kbuild: fix false positive warning/error about missing libelf

[ Upstream commit ef7cfd00b2 ]

For the same reason as commit 25896d073d ("x86/build: Fix compiler
support check for CONFIG_RETPOLINE"), you cannot put this $(error ...)
into the parse stage of the top Makefile.

Perhaps I'd propose a more sophisticated solution later, but this is
the best I can do for now.

Link: https://lkml.org/lkml/2017/12/25/211
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reported-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reported-by: Qian Cai <cai@lca.pw>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Masahiro Yamada 2018-12-18 14:25:41 +09:00 committed by Greg Kroah-Hartman
parent bb2509c12b
commit b08f331e84
1 changed files with 8 additions and 5 deletions

View File

@ -954,11 +954,6 @@ ifdef CONFIG_STACK_VALIDATION
ifeq ($(has_libelf),1)
objtool_target := tools/objtool FORCE
else
ifdef CONFIG_UNWINDER_ORC
$(error "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
else
$(warning "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel")
endif
SKIP_STACK_VALIDATION := 1
export SKIP_STACK_VALIDATION
endif
@ -1102,6 +1097,14 @@ uapi-asm-generic:
PHONY += prepare-objtool
prepare-objtool: $(objtool_target)
ifeq ($(SKIP_STACK_VALIDATION),1)
ifdef CONFIG_UNWINDER_ORC
@echo "error: Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
@false
else
@echo "warning: Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel" >&2
endif
endif
# Check for CONFIG flags that require compiler support. Abort the build
# after .config has been processed, but before the kernel build starts.