[RESEND v13 09/25] PCI/AER: Report CXL or PCIe bus error type in trace logging

Terry Bowman
2025-11-04T17:04:56Z

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.

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>

---

Changes in v12->v13:
- Remove duplicated aer_err_info inline comments. Is already in the
kernel-doc header (Ben)

Changes in v11->v12:
- Change aer_err_info::is_cxl to be bool a bitfield. Update structure
padding. (Lukas)
- Add kernel-doc for 'struct aer_err_info' (Lukas)

Changes in v10->v11:
- Remove duplicate call to trace_aer_event() (Shiju)
- Added Dan William's and Dave Jiang's reviewed-by
---
drivers/pci/pci.h | 37 ++++++++++++++++++++++++++++++-------
drivers/pci/pcie/aer.c | 18 ++++++++++++------
include/ras/ras_event.h | 9 ++++++---
3 files changed, 48 insertions(+), 16 deletions(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index d23430e3eea0..446251892bb7 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -701,31 +701,54 @@ static inline bool pci_dev_binding_disallowed(struct pci_dev *dev)

#define AER_MAX_MULTI_ERR_DEVICES 5 /* Not likely to have more */

+/**
+ * struct aer_err_info - AER Error Information
+ * @dev: Devices reporting error
+ * @ratelimit_print: Flag to log or not log the devices' error. 0=NotLog/1=Log
+ * @error_devnum: Number of devices reporting an error
+ * @level: printk level to use in logging
+ * @id: Value from register PCI_ERR_ROOT_ERR_SRC
+ * @severity: AER severity, 0-UNCOR Non-fatal, 1-UNCOR fatal, 2-COR
+ * @root_ratelimit_print: Flag to log or not log the root's error. 0=NotLog/1=Log
+ * @multi_error_valid: If multiple errors are reported
+ * @first_error: First reported error
+ * @is_cxl: Bus type error: 0-PCI Bus error, 1-CXL Bus error
+ * @tlp_header_valid: Indicates if TLP field contains error information
+ * @status: COR/UNCOR error status
+ * @mask: COR/UNCOR mask
+ * @tlp: Transaction packet information
+ */
struct aer_err_info {
struct pci_dev *dev[AER_MAX_MULTI_ERR_DEVICES];
int ratelimit_print[AER_MAX_MULTI_ERR_DEVICES];
int error_dev_num;
- const char *level; /* printk level */
+ const char *level;

unsigned int id:16;

- unsigned int severity:2; /* 0:NONFATAL | 1:FATAL | 2:COR */
- unsigned int root_ratelimit_print:1; /* 0=skip, 1=print */
+ unsigned int severity:2;
+ unsigned int root_ratelimit_print:1;
unsigned int __pad1:4;
unsigned int multi_error_valid:1;

unsigned int first_error:5;
- unsigned int __pad2:2;
+ unsigned int __pad2:1;
+ bool is_cxl:1;
unsigned int tlp_header_valid:1;

- unsigned int status; /* COR/UNCOR Error Status */
- unsigned int mask; /* COR/UNCOR Error Mask */
- struct pcie_tlp_log tlp; /* TLP Header */
+ unsigned int status;
+ unsigned int mask;
+ struct pcie_tlp_log tlp;
};

int aer_get_device_error_info(struct aer_err_info *info, int i);
void aer_print_error(struct aer_err_info *info, int i);

+static inline const char *aer_err_bus(struct aer_err_info *info)
+{
+ return info->is_cxl ? "CXL" : "PCIe";
+}
+
int pcie_read_tlp_log(struct pci_dev *dev, int where, int where2,
unsigned int tlp_len, bool flit,
struct pcie_tlp_log *log);
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index f5f22216bb41..39e99f438563 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -868,6 +868,7 @@ void aer_print_error(struct aer_err_info *info, int i)
struct pci_dev *dev;
int layer, agent, id;
const char *level = info->level;
+ const char *bus_type = aer_err_bus(info);

if (WARN_ON_ONCE(i >= AER_MAX_MULTI_ERR_DEVICES))
return;
@@ -876,23 +877,23 @@ void aer_print_error(struct aer_err_info *info, int i)
id = pci_dev_id(dev);

pci_dev_aer_stats_incr(dev, info);
- trace_aer_event(pci_name(dev), (info->status & ~info->mask),
+ trace_aer_event(pci_name(dev), bus_type, (info->status & ~info->mask),
info->severity, info->tlp_header_valid, &info->tlp);

if (!info->ratelimit_print[i])
return;

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;
}

layer = AER_GET_LAYER_ERROR(info->severity, info->status);
agent = AER_GET_AGENT(info->severity, info->status);

- aer_printk(level, dev, "PCIe Bus Error: severity=%s, type=%s, (%s)\n",
- aer_error_severity_string[info->severity],
+ aer_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]);

aer_printk(level, dev, " device [%04x:%04x] error status/mask=%08x/%08x\n",
@@ -926,6 +927,7 @@ 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 = {
@@ -946,9 +948,12 @@ void pci_print_aer(struct pci_dev *dev, int aer_severity,

info.status = status;
info.mask = mask;
+ info.is_cxl = pcie_is_cxl(dev);
+
+ bus_type = aer_err_bus(&info);

pci_dev_aer_stats_incr(dev, &info);
- trace_aer_event(pci_name(dev), (status & ~mask),
+ trace_aer_event(pci_name(dev), bus_type, (status & ~mask),
aer_severity, tlp_header_valid, &aer->header_log);

if (!aer_ratelimit(dev, info.severity))
@@ -1309,6 +1314,7 @@ int aer_get_device_error_info(struct aer_err_info *info, int i)
/* 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 c8cd0f00c845..85dbafec6ad1 100644
--- a/include/ras/ras_event.h
+++ b/include/ras/ras_event.h
@@ -298,15 +298,17 @@ 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)
@@ -315,6 +317,7 @@ 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;
@@ -326,8 +329,8 @@ 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