From: Ard Biesheuvel <ardb@xxxxxxxxxx> The purgatory is a completely separate ELF executable carried inside the kernel as an opaque binary blob. This means that function entry padding and the associated ELF metadata are not exposed to the branch tracking and code patching machinery, and can there be dropped from the purgatory binary. Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> --- arch/x86/purgatory/Makefile | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile index a18591f6e6d9..2df4a4b70ff5 100644 --- a/arch/x86/purgatory/Makefile +++ b/arch/x86/purgatory/Makefile @@ -23,6 +23,9 @@ KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%,$(KBUILD_CF # by kexec. Remove -flto=* flags. KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_LTO),$(KBUILD_CFLAGS)) +# Drop the function entry padding, which is not needed here +KBUILD_CFLAGS := $(filter-out $(PADDING_CFLAGS),$(KBUILD_CFLAGS)) + # When linking purgatory.ro with -r unresolved symbols are not checked, # also link a purgatory.chk binary without -r to check for unresolved symbols. PURGATORY_LDFLAGS := -e purgatory_start -z nodefaultlib -- 2.44.0.769.g3c40516874-goog _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
