On 12/07/2019 11:15, Naohiro Aota wrote:
> Running "make" on an already compiled kernel tree will rebuild the kernel
> even without any modifications:
>
> $ make ARCH=arm64 CROSS_COMPILE=/usr/bin/aarch64-unknown-linux-gnu-
> arch/arm64/Makefile:58: CROSS_COMPILE_COMPAT not defined or empty, the compat
> vDSO will not be built
> CALL scripts/checksyscalls.sh
> CALL scripts/atomic/check-atomics.sh
> VDSOCHK arch/arm64/kernel/vdso/vdso.so.dbg
> VDSOSYM include/generated/vdso-offsets.h
> CHK include/generated/compile.h
> CC arch/arm64/kernel/signal.o
> CC arch/arm64/kernel/vdso.o
> CC arch/arm64/kernel/signal32.o
> LD arch/arm64/kernel/vdso/vdso.so.dbg
> OBJCOPY arch/arm64/kernel/vdso/vdso.so
> AS arch/arm64/kernel/vdso/vdso.o
> AR arch/arm64/kernel/vdso/built-in.a
> AR arch/arm64/kernel/built-in.a
> GEN .version
> CHK include/generated/compile.h
> UPD include/generated/compile.h
> CC init/version.o
> AR init/built-in.a
> LD vmlinux.o
>
> This is the same bug fixed in commit 92a4728608a8 ("x86/boot: Fix
> if_changed build flip/flop bug"). We cannot use two "if_changed" in one
> target. Fix this build bug by merging two commands into one function.
>
> Cc: Masahiro Yamada <yamada.masah...@socionext.com>
> Fixes: 28b1a824a4f4 ("arm64: vdso: Substitute gettimeofday() with C
> implementation")
> Signed-off-by: Naohiro Aota <naohiro.a...@wdc.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frasc...@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frasc...@arm.com>
> ---
> arch/arm64/kernel/vdso/Makefile | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
> index 4ab863045188..068c614b1231 100644
> --- a/arch/arm64/kernel/vdso/Makefile
> +++ b/arch/arm64/kernel/vdso/Makefile
> @@ -57,8 +57,7 @@ $(obj)/vdso.o : $(obj)/vdso.so
>
> # Link rule for the .so file, .lds has to be first
> $(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
> - $(call if_changed,ld)
> - $(call if_changed,vdso_check)
> + $(call if_changed,ld_and_vdso_check)
>
> # Strip rule for the .so file
> $(obj)/%.so: OBJCOPYFLAGS := -S
> @@ -77,6 +76,9 @@ include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
> quiet_cmd_vdsocc = VDSOCC $@
> cmd_vdsocc = $(CC) $(a_flags) $(c_flags) -c -o $@ $<
>
> +quiet_cmd_ld_and_vdso_check = LD $@
> + cmd_ld_and_vdso_check = $(cmd_ld); $(cmd_vdso_check)
> +
> # Install commands for the unstripped file
> quiet_cmd_vdso_install = INSTALL $@
> cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
>
--
Regards,
Vincenzo
