Re: [PATCH v7 3/5] PCI/AER: Report fatal errors of RCiEP and EP if link recoverd

[Shuai Xue <xueshuai@linux.alibaba.com>]

On 1/27/26 6:36 PM, Jonathan Cameron wrote:
> On Sat, 24 Jan 2026 15:45:55 +0800
> Shuai Xue <xueshuai@linux.alibaba.com> wrote:
> 
>> The AER driver has historically avoided reading the configuration space of
>> an endpoint or RCiEP that reported a fatal error, considering the link to
>> that device unreliable. Consequently, when a fatal error occurs, the AER
>> and DPC drivers do not report specific error types, resulting in logs like:
>>
>>    pcieport 0015:00:00.0: EDR: EDR event received
>>    pcieport 0015:00:00.0: EDR: Reported EDR dev: 0015:00:00.0
>>    pcieport 0015:00:00.0: DPC: containment event, status:0x200d, ERR_FATAL received from 0015:01:00.0
>>    pcieport 0015:00:00.0: AER: broadcast error_detected message
>>    pcieport 0015:00:00.0: AER: broadcast mmio_enabled message
>>    pcieport 0015:00:00.0: AER: broadcast resume message
>>    pcieport 0015:00:00.0: pciehp: Slot(21): Link Down/Up ignored
>>    pcieport 0015:00:00.0: AER: device recovery successful
>>    pcieport 0015:00:00.0: EDR: DPC port successfully recovered
>>    pcieport 0015:00:00.0: EDR: Status for 0015:00:00.0: 0x80
>>
>> AER status registers are sticky and Write-1-to-clear. If the link recovered
>> after hot reset, we can still safely access AER status and TLP header of the
>> error device. In such case, report fatal errors which helps to figure out the
>> error root case.
>>
>> After this patch, the logs like:
>>
>>    pcieport 0015:00:00.0: EDR: EDR event received
>>    pcieport 0015:00:00.0: EDR: Reported EDR dev: 0015:00:00.0
>>    pcieport 0015:00:00.0: DPC: containment event, status:0x200d, ERR_FATAL received from 0015:01:00.0
>>    pcieport 0015:00:00.0: AER: broadcast error_detected message
>> + vfio-pci 0015:01:00.0: AER: Errors reported prior to reset
>> + vfio-pci 0015:01:00.0: PCIe Bus Error: severity=Uncorrectable (Fatal), type=Transaction Layer, (Receiver ID)
>> + vfio-pci 0015:01:00.0:   device [144d:a80a] error status/mask=00001000/00400000
>> + vfio-pci 0015:01:00.0:    [12] TLP                    (First)
>> + vfio-pci 0015:01:00.0: AER:   TLP Header: 0x4a004010 0x00000040 0x01000000 0xffffffff
>>    pcieport 0015:00:00.0: AER: broadcast mmio_enabled message
>>    pcieport 0015:00:00.0: AER: broadcast resume message
>>    pcieport 0015:00:00.0: pciehp: Slot(21): Link Down/Up ignored
>>    pcieport 0015:00:00.0: AER: device recovery successful
>>    pcieport 0015:00:00.0: EDR: DPC port successfully recovered
>>    pcieport 0015:00:00.0: EDR: Status for 0015:00:00.0: 0x80
>>
>> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
> Hi Shuai,
> 
> With the structure zeroed below (just to make this easier to review, not because
> there is a bug as far as I can see)
> Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
> 
>> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
>> index e0bcaa896803..4c0a2bbe9197 100644
>> --- a/drivers/pci/pcie/aer.c
>> +++ b/drivers/pci/pcie/aer.c
> 
>> @@ -1447,17 +1450,38 @@ int aer_get_device_error_info(struct aer_err_info *info, int i)
>>   	return 1;
>>   }
>>   
>> +void aer_report_frozen_error(struct pci_dev *dev)
>> +{
>> +	struct aer_err_info info;
>> +	int type = pci_pcie_type(dev);
>> +
>> +	if (type != PCI_EXP_TYPE_ENDPOINT && type != PCI_EXP_TYPE_RC_END)
>> +		return;
>> +
> 
> struct aer_err_info has a bunch of fields. I'd just make sure it's zeroed
> to avoid us having to check that they are all filled in. = {};
> or do it with the initial values being assigned.
> 
> 	info = (struct aer_err_info) {
> 		.err_dev_num = 0,
> 		.severity = AER_FATAL,
> 		.level = KERN_ERR,
> 	};
> 	add_error_device(&info, dev);
> 
> 

Got it. Will fix it in next verison.

Thanks for valuable comments.

Best Regards,
Shuai