +216,30 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
>> void cper_print_aer(struct pci_dev *dev, int aer_severity,
>> struct aer_capability_regs *aer)
>> {
>> - int layer, agent, status_strs_size, tlp_header_valid = 0;
>> + int layer, agent, tlp_header_valid = 0;
>> u32 status, mask;
>> - const char **status_strs;
>> + struct aer_err_info info;
>>
>> if (aer_severity == AER_CORRECTABLE) {
>> status = aer->cor_status;
>> mask = aer->cor_mask;
>> - status_strs = aer_correctable_error_string;
>> - status_strs_size = ARRAY_SIZE(aer_correctable_error_string);
>> } else {
>> status = aer->uncor_status;
>> mask = aer->uncor_mask;
>> - status_strs = aer_uncorrectable_error_string;
>> - status_strs_size = ARRAY_SIZE(aer_uncorrectable_error_string);
>> tlp_header_valid = status & AER_LOG_TLP_MASKS;
>> }
>>
>> layer = AER_GET_LAYER_ERROR(aer_severity, status);
>> agent = AER_GET_AGENT(aer_severity, status);
>>
>> + memset(&info, 0, sizeof(info));
>> + info.severity = aer_severity;
>> + info.status = status;
>> + info.mask = mask;
>> + info.first_error = 0x1f;
>
> I like this patch a lot, but where does this "first_error = 0x1f" come
> from?
aer_(un)correctable_error_string don't go to [0x1f], so this guarantees
us we don't print "(First)".
> I assume this is supposed to be the "First Error Pointer" in the
> Advanced Error Capabilities and Control register (PCIe r4.0, sec
> 7.8.4.7). There is a "cap_control" field in struct
> aer_capability_regs; should we be using that here?
There is a way to extract it from the PCI regs, and it's quite simple.
IIRC, it should be all f's when the capability is not implemented. I
wanted to avoid any further parsing of PCI regs in this patch.
I can see a way to use even more common printk code, but that requires
validating the PCI regs we get from firmware. That means we need to make
a guarantee about CPER that is beyond the scope of this patch.
Alex
>> +
>> pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
>> - cper_print_bits("", status, status_strs, status_strs_size);
>> + __aer_print_error(dev, &info);
>> pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
>> aer_error_layer[layer], aer_agent_string[agent]);
>>
>> --
>> 2.14.3
>>
On 04/28/2018 11:46 AM, Alex G. wrote:
> On 04/27/2018 05:43 PM, Bjorn Helgaas wrote:
>> On Tue, Apr 17, 2018 at 12:09:43PM -0500, Alexandru Gagniuc wrote:
(snip)
>>> + memset(&info, 0, sizeof(info));
>>> + info.severity = aer_severity;
>>> + info.status = status;
>>> + info.mask = mask;
>>> + info.first_error = 0x1f;
>>
>> I like this patch a lot, but where does this "first_error = 0x1f" come
>> from?
>
> aer_(un)correctable_error_string don't go to [0x1f], so this guarantees
> us we don't print "(First)".
>
>> I assume this is supposed to be the "First Error Pointer" in the
>> Advanced Error Capabilities and Control register (PCIe r4.0, sec
>> 7.8.4.7). There is a "cap_control" field in struct
>> aer_capability_regs; should we be using that here?
>
> There is a way to extract it from the PCI regs, and it's quite simple.
> IIRC, it should be all f's when the capability is not implemented. I
> wanted to avoid any further parsing of PCI regs in this patch.
I could update the offending line to say:
+ info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
Though I still have the concerns with validating CPER data:
> I can see a way to use even more common printk code, but that requires
> validating the PCI regs we get from firmware. That means we need to make
> a guarantee about CPER that is beyond the scope of this patch.
>
> Alex
>
On Sat, Apr 28, 2018 at 12:07:48PM -0500, Alex G. wrote:
> On 04/28/2018 11:46 AM, Alex G. wrote:
> > On 04/27/2018 05:43 PM, Bjorn Helgaas wrote:
> > > On Tue, Apr 17, 2018 at 12:09:43PM -0500, Alexandru Gagniuc wrote:
> (snip)
> > > > +??? memset(&info, 0, sizeof(info));
> > > > +??? info.severity = aer_severity;
> > > > +??? info.status = status;
> > > > +??? info.mask = mask;
> > > > +??? info.first_error = 0x1f;
> > >
> > > I like this patch a lot, but where does this "first_error = 0x1f" come
> > > from?
