From: Josh Poimboeuf Date: Mon, 18 Apr 2022 16:50:20 +0000 (-0700) Subject: objtool: Enable unreachable warnings for CLANG LTO X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4a5de9b76fcb3f477f73d5a63f6e27709e8af81f;p=linux.git objtool: Enable unreachable warnings for CLANG LTO With IBT support in, objtool is now fully capable of following vmlinux code flow in LTO mode. Start reporting unreachable warnings for Clang LTO as well. Fixes: ed53a0d97192 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls") Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/7b12df54bceeb0761fe9fc8269ea0c00501214a9.1650300597.git.jpoimboe@redhat.com --- diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 9717e6f6fb314..33c1ed5815229 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -231,7 +231,7 @@ objtool_args = \ $(if $(part-of-module), --module) \ $(if $(CONFIG_X86_KERNEL_IBT), --lto --ibt) \ $(if $(CONFIG_FRAME_POINTER),, --no-fp) \ - $(if $(CONFIG_GCOV_KERNEL)$(CONFIG_LTO_CLANG), --no-unreachable)\ + $(if $(CONFIG_GCOV_KERNEL), --no-unreachable) \ $(if $(CONFIG_RETPOLINE), --retpoline) \ $(if $(CONFIG_X86_SMAP), --uaccess) \ $(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount) \ diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index 20f44504a644b..9361a1ef02c99 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -140,7 +140,7 @@ objtool_link() if ! is_enabled CONFIG_FRAME_POINTER; then objtoolopt="${objtoolopt} --no-fp" fi - if is_enabled CONFIG_GCOV_KERNEL || is_enabled CONFIG_LTO_CLANG; then + if is_enabled CONFIG_GCOV_KERNEL; then objtoolopt="${objtoolopt} --no-unreachable" fi if is_enabled CONFIG_RETPOLINE; then