diff options
| author | Krister Johansen | 2017-01-05 22:23:31 -0800 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo | 2017-01-31 16:19:06 -0300 |
| commit | 9c68ae98c6f714ef573826cfc9055af1bd5e97b1 (patch) | |
| tree | f87b3cf4812f70534c8cc2309c934d6ffab69bbc /tools/perf/util/hist.c | |
| parent | c0621acf45a9d8c3b501633b5eca11495fff8f66 (diff) | |
perf callchain: Reference count maps
If dso__load_kcore frees all of the existing maps, but one has already
been attached to a callchain cursor node, then we can get a SIGSEGV in
any function that happens to try to use this invalid cursor. Use the
existing map refcount mechanism to forestall cleanup of a map until the
cursor iterates past the node.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@kernel.org
Fixes: 84c2cafa2889 ("perf tools: Reference count struct map")
Link: http://lkml.kernel.org/r/20170106062331.GB2707@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/hist.c')
| -rw-r--r-- | tools/perf/util/hist.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c index cff2e9041b15..32c6a939e4cc 100644 --- a/tools/perf/util/hist.c +++ b/tools/perf/util/hist.c @@ -1,6 +1,7 @@ #include "util.h" #include "build-id.h" #include "hist.h" +#include "map.h" #include "session.h" #include "sort.h" #include "evlist.h" @@ -1019,6 +1020,10 @@ int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al, int max_stack_depth, void *arg) { int err, err2; + struct map *alm = NULL; + + if (al && al->map) + alm = map__get(al->map); err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent, iter->evsel, al, max_stack_depth); @@ -1058,6 +1063,8 @@ out: if (!err) err = err2; + map__put(alm); + return err; } |