[PATCH v11 09/23] PCI/AER: Report CXL or PCIe bus error type in trace logging

Terry Bowman
2025-08-27T01:37:33Z

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 v10->v11:
- Remove duplicate call to trace_aer_event() (Shiju)
- Added Dan William's and Dave Jiang's reviewed-by
---
drivers/pci/pci.h | 6 ++++++
drivers/pci/pcie/aer.c | 18 ++++++++++++------
include/ras/ras_event.h | 9 ++++++---
3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index c8a0c0ec0073..417a088d815f 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -608,6 +608,7 @@ struct aer_err_info {
int ratelimit_print[AER_MAX_MULTI_ERR_DEVICES];
int error_dev_num;
const char *level; /* printk level */
+ bool is_cxl;

unsigned int id:16;

@@ -628,6 +629,11 @@ struct aer_err_info {
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 29de7ee861f7..1b5f5b0cdc4f 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -837,6 +837,7 @@ 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;
@@ -845,23 +846,23 @@ 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",
@@ -895,6 +896,7 @@ 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 = {
@@ -915,9 +917,12 @@ 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))
@@ -1277,6 +1282,7 @@ 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 14c9f943d53f..080829d59c36 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",
--
2.51.0.rc2.21.ge5ab6b3e5a