> >
> > aer_(un)correctable_error_string don't go to [0x1f], so this guarantees
> > us we don't print "(First)".
> >
> > > I assume this is supposed to be the "First Error Pointer" in the
> > > Advanced Error Capabilities and Control register (PCIe r4.0, sec
> > > 7.8.4.7).? There is a "cap_control" field in struct
> > > aer_capability_regs; should we be using that here?
> >
> > There is a way to extract it from the PCI regs, and it's quite simple.
> > IIRC, it should be all f's when the capability is not implemented. I
> > wanted to avoid any further parsing of PCI regs in this patch.
>
> I could update the offending line to say:
> + info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
That's what I would have expected. So I'd say either do this, or add
a comment about why it's not the right thing to do.
> Though I still have the concerns with validating CPER data:
>
> > I can see a way to use even more common printk code, but that requires
> > validating the PCI regs we get from firmware. That means we need to make
> > a guarantee about CPER that is beyond the scope of this patch.
Sounds like this is material for another patch, but if/when you do
that, I'd like to understand your concern about validating the
registers we get from firmware. Are you worried about getting
incorrect register contents, then printing the wrong info, making
the wrong decision about how to recover, something else?
Bjorn
On 04/30/2018 12:15 PM, Bjorn Helgaas wrote:
> On Sat, Apr 28, 2018 at 12:07:48PM -0500, Alex G. wrote:
(snip)
>> I could update the offending line to say:
>> + info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
>
> That's what I would have expected. So I'd say either do this, or add
> a comment about why it's not the right thing to do.
Okay.
>> Though I still have the concerns with validating CPER data:
>>
>>> I can see a way to use even more common printk code, but that requires
>>> validating the PCI regs we get from firmware. That means we need to make
>>> a guarantee about CPER that is beyond the scope of this patch.
>
> Sounds like this is material for another patch, but if/when you do
> that, I'd like to understand your concern about validating the
> registers we get from firmware. Are you worried about getting
> incorrect register contents, then printing the wrong info, making
> the wrong decision about how to recover, something else?
I don't trust firmware, and I have daymares about firmware leaving these
fields uninitialized. In jargon, I'd like to treat it as external
untrusted serialized data.
Alex
On errors reported from CPER, cper_print_bits() was used to log the
AER bits. This resulted in hard-to-understand messages, without a
prefix. Instead use __aer_print_error() for both native AER and CPER
to provide a more consistent log format.
Signed-off-by: Alexandru Gagniuc <[email protected]>
---
Changes since v1:
- Parse aer regs for first error pointer instead of disabling it
On the Dell machine where I tested this, the first error pointer is
reported correctly by firmware.
drivers/pci/pcie/aer/aerdrv_errprint.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
index cfc89dd57831..b5612cc51b63 100644
--- a/drivers/pci/pcie/aer/aerdrv_errprint.c
+++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
@@ -216,28 +216,30 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
void cper_print_aer(struct pci_dev *dev, int aer_severity,
struct aer_capability_regs *aer)
{
- int layer, agent, status_strs_size, tlp_header_valid = 0;
+ int layer, agent, tlp_header_valid = 0;
u32 status, mask;
- const char **status_strs;
+ struct aer_err_info info;
if (aer_severity == AER_CORRECTABLE) {
status = aer->cor_status;
mask = aer->cor_mask;
- status_strs = aer_correctable_error_string;
- status_strs_size = ARRAY_SIZE(aer_correctable_error_string);
} else {
status = aer->uncor_status;
mask = aer->uncor_mask;
- status_strs = aer_uncorrectable_error_string;
- status_strs_size = ARRAY_SIZE(aer_uncorrectable_error_string);
tlp_header_valid = status & AER_LOG_TLP_MASKS;
}
layer = AER_GET_LAYER_ERROR(aer_severity, status);
agent = AER_GET_AGENT(aer_severity, status);
+ memset(&info, 0, sizeof(info));
+ info.severity = aer_severity;
+ info.status = status;
+ info.mask = mask;
+ info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
+
pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
- cper_print_bits("", status, status_strs, status_strs_size);
+ __aer_print_error(dev, &info);
pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
aer_error_layer[layer], aer_agent_string[agent]);
--
2.14.3
On Mon, Apr 30, 2018 at 12:41:26PM -0500, Alex G. wrote:
> On 04/30/2018 12:15 PM, Bjorn Helgaas wrote:
> > On Sat, Apr 28, 2018 at 12:07:48PM -0500, Alex G. wrote:
>
> (snip)
> >> I could update the offending line to say:
> >> + info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
> >
> > That's what I would have expected. So I'd say either do this, or add
> > a comment about why it's not the right thing to do.
