4.4-stable review patch. If anyone has any objections, please let me know.
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From: Namhyung Kim namhyung@kernel.org
[ Upstream commit 94df1040b1e6aacd8dec0ba3c61d7e77cd695f26 ]
If a kernel modules is compressed, it should be decompressed before running objdump to parse binary data correctly. This fixes a failure of object code reading test for me.
Signed-off-by: Namhyung Kim namhyung@kernel.org Acked-by: Adrian Hunter adrian.hunter@intel.com Acked-by: Jiri Olsa jolsa@kernel.org Cc: David Ahern dsahern@gmail.com Cc: Peter Zijlstra a.p.zijlstra@chello.nl Cc: Wang Nan wangnan0@huawei.com Cc: kernel-team@lge.com Link: http://lkml.kernel.org/r/20170608073109.30699-8-namhyung@kernel.org 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/tests/code-reading.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-)
--- a/tools/perf/tests/code-reading.c +++ b/tools/perf/tests/code-reading.c @@ -182,6 +182,8 @@ static int read_object_code(u64 addr, si unsigned char buf2[BUFSZ]; size_t ret_len; u64 objdump_addr; + const char *objdump_name; + char decomp_name[KMOD_DECOMP_LEN]; int ret;
pr_debug("Reading object code for memory address: %#"PRIx64"\n", addr); @@ -242,9 +244,25 @@ static int read_object_code(u64 addr, si state->done[state->done_cnt++] = al.map->start; }
+ objdump_name = al.map->dso->long_name; + if (dso__needs_decompress(al.map->dso)) { + if (dso__decompress_kmodule_path(al.map->dso, objdump_name, + decomp_name, + sizeof(decomp_name)) < 0) { + pr_debug("decompression failed\n"); + return -1; + } + + objdump_name = decomp_name; + } + /* Read the object code using objdump */ objdump_addr = map__rip_2objdump(al.map, al.addr); - ret = read_via_objdump(al.map->dso->long_name, objdump_addr, buf2, len); + ret = read_via_objdump(objdump_name, objdump_addr, buf2, len); + + if (dso__needs_decompress(al.map->dso)) + unlink(objdump_name); + if (ret > 0) { /* * The kernel maps are inaccurate - assume objdump is right in