Re: [PATCH v8 02/16] PCI/AER: Modify AER driver logging to report CXL or PCIe bus error type
From: Bjorn Helgaas
Date: Thu Mar 27 2025 - 12:50:12 EST
On Wed, Mar 26, 2025 at 08:47:03PM -0500, Terry Bowman wrote:
> The AER service driver and aer_event tracing currently log 'PCIe Bus Type'
> for all errors. Update the driver and aer_event tracing to log 'CXL Bus
> Type' for CXL device errors.
>
> This requires the AER can identify and distinguish between PCIe errors and
> CXL errors.
>
> Introduce boolean 'is_cxl' to 'struct aer_err_info'. Add assignment in
> aer_get_device_error_info() and pci_print_aer().
>
> Update the aer_event trace routine to accept a bus type string parameter.
> +++ b/drivers/pci/pci.h
> @@ -533,6 +533,7 @@ static inline bool pci_dev_test_and_set_removed(struct pci_dev *dev)
> struct aer_err_info {
> struct pci_dev *dev[AER_MAX_MULTI_ERR_DEVICES];
> int error_dev_num;
> + bool is_cxl;
>
> unsigned int id:16;
>
> @@ -549,6 +550,11 @@ struct aer_err_info {
> struct pcie_tlp_log tlp; /* TLP Header */
> };
>
> +static inline const char *aer_err_bus(struct aer_err_info *info)
> +{
> + return info->is_cxl ? "CXL" : "PCIe";
I don't really see the point in adding struct aer_err_info.is_cxl.
Every place where we call aer_err_bus() to look at it, we also have
the struct pci_dev pointer, so we could just as easily use
pcie_is_cxl() here.
> +}
> +
> int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info);
> void aer_print_error(struct pci_dev *dev, struct aer_err_info *info);
>
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index 508474e17183..83f2069f111e 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -694,13 +694,14 @@ static void __aer_print_error(struct pci_dev *dev,
>
> void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
> {
> + const char *bus_type = aer_err_bus(info);
> int layer, agent;
> int id = pci_dev_id(dev);
> const char *level;
>
> if (!info->status) {
> - pci_err(dev, "PCIe Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
> - aer_error_severity_string[info->severity]);
> + pci_err(dev, "%s Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n",
> + bus_type, aer_error_severity_string[info->severity]);
> goto out;
> }
>
> @@ -709,8 +710,8 @@ void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
>
> level = (info->severity == AER_CORRECTABLE) ? KERN_WARNING : KERN_ERR;
>
> - pci_printk(level, dev, "PCIe Bus Error: severity=%s, type=%s, (%s)\n",
> - aer_error_severity_string[info->severity],
> + pci_printk(level, dev, "%s Bus Error: severity=%s, type=%s, (%s)\n",
> + bus_type, aer_error_severity_string[info->severity],
> aer_error_layer[layer], aer_agent_string[agent]);
>
> pci_printk(level, dev, " device [%04x:%04x] error status/mask=%08x/%08x\n",
> @@ -725,7 +726,7 @@ void aer_print_error(struct pci_dev *dev, struct aer_err_info *info)
> if (info->id && info->error_dev_num > 1 && info->id == id)
> pci_err(dev, " Error of this Agent is reported first\n");
>
> - trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask),
> + trace_aer_event(dev_name(&dev->dev), bus_type, (info->status & ~info->mask),
> info->severity, info->tlp_header_valid, &info->tlp);
> }
>
> @@ -759,6 +760,7 @@ EXPORT_SYMBOL_GPL(cper_severity_to_aer);
> void pci_print_aer(struct pci_dev *dev, int aer_severity,
> struct aer_capability_regs *aer)
> {
> + const char *bus_type;
> int layer, agent, tlp_header_valid = 0;
> u32 status, mask;
> struct aer_err_info info;
> @@ -780,6 +782,9 @@ void pci_print_aer(struct pci_dev *dev, int aer_severity,
> info.status = status;
> info.mask = mask;
> info.first_error = PCI_ERR_CAP_FEP(aer->cap_control);
> + info.is_cxl = pcie_is_cxl(dev);
> +
> + bus_type = aer_err_bus(&info);
>
> pci_err(dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask);
> __aer_print_error(dev, &info);
> @@ -793,7 +798,7 @@ void pci_print_aer(struct pci_dev *dev, int aer_severity,
> if (tlp_header_valid)
> pcie_print_tlp_log(dev, &aer->header_log, dev_fmt(" "));
>
> - trace_aer_event(dev_name(&dev->dev), (status & ~mask),
> + trace_aer_event(dev_name(&dev->dev), bus_type, (status & ~mask),
> aer_severity, tlp_header_valid, &aer->header_log);
> }
> EXPORT_SYMBOL_NS_GPL(pci_print_aer, "CXL");
> @@ -1211,6 +1216,7 @@ int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
> /* Must reset in this function */
> info->status = 0;
> info->tlp_header_valid = 0;
> + info->is_cxl = pcie_is_cxl(dev);
>
> /* The device might not support AER */
> if (!aer)
> diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h
> index e5f7ee0864e7..1bf8e7050ba8 100644
> --- a/include/ras/ras_event.h
> +++ b/include/ras/ras_event.h
> @@ -297,15 +297,17 @@ TRACE_EVENT(non_standard_event,
>
> TRACE_EVENT(aer_event,
> TP_PROTO(const char *dev_name,
> + const char *bus_type,
> const u32 status,
> const u8 severity,
> const u8 tlp_header_valid,
> struct pcie_tlp_log *tlp),
>
> - TP_ARGS(dev_name, status, severity, tlp_header_valid, tlp),
> + TP_ARGS(dev_name, bus_type, status, severity, tlp_header_valid, tlp),
>
> TP_STRUCT__entry(
> __string( dev_name, dev_name )
> + __string( bus_type, bus_type )
> __field( u32, status )
> __field( u8, severity )
> __field( u8, tlp_header_valid)
> @@ -314,6 +316,7 @@ TRACE_EVENT(aer_event,
>
> TP_fast_assign(
> __assign_str(dev_name);
> + __assign_str(bus_type);
> __entry->status = status;
> __entry->severity = severity;
> __entry->tlp_header_valid = tlp_header_valid;
> @@ -325,8 +328,8 @@ TRACE_EVENT(aer_event,
> }
> ),
>
> - TP_printk("%s PCIe Bus Error: severity=%s, %s, TLP Header=%s\n",
> - __get_str(dev_name),
> + TP_printk("%s %s Bus Error: severity=%s, %s, TLP Header=%s\n",
> + __get_str(dev_name), __get_str(bus_type),
> __entry->severity == AER_CORRECTABLE ? "Corrected" :
> __entry->severity == AER_FATAL ?
> "Fatal" : "Uncorrected, non-fatal",
> --
> 2.34.1
>