在 2024/11/7 00:02, Bjorn Helgaas 写道:
On Wed, Nov 06, 2024 at 05:03:39PM +0800, Shuai Xue 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:
[ 245.281980] pcieport 0000:30:03.0: EDR: EDR event received
[ 245.287466] pcieport 0000:30:03.0: DPC: containment event, status:0x0005 source:0x3400
[ 245.295372] pcieport 0000:30:03.0: DPC: ERR_FATAL detected
[ 245.300849] pcieport 0000:30:03.0: AER: broadcast error_detected message
[ 245.307540] nvme nvme0: frozen state error detected, reset controller
[ 245.722582] nvme 0000:34:00.0: ready 0ms after DPC
[ 245.727365] pcieport 0000:30:03.0: AER: broadcast slot_reset message
But, if the link recovered after hot reset, we can safely access AER status of
the error device. In such case, report fatal error which helps to figure out the
error root case.
Explain why we can access these registers after reset. I think it's
important that these registers are sticky ("RW1CS" per spec).
Yes, AER error status registers are Sticky and Write-1-to-clear. If we
does not read them after reset_subordinates, the registers will be
cleared in pci_error_handlers, e.g. nvme_err_handler
slot_reset() => nvme_slot_reset()
pci_restore_state()
pci_aer_clear_status()
Will add the reason in commit log.
After this patch, the logs like:
[ 414.356755] pcieport 0000:30:03.0: EDR: EDR event received
[ 414.362240] pcieport 0000:30:03.0: DPC: containment event, status:0x0005 source:0x3400
[ 414.370148] pcieport 0000:30:03.0: DPC: ERR_FATAL detected
[ 414.375642] pcieport 0000:30:03.0: AER: broadcast error_detected message
[ 414.382335] nvme nvme0: frozen state error detected, reset controller
[ 414.645413] pcieport 0000:30:03.0: waiting 100 ms for downstream link, after activation
[ 414.788016] nvme 0000:34:00.0: ready 0ms after DPC
[ 414.796975] nvme 0000:34:00.0: PCIe Bus Error: severity=Uncorrectable (Fatal), type=Data Link Layer, (Receiver ID)
[ 414.807312] nvme 0000:34:00.0: device [144d:a804] error status/mask=00000010/00504000
[ 414.815305] nvme 0000:34:00.0: [ 4] DLP (First)
[ 414.821768] pcieport 0000:30:03.0: AER: broadcast slot_reset message
Capitalize subject lines to match history (use "git log --oneline
drivers/pci/pcie/aer.c" to see it).
Remove timestamps since they don't help understand the problem.
Indent the quoted material two spaces.
Wrap commit log to fit in 75 columns (except the quoted material;
don't insert line breaks there).
Will do.
Signed-off-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx>
---
drivers/pci/pci.h | 1 +
drivers/pci/pcie/aer.c | 50 ++++++++++++++++++++++++++++++++++++++++++
drivers/pci/pcie/err.c | 6 +++++
3 files changed, 57 insertions(+)
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 0866f79aec54..143f960a813d 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -505,6 +505,7 @@ struct aer_err_info {
};
int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info);
+int aer_get_device_fatal_error_info(struct pci_dev *dev, struct aer_err_info *info);
void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);
#endif /* CONFIG_PCIEAER */
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 13b8586924ea..0c1e382ce117 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -1252,6 +1252,56 @@ int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
return 1;
}
+/**
+ * aer_get_device_fatal_error_info - read fatal error status from EP or RCiEP
+ * and store it to info
+ * @dev: pointer to the device expected to have a error record
+ * @info: pointer to structure to store the error record
+ *
+ * Return 1 on success, 0 on error.
Backwards from the usual return value convention.
Yes. As @Keith pointed, aer_get_device_fatal_error_info() is copied from
aer_get_device_error_info(), I will try to add a helper to reduce
duplication.
+ * Note that @info is reused among all error devices. Clear fields properly.
+ */
+int aer_get_device_fatal_error_info(struct pci_dev *dev, struct aer_err_info *info)
+{
+ int type = pci_pcie_type(dev);
+ int aer = dev->aer_cap;
+ u32 aercc;
+
+ pci_info(dev, "type :%d\n", type);
I don't see this line in the sample output in the commit log. Is this
debug that you intended to remove?
Sorry, I missed this line, will remove it.
+ /* Must reset in this function */
+ info->status = 0;
+ info->tlp_header_valid = 0;
+ info->severity = AER_FATAL;
+
+ /* The device might not support AER */
Unnecessary comment.
Will remove it.
Thank you for valuable comments.
Best Regards,
Shuai
