[PATCH 01/12] perf probe: Fix regression of variable finder

From: Arnaldo Carvalho de Melo
Date: Fri Sep 23 2011 - 16:27:33 EST


From: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>

Fix to call convert_variable() if previous call does not fail.

To call convert_variable, it ensures "ret" is 0. However, since
"ret" has the return value of synthesize_perf_probe_arg() which
always returns positive value if it succeeded, perf probe doesn't
call convert_variable(). This will cause a SEGV when we add an
event with arguments.

This has to be fixed as it ensures "ret" is greater than 0
(or not negative).

This regression has been introduced by my previous patch, f182e3e1.

Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: yrl.pp-manager.tt@xxxxxxxxxxx
Link: http://lkml.kernel.org/r/20110820053922.3286.65805.stgit@fedora15
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@xxxxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/probe-finder.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 555fc38..5d73262 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -659,7 +659,7 @@ static int find_variable(Dwarf_Die *sc_die, struct probe_finder *pf)
if (!die_find_variable_at(&pf->cu_die, pf->pvar->var, 0, &vr_die))
ret = -ENOENT;
}
- if (ret == 0)
+ if (ret >= 0)
ret = convert_variable(&vr_die, pf);

if (ret < 0)
--
1.6.2.5

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