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

Shuai Xue
2026-01-28T12:30:14Z

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