From c2e4b24ff848bb180f9b9cd873a38327cd219ad2 Mon Sep 17 00:00:00 2001 From: Kapileshwar Singh Date: Tue, 22 Sep 2015 14:22:03 +0100 Subject: [PATCH] tools lib traceevent: Fix string handling in heterogeneous arch environments 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 ignored. 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_FIELD when the field is recognized as a pointer to a string (of the type const char *) Heterogeneous architectures cases below can arise and should be handled: * Traces recorded using 32-bit addresses processed on a 64-bit machine * Traces recorded using 64-bit addresses processed on a 32-bit machine Reported-by: Juri Lelli Signed-off-by: Kapileshwar Singh Reviewed-by: Steven Rostedt Cc: David Ahern Cc: Javi Merino Cc: Jiri Olsa Cc: Namhyung Kim Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1442928123-13824-1-git-send-email-kapileshwar.singh@arm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/traceevent/event-parse.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c index 4d88593..cf42b09 100644 --- a/tools/lib/traceevent/event-parse.c +++ b/tools/lib/traceevent/event-parse.c @@ -3795,7 +3795,7 @@ static void print_str_arg(struct trace_seq *s, void *data, int size, struct format_field *field; struct printk_map *printk; long long val, fval; - unsigned long addr; + unsigned long long addr; char *str; unsigned char *hex; int print; @@ -3828,13 +3828,30 @@ 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); + + /* Handle heterogeneous recording and processing + * architectures + * + * CASE I: + * Traces recorded on 32-bit devices (32-bit + * addressing) and processed on 64-bit devices: + * In this case, only 32 bits should be read. + * + * CASE II: + * Traces recorded on 64 bit devices and processed + * on 32-bit devices: + * In this case, 64 bits must be read. + */ + addr = (pevent->long_size == 8) ? + *(unsigned long long *)(data + field->offset) : + (unsigned long long)*(unsigned int *)(data + field->offset); + /* Check if it matches a print format */ printk = find_printk(pevent, addr); if (printk) trace_seq_puts(s, printk->printk); else - trace_seq_printf(s, "%lx", addr); + trace_seq_printf(s, "%llx", addr); break; } str = malloc(len + 1); -- 2.7.4