4.9-stable review patch. If anyone has any objections, please let me know.
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From: Taeung Song treeze.taeung@gmail.com
[ Upstream commit 6ebd2547dd24daf95a21b2bc59931de8502afcc3 ]
It is wrong way to read link name from a build-id file. Because a build-id file is not anymore a symbolic link but build-id directory of it is symbolic link, so fix it.
For example, if build-id file name gotten from dso__build_id_filename() is as below,
/root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1/elf
To correctly read link name of build-id, use the build-id dir path that is a symbolic link, instead of the above build-id file name like below.
/root/.debug/.build-id/4f/75c7d197c951659d1c1b8b5fd49bcdf8f3f8b1
Signed-off-by: Taeung Song treeze.taeung@gmail.com Cc: Jiri Olsa jolsa@redhat.com Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Wang Nan wangnan0@huawei.com Link: http://lkml.kernel.org/r/1490598638-13947-2-git-send-email-treeze.taeung@gma... Fixes: 01412261d994 ("perf buildid-cache: Use path/to/bin/buildid/elf instead of path/to/bin/buildid") Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/perf/util/annotate.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
--- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -1250,6 +1250,7 @@ static int dso__disassemble_filename(str { char linkname[PATH_MAX]; char *build_id_filename; + char *build_id_path = NULL;
if (dso->symtab_type == DSO_BINARY_TYPE__KALLSYMS && !dso__is_kcore(dso)) @@ -1265,8 +1266,14 @@ static int dso__disassemble_filename(str goto fallback; }
+ build_id_path = strdup(filename); + if (!build_id_path) + return -1; + + dirname(build_id_path); + if (dso__is_kcore(dso) || - readlink(filename, linkname, sizeof(linkname)) < 0 || + readlink(build_id_path, linkname, sizeof(linkname)) < 0 || strstr(linkname, DSO__NAME_KALLSYMS) || access(filename, R_OK)) { fallback: @@ -1278,6 +1285,7 @@ fallback: __symbol__join_symfs(filename, filename_size, dso->long_name); }
+ free(build_id_path); return 0; }