From a6aaeb841198016083663ae56c568de4e065d090 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 26 Feb 2021 15:25:48 +0900 Subject: kbuild: fix UNUSED_KSYMS_WHITELIST for Clang LTO Commit fbe078d397b4 ("kbuild: lto: add a default list of used symbols") does not work as expected if the .config file has already specified CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling CONFIG_LTO_CLANG. So, the user-supplied whitelist and LTO-specific white list must be independent of each other. I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO handle whitelists in the same way. Fixes: fbe078d397b4 ("kbuild: lto: add a default list of used symbols") Signed-off-by: Masahiro Yamada Tested-by: Sedat Dilek --- scripts/gen_autoksyms.sh | 35 ++++++++++++++++++++++++++--------- scripts/lto-used-symbollist.txt | 6 ------ 2 files changed, 26 insertions(+), 15 deletions(-) delete mode 100644 scripts/lto-used-symbollist.txt (limited to 'scripts') diff --git a/scripts/gen_autoksyms.sh b/scripts/gen_autoksyms.sh index d54dfba15bf2..da320151e7c3 100755 --- a/scripts/gen_autoksyms.sh +++ b/scripts/gen_autoksyms.sh @@ -19,7 +19,26 @@ esac # We need access to CONFIG_ symbols . include/config/auto.conf -ksym_wl=/dev/null +needed_symbols= + +# Special case for modversions (see modpost.c) +if [ -n "$CONFIG_MODVERSIONS" ]; then + needed_symbols="$needed_symbols module_layout" +fi + +# With CONFIG_LTO_CLANG, LLVM bitcode has not yet been compiled into a binary +# when the .mod files are generated, which means they don't yet contain +# references to certain symbols that will be present in the final binaries. +if [ -n "$CONFIG_LTO_CLANG" ]; then + # intrinsic functions + needed_symbols="$needed_symbols memcpy memmove memset" + # ftrace + needed_symbols="$needed_symbols _mcount" + # stack protector symbols + needed_symbols="$needed_symbols __stack_chk_fail __stack_chk_guard" +fi + +ksym_wl= if [ -n "$CONFIG_UNUSED_KSYMS_WHITELIST" ]; then # Use 'eval' to expand the whitelist path and check if it is relative eval ksym_wl="$CONFIG_UNUSED_KSYMS_WHITELIST" @@ -40,16 +59,14 @@ cat > "$output_file" << EOT EOT [ -f modules.order ] && modlist=modules.order || modlist=/dev/null -sed 's/ko$/mod/' $modlist | -xargs -n1 sed -n -e '2{s/ /\n/g;/^$/!p;}' -- | -cat - "$ksym_wl" | + +{ + sed 's/ko$/mod/' $modlist | xargs -n1 sed -n -e '2p' + echo "$needed_symbols" + [ -n "$ksym_wl" ] && cat "$ksym_wl" +} | sed -e 's/ /\n/g' | sed -n -e '/^$/!p' | # Remove the dot prefix for ppc64; symbol names with a dot (.) hold entry # point addresses. sed -e 's/^\.//' | sort -u | sed -e 's/\(.*\)/#define __KSYM_\1 1/' >> "$output_file" - -# Special case for modversions (see modpost.c) -if [ -n "$CONFIG_MODVERSIONS" ]; then - echo "#define __KSYM_module_layout 1" >> "$output_file" -fi diff --git a/scripts/lto-used-symbollist.txt b/scripts/lto-used-symbollist.txt deleted file mode 100644 index 406ada65e926..000000000000 --- a/scripts/lto-used-symbollist.txt +++ /dev/null @@ -1,6 +0,0 @@ -memcpy -memmove -memset -_mcount -__stack_chk_fail -__stack_chk_guard -- cgit v1.2.3