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| author | Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | 2014-02-05 05:18:58 +0000 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2014-02-10 11:34:30 -0300 |
| commit | 981a23792cd02631f8cd5dd65753208a44de5ae1 (patch) | |
| tree | 88ee1c76011f20ac7a8ca0f9700bb2a57c909f7a /tools | |
| parent | 0e9f2204cfa6d79abe3e525ddf7c4ab5792cc751 (diff) | |
| download | linux-981a23792cd02631f8cd5dd65753208a44de5ae1.tar.gz linux-981a23792cd02631f8cd5dd65753208a44de5ae1.tar.bz2 linux-981a23792cd02631f8cd5dd65753208a44de5ae1.zip | |
perf probe: Do not add offset twice to uprobe address
Fix perf-probe not to add offset value twice to uprobe probe address
when post processing.
The tevs[i].point.address struct member is the address of symbol+offset,
but current perf-probe adjusts the point.address by adding the offset.
As a result, the probe address becomes symbol+offset+offset. This may
cause unexpected code corruption. Urgent fix is needed.
Without this fix:
---
# ./perf probe -x ./perf dso__load_vmlinux+4
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d2b8)
# nm ./perf.orig | grep dso__load_vmlinux\$
000000000046d0a0 T dso__load_vmlinux
---
You can see the given offset is 3 but the actual probed address is
dso__load_vmlinux+8.
With this fix:
---
# ./perf probe -x ./perf dso__load_vmlinux+4
# ./perf probe -l
probe_perf:dso__load_vmlinux (on 0x000000000006d2b4)
---
Now the problem is fixed.
Note: This bug is introduced by
commit fb7345bbf7fad9bf72ef63a19c707970b9685812
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140205051858.6519.27314.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/util/probe-event.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index a8a9b6cd93a8..d8b048c20cde 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -336,8 +336,8 @@ static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, return ret; for (i = 0; i < ntevs && ret >= 0; i++) { + /* point.address is the addres of point.symbol + point.offset */ offset = tevs[i].point.address - stext; - offset += tevs[i].point.offset; tevs[i].point.offset = 0; zfree(&tevs[i].point.symbol); ret = e_snprintf(buf, 32, "0x%lx", offset); |