| Message ID | 20211012234606.91717-4-ndesaulniers@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | compat vdso cleanups | expand |
On Tue, Oct 12, 2021 at 04:46:06PM -0700, Nick Desaulniers wrote: > Similar to > commit 231ad7f409f1 ("Makefile: infer --target from ARCH for CC=clang") > There really is no point in setting --target based on > $CROSS_COMPILE_COMPAT for clang when the integrated assembler is being > used. It might be nice to mention commit ef94340583ee ("arm64: vdso32: drop -no-integrated-as flag") here, as that is what flipped on the integrated assembler for this Makefile (and it cannot be turned off). > Allows COMPAT_VDSO to be selected without setting $CROSS_COMPILE_COMPAT > when using clang and lld together. > > Before: > $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 defconfig > $ grep CONFIG_COMPAT_VDSO .config > CONFIG_COMPAT_VDSO=y > $ ARCH=arm64 make -j72 LLVM=1 defconfig > $ grep CONFIG_COMPAT_VDSO .config > $ > > After: > $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 defconfig > $ grep CONFIG_COMPAT_VDSO .config > CONFIG_COMPAT_VDSO=y > $ ARCH=arm64 make -j72 LLVM=1 defconfig > $ grep CONFIG_COMPAT_VDSO .config > CONFIG_COMPAT_VDSO=y > > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Modulo these two nits, this works for me too. Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> > --- > arch/arm64/Kconfig | 3 ++- > arch/arm64/kernel/vdso32/Makefile | 17 +++++------------ > 2 files changed, 7 insertions(+), 13 deletions(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 5c7ae4c3954b..7b28dad2fb80 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -1264,7 +1264,8 @@ config KUSER_HELPERS > > config COMPAT_VDSO > bool "Enable vDSO for 32-bit applications" > - depends on !CPU_BIG_ENDIAN && "$(CROSS_COMPILE_COMPAT)" != "" > + depends on !CPU_BIG_ENDIAN > + depends on CC_IS_CLANG && LD_IS_LLD || "$(CROSS_COMPILE_COMPAT)" != "" It works fine as is but it might be nice to add parentheses around the new condition for ease of understanding. > select GENERIC_COMPAT_VDSO > default y > help > diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile > index d24b12318f4c..376261d3791f 100644 > --- a/arch/arm64/kernel/vdso32/Makefile > +++ b/arch/arm64/kernel/vdso32/Makefile > @@ -10,18 +10,15 @@ include $(srctree)/lib/vdso/Makefile > > # Same as cc-*option, but using CC_COMPAT instead of CC > ifeq ($(CONFIG_CC_IS_CLANG), y) > -CC_COMPAT_CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) > - > CC_COMPAT ?= $(CC) > -CC_COMPAT += $(CC_COMPAT_CLANG_FLAGS) > - > -ifneq ($(LLVM),) > -LD_COMPAT ?= $(LD) > +CC_COMPAT += --target=arm-linux-gnueabi > else > -LD_COMPAT ?= $(CROSS_COMPILE_COMPAT)ld > +CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc > endif > + > +ifeq ($(CONFIG_LD_IS_LLD), y) > +LD_COMPAT ?= $(LD) > else > -CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc > LD_COMPAT ?= $(CROSS_COMPILE_COMPAT)ld > endif > > @@ -44,10 +41,6 @@ VDSO_CPPFLAGS += $(LINUXINCLUDE) > # Common C and assembly flags > # From top-level Makefile > VDSO_CAFLAGS = $(VDSO_CPPFLAGS) > -ifneq ($(shell $(CC_COMPAT) --version 2>&1 | head -n 1 | grep clang),) > -VDSO_CAFLAGS += --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) > -endif > - > VDSO_CAFLAGS += $(call cc32-option,-fno-PIE) > ifdef CONFIG_DEBUG_INFO > VDSO_CAFLAGS += -g > -- > 2.33.0.882.g93a45727a2-goog > >
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 5c7ae4c3954b..7b28dad2fb80 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1264,7 +1264,8 @@ config KUSER_HELPERS config COMPAT_VDSO bool "Enable vDSO for 32-bit applications" - depends on !CPU_BIG_ENDIAN && "$(CROSS_COMPILE_COMPAT)" != "" + depends on !CPU_BIG_ENDIAN + depends on CC_IS_CLANG && LD_IS_LLD || "$(CROSS_COMPILE_COMPAT)" != "" select GENERIC_COMPAT_VDSO default y help diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile index d24b12318f4c..376261d3791f 100644 --- a/arch/arm64/kernel/vdso32/Makefile +++ b/arch/arm64/kernel/vdso32/Makefile @@ -10,18 +10,15 @@ include $(srctree)/lib/vdso/Makefile # Same as cc-*option, but using CC_COMPAT instead of CC ifeq ($(CONFIG_CC_IS_CLANG), y) -CC_COMPAT_CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) - CC_COMPAT ?= $(CC) -CC_COMPAT += $(CC_COMPAT_CLANG_FLAGS) - -ifneq ($(LLVM),) -LD_COMPAT ?= $(LD) +CC_COMPAT += --target=arm-linux-gnueabi else -LD_COMPAT ?= $(CROSS_COMPILE_COMPAT)ld +CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc endif + +ifeq ($(CONFIG_LD_IS_LLD), y) +LD_COMPAT ?= $(LD) else -CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc LD_COMPAT ?= $(CROSS_COMPILE_COMPAT)ld endif @@ -44,10 +41,6 @@ VDSO_CPPFLAGS += $(LINUXINCLUDE) # Common C and assembly flags # From top-level Makefile VDSO_CAFLAGS = $(VDSO_CPPFLAGS) -ifneq ($(shell $(CC_COMPAT) --version 2>&1 | head -n 1 | grep clang),) -VDSO_CAFLAGS += --target=$(notdir $(CROSS_COMPILE_COMPAT:%-=%)) -endif - VDSO_CAFLAGS += $(call cc32-option,-fno-PIE) ifdef CONFIG_DEBUG_INFO VDSO_CAFLAGS += -g
Similar to commit 231ad7f409f1 ("Makefile: infer --target from ARCH for CC=clang") There really is no point in setting --