>
> Okay.
>
> >> Though I still have the concerns with validating CPER data:
> >>
> >>> I can see a way to use even more common printk code, but that requires
> >>> validating the PCI regs we get from firmware. That means we need to make
> >>> a guarantee about CPER that is beyond the scope of this patch.
> >
> > Sounds like this is material for another patch, but if/when you do
> > that, I'd like to understand your concern about validating the
> > registers we get from firmware. Are you worried about getting
> > incorrect register contents, then printing the wrong info, making
> > the wrong decision about how to recover, something else?
>
> I don't trust firmware, and I have daymares about firmware leaving these
> fields uninitialized. In jargon, I'd like to treat it as external
> untrusted serialized data.
That makes good sense to me.
In this particular case, we only test first_error for equality:
__aer_print_error(...)
{
...
pci_err(dev, " [%2d] %-22s%s\n", i, errmsg,
info->first_error == i ? " (First)" : "");
so I don't think there's any danger. If we were using it to index an
array or something, we should certainly validate it first.
On Mon, Apr 30, 2018 at 02:52:15PM -0500, Alexandru Gagniuc wrote:
> On errors reported from CPER, cper_print_bits() was used to log the
> AER bits. This resulted in hard-to-understand messages, without a
> prefix. Instead use __aer_print_error() for both native AER and CPER
> to provide a more consistent log format.
>
> Signed-off-by: Alexandru Gagniuc <[email protected]>
Applied to pci/aer for v4.18, thanks!
> ---
>
> Changes since v1:
> - Parse aer regs for first error pointer instead of disabling it
> On the Dell machine where I tested this, the first error pointer is
> reported correctly by firmware.
>
> drivers/pci/pcie/aer/aerdrv_errprint.c | 16 +++++++++-------
> 1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
> index cfc89dd57831..b5612cc51b63 100644
> --- a/drivers/pci/pcie/aer/aerdrv_errprint.c
> +++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
> @@ -216,28 +216,30 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
> void cper_print_aer(struct pci_dev *dev, int aer_severity,
> struct aer_capability_regs *aer)
> {
> - int layer, agent, status_strs_size, tlp_header_valid = 0;
> + int layer, agent, tlp_header_valid = 0;
> u32 status, mask;
> - const char **status_strs;
> + struct aer_err_info info;
>
> if (aer_severity == AER_CORRECTABLE) {
> status = aer->cor_status;
> mask = aer->cor_mask;
> - status_strs = aer_correctable_error_string;
> - status_strs_size = ARRAY_SIZE(aer_correctable_error_string);
> } else {
> status = aer->uncor_status;
> mask = aer->uncor_mask;
> - status_strs = aer_uncorrectable_error_string;
> - status_strs_size = ARRAY_SIZE(aer_uncorrectable_error_string);
> tlp_header_valid = status & AER_LOG_TLP_MASKS;
> }
>
> layer = AER_GET_LAYER_ERROR(aer_severity, status);
> agent = AER_GET_AGENT(aer_severity, status);
>
> + memset(&info, 0, sizeof(info));
> + info.severity = aer_severity;
> + info.status = status;
> + info.mask = mask;
> + info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
> +
> pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
> - cper_print_bits("", status, status_strs, status_strs_size);
> + __aer_print_error(dev, &info);
> pci_err(dev, "aer_layer=%s, aer_agent=%s\n",
> aer_error_layer[layer], aer_agent_string[agent]);
>
> --
> 2.14.3
>