6.8-stable review patch. If anyone has any objections, please let me know.
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From: Alison Schofield alison.schofield@intel.com
[ Upstream commit 6c871260965255a1c142fb77ccee58b172d1690b ]
The TP_STRUCT__entry that gets assigned the region name, or an empty string if no region is present, is erroneously initialized to the cxl_region pointer. It needs to be properly initialized otherwise it's length is wrong and garbage chars can appear in the kernel trace output: /sys/kernel/tracing/trace
The bad initialization was due in part to a naming conflict with the parameter: struct cxl_region *region. The field 'region' is already exposed externally as the region name, so changing that to something logical, like 'region_name' is not an option. Instead rename the internal only struct cxl_region to the commonly used 'cxlr'.
Impact is that tooling depending on that trace data can miss picking up a valid event when searching by region name. The TP_printk() output, if enabled, does emit the correct region names in the dmesg log.
This was found during testing of the cxl-list option to report media-errors for a region.
Cc: Davidlohr Bueso dave@stgolabs.net Cc: Jonathan Cameron jonathan.cameron@huawei.com Cc: Dave Jiang dave.jiang@intel.com Cc: Vishal Verma vishal.l.verma@intel.com Cc: stable@vger.kernel.org Fixes: ddf49d57b841 ("cxl/trace: Add TRACE support for CXL media-error records") Signed-off-by: Alison Schofield alison.schofield@intel.com Reviewed-by: Ira Weiny ira.weiny@intel.com Acked-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/cxl/core/trace.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/cxl/core/trace.h b/drivers/cxl/core/trace.h index bdf117a33744b..e5f13260fc524 100644 --- a/drivers/cxl/core/trace.h +++ b/drivers/cxl/core/trace.h @@ -646,18 +646,18 @@ u64 cxl_trace_hpa(struct cxl_region *cxlr, struct cxl_memdev *memdev, u64 dpa);
TRACE_EVENT(cxl_poison,
- TP_PROTO(struct cxl_memdev *cxlmd, struct cxl_region *region, + TP_PROTO(struct cxl_memdev *cxlmd, struct cxl_region *cxlr, const struct cxl_poison_record *record, u8 flags, __le64 overflow_ts, enum cxl_poison_trace_type trace_type),
- TP_ARGS(cxlmd, region, record, flags, overflow_ts, trace_type), + TP_ARGS(cxlmd, cxlr, record, flags, overflow_ts, trace_type),
TP_STRUCT__entry( __string(memdev, dev_name(&cxlmd->dev)) __string(host, dev_name(cxlmd->dev.parent)) __field(u64, serial) __field(u8, trace_type) - __string(region, region) + __string(region, cxlr ? dev_name(&cxlr->dev) : "") __field(u64, overflow_ts) __field(u64, hpa) __field(u64, dpa) @@ -677,10 +677,10 @@ TRACE_EVENT(cxl_poison, __entry->source = cxl_poison_record_source(record); __entry->trace_type = trace_type; __entry->flags = flags; - if (region) { - __assign_str(region, dev_name(®ion->dev)); - memcpy(__entry->uuid, ®ion->params.uuid, 16); - __entry->hpa = cxl_trace_hpa(region, cxlmd, + if (cxlr) { + __assign_str(region, dev_name(&cxlr->dev)); + memcpy(__entry->uuid, &cxlr->params.uuid, 16); + __entry->hpa = cxl_trace_hpa(cxlr, cxlmd, __entry->dpa); } else { __assign_str(region, "");