diff options
| author | Carlos Llamas <cmllamas@google.com> | 2023-09-29 03:48:17 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-01-12 15:20:46 -0800 |
| commit | efbd6398353315b7018e6943e41fee9ec35e875f (patch) | |
| tree | 52fe6c4439fa51a35e3c3f734795d68f901b783b /scripts/decode_stacktrace.sh | |
| parent | cc478e0b6bdffd20561e1a07941a65f6c8962cab (diff) | |
| download | lwn-efbd6398353315b7018e6943e41fee9ec35e875f.tar.gz lwn-efbd6398353315b7018e6943e41fee9ec35e875f.zip | |
scripts/decode_stacktrace.sh: optionally use LLVM utilities
GNU's addr2line can have problems parsing a vmlinux built with LLVM,
particularly when LTO was used. In order to decode the traces correctly
this patch adds the ability to switch to LLVM's utilities readelf and
addr2line. The same approach is followed by Will in [1].
Before:
$ scripts/decode_stacktrace.sh vmlinux < kernel.log
[17716.240635] Call trace:
[17716.240646] skb_cow_data (??:?)
[17716.240654] esp6_input (ld-temp.o:?)
[17716.240666] xfrm_input (ld-temp.o:?)
[17716.240674] xfrm6_rcv (??:?)
[...]
After:
$ LLVM=1 scripts/decode_stacktrace.sh vmlinux < kernel.log
[17716.240635] Call trace:
[17716.240646] skb_cow_data (include/linux/skbuff.h:2172 net/core/skbuff.c:4503)
[17716.240654] esp6_input (net/ipv6/esp6.c:977)
[17716.240666] xfrm_input (net/xfrm/xfrm_input.c:659)
[17716.240674] xfrm6_rcv (net/ipv6/xfrm6_input.c:172)
[...]
Note that one could set CROSS_COMPILE=llvm- instead to hack around this
issue. However, doing so can break the decodecode routine as it will
force the selection of other LLVM utilities down the line e.g. llvm-as.
[1] https://lore.kernel.org/all/20230914131225.13415-3-will@kernel.org/
Link: https://lkml.kernel.org/r/20230929034836.403735-1-cmllamas@google.com
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Elliot Berman <quic_eberman@quicinc.com>
Tested-by: Justin Stitt <justinstitt@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: John Stultz <jstultz@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Tom Rix <trix@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'scripts/decode_stacktrace.sh')
| -rwxr-xr-x | scripts/decode_stacktrace.sh | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh index cb980b144ca1..fa5be6f57b00 100755 --- a/scripts/decode_stacktrace.sh +++ b/scripts/decode_stacktrace.sh @@ -16,6 +16,21 @@ elif type c++filt >/dev/null 2>&1 ; then cppfilt_opts=-i fi +UTIL_SUFFIX= +if [[ -z ${LLVM:-} ]]; then + UTIL_PREFIX=${CROSS_COMPILE:-} +else + UTIL_PREFIX=llvm- + if [[ ${LLVM} == */ ]]; then + UTIL_PREFIX=${LLVM}${UTIL_PREFIX} + elif [[ ${LLVM} == -* ]]; then + UTIL_SUFFIX=${LLVM} + fi +fi + +READELF=${UTIL_PREFIX}readelf${UTIL_SUFFIX} +ADDR2LINE=${UTIL_PREFIX}addr2line${UTIL_SUFFIX} + if [[ $1 == "-r" ]] ; then vmlinux="" basepath="auto" @@ -75,7 +90,7 @@ find_module() { if [[ "$modpath" != "" ]] ; then for fn in $(find "$modpath" -name "${module//_/[-_]}.ko*") ; do - if readelf -WS "$fn" | grep -qwF .debug_line ; then + if ${READELF} -WS "$fn" | grep -qwF .debug_line ; then echo $fn return fi @@ -169,7 +184,7 @@ parse_symbol() { if [[ $aarray_support == true && "${cache[$module,$address]+isset}" == "isset" ]]; then local code=${cache[$module,$address]} else - local code=$(${CROSS_COMPILE}addr2line -i -e "$objfile" "$address" 2>/dev/null) + local code=$(${ADDR2LINE} -i -e "$objfile" "$address" 2>/dev/null) if [[ $aarray_support == true ]]; then cache[$module,$address]=$code fi |