[PATCH 2/4] scripts/decode_stacktrace: guess basepath if not specified

From: Konstantin Khlebnikov
Date: Mon Jun 22 2020 - 08:33:55 EST


Guess path to kernel sources using known location of symbol "kernel_init".
Make basepath argument optional.

Before:

$ echo 'vfs_open+0x0/0x0' | ./scripts/decode_stacktrace.sh vmlinux ""
vfs_open (home/khlebnikov/src/linux/fs/open.c:912)

After:

$ echo 'vfs_open+0x0/0x0' | ./scripts/decode_stacktrace.sh vmlinux
vfs_open (fs/open.c:912)

Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
---
scripts/decode_stacktrace.sh | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/scripts/decode_stacktrace.sh b/scripts/decode_stacktrace.sh
index 6ec8d6dff86c..b1b85a7b2115 100755
--- a/scripts/decode_stacktrace.sh
+++ b/scripts/decode_stacktrace.sh
@@ -3,14 +3,14 @@
# (c) 2014, Sasha Levin <sasha.levin@xxxxxxxxxx>
#set -x

-if [[ $# < 2 ]]; then
+if [[ $# < 1 ]]; then
echo "Usage:"
- echo " $0 [vmlinux] [base path] [modules path]"
+ echo " $0 <vmlinux> [base path] [modules path]"
exit 1
fi

vmlinux=$1
-basepath=$2
+basepath=${2-auto}
modpath=$3
declare -A cache
declare -A modcache
@@ -152,6 +152,14 @@ handle_line() {
echo "${words[@]}" "$symbol $module"
}

+if [[ $basepath == "auto" ]] ; then
+ module=""
+ symbol="kernel_init+0x0/0x0"
+ parse_symbol
+ basepath=${symbol#kernel_init (}
+ basepath=${basepath%/init/main.c:*)}
+fi
+
while read line; do
# Let's see if we have an address in the line
if [[ $line =~ \[\<([^]]+)\>\] ]] ||