x86, cpu: disable LTO for cpu.c

Clang incorrectly inlines functions with differing stack protector
attributes, which breaks __restore_processor_state() that relies on
stack protector being disabled. This change disables LTO for cpu.c
to work aroung the bug.

Link: https://bugs.llvm.org/show_bug.cgi?id=47479
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
This commit is contained in:
Sami Tolvanen 2020-09-16 12:57:56 -07:00 committed by Kees Cook
parent e242db40be
commit d2dcd3e374
1 changed files with 4 additions and 0 deletions

View File

@ -5,5 +5,9 @@ OBJECT_FILES_NON_STANDARD_hibernate_asm_$(BITS).o := y
# itself be stack-protected # itself be stack-protected
CFLAGS_cpu.o := -fno-stack-protector CFLAGS_cpu.o := -fno-stack-protector
# Clang may incorrectly inline functions with stack protector enabled into
# __restore_processor_state(): https://bugs.llvm.org/show_bug.cgi?id=47479
CFLAGS_REMOVE_cpu.o := $(CC_FLAGS_LTO)
obj-$(CONFIG_PM_SLEEP) += cpu.o obj-$(CONFIG_PM_SLEEP) += cpu.o
obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o hibernate.o obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o hibernate.o