When a trace recorded on a 32-bit device is processed with a 64-bit
binary, the higher 32-bits of the address need to be masked.
The lack of this results in the output of the 64-bit pointer
value to the trace as the 32-bit address lookup fails in find_printk.
Before:
burn-1778 [003] 548.600305: bputs: 0xc0046db2s: 2cec5c058d98c
After:
burn-1778 [003] 548.600305: bputs: 0xc0046db2s: RT throttling activated
The problem occurs in PRINT_FEILD when the field is recognized as a pointer
to a string (of the type const char *)
Cc: Steven Rostedt <rost...@goodmis.org>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Javi Merino <javi.mer...@arm.com>
Cc: David Ahern <dsah...@gmail.com>
Cc: Jiri Olsa <jo...@kernel.org>
Reported-by: Juri-Lelli <juri.le...@arm.com>
Signed-off-by: Kapileshwar Singh <kapileshwar.si...@arm.com>
---
tools/lib/traceevent/event-parse.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/tools/lib/traceevent/event-parse.c
b/tools/lib/traceevent/event-parse.c
index 4d885934b919..39163ea4a048 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -3829,6 +3829,17 @@ static void print_str_arg(struct trace_seq *s, void
*data, int size,
if (!(field->flags & FIELD_IS_ARRAY) &&
field->size == pevent->long_size) {
addr = *(unsigned long *)(data + field->offset);
+
+ /* In case the long_size is 4. The higher 32bits
+ * need to be masked for a successful lookup in
+ * in the printk table. As the pointers are 32-bit
+ * long. This could happen if a trace recorded on
+ * 32-bit platform is processed using a 64-bit
+ * binary
+ */
+ if (pevent->long_size == 4)
+ addr = addr & 0xffffffff;
+
/* Check if it matches a print format */
printk = find_printk(pevent, addr);
if (printk)
--
1.9.1
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