[PATCH] perf timechart: Fix SIBGUS error on sparc64

From: David Ahern
Date: Tue Mar 24 2015 - 16:14:50 EST


perf timechart -T on sparc64 is terminating due to SIGBUS. Backtrace:

Program received signal SIGBUS, Bus error.
0x0000000000173d7c in perf_evsel__intval (evsel=<value optimized out>, sample=0x7feffffda28, name=0x289b28 "prev_state")
at util/evsel.c:1918
1918 util/evsel.c: No such file or directory.
in util/evsel.c
Missing separate debuginfos, use: debuginfo-install audit-libs-2.3.7-1.0.1.el6.sparc64 bzip2-libs-1.0.5-7.el6_0.sparc64 elfutils-libelf-0.155-2.0.3.el6.sparc64 elfutils-libs-0.155-2.0.3.el6.sparc64 glibc-2.12-1.132.0.8.el6_5.sparc64 numactl-2.0.7-8.el6.sparc64 python-libs-2.6.6-52.0.2.el6.sparc64 slang-2.2.1-1.el6.sparc64 xz-libs-4.999.9-0.3.beta.20091007git.el6.sparc64 zlib-1.2.3-29.el6.sparc64
(gdb) bt
0 0x0000000000173d7c in perf_evsel__intval (evsel=<value optimized out>, sample=0x7feffffda28,
name=0x289b28 "prev_state") at util/evsel.c:1918
1 0x0000000000123b94 in process_sample_sched_switch (tchart=0x7feffffe040, evsel=0x4ca850, sample=0x7feffffda28,
backtrace=0xc39010 "") at builtin-timechart.c:627
2 0x0000000000122828 in process_sample_event (tool=0x7feffffe040, event=<value optimized out>, sample=0x7feffffda28,
evsel=0x4ca850, machine=0x4c9c88) at builtin-timechart.c:569

Another extended load on unaligned pointer. As before fix by copying to
a temporary variable using memcpy.

Signed-off-by: David Ahern <david.ahern@xxxxxxxxxx>
---
tools/perf/util/evsel.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index daa053d..ef20371 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1925,7 +1925,7 @@ u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
value = *(u32 *)ptr;
break;
case 8:
- value = *(u64 *)ptr;
+ memcpy(&value, ptr, sizeof(u64));
break;
default:
return 0;
--
1.7.1

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