[PATCH 3/3] kbuild: check the presence of lzo and lz4 tools when necessary

[Masahiro Yamada]

If CONFIG_KERNEL_LZ4 is enabled without lz4 tool installed on the
system, the build fails at the very last stage (reported by
Borislav Petkov [1]).

  LZO     arch/x86/boot/compressed/vmlinux.bin.lzo
/bin/sh: 1: lzop: not found
arch/x86/boot/compressed/Makefile:141: recipe for target 'arch/x86/boot/compressed/vmlinux.bin.lzo' failed
make[2]: *** [arch/x86/boot/compressed/vmlinux.bin.lzo] Error 1
arch/x86/boot/Makefile:112: recipe for target 'arch/x86/boot/compressed/vmlinux' failed
make[1]: *** [arch/x86/boot/compressed/vmlinux] Error 2
arch/x86/Makefile:284: recipe for target 'bzImage' failed
make: *** [bzImage] Error 2

Check the tools in scripts/Makefile.toolcheck to fail the build
earlier with a more readable message.

[1] https://patchwork.kernel.org/patch/10635381/

Suggested-by: Borislav Petkov <bp@xxxxxxx>
Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

 scripts/Makefile.toolcheck | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/scripts/Makefile.toolcheck b/scripts/Makefile.toolcheck
index bc26fc0..5e336e4 100644
--- a/scripts/Makefile.toolcheck
+++ b/scripts/Makefile.toolcheck
@@ -17,6 +17,14 @@ msg_stack_validation = "libelf is necessary for building the objtool." \
 		       "Please install libelf-dev, libelf-devel or elfutils-libelf-devel."
 toolcheck-$(CONFIG_STACK_VALIDATION) += stack_validation
 
+chk_lzo = command -v lzop
+msg_lzo = "lzo tool not found. Please install it."
+toolcheck-$(CONFIG_KERNEL_LZO) += lzo
+
+chk_lz4 = command -v lz4c
+msg_lz4 = "lz4 tool not found. Please install it."
+toolcheck-$(CONFIG_KERNEL_LZ4) += lz4
+
 PHONY += $(toolcheck-y)
 __toolcheck: $(toolcheck-y)
 
-- 
2.7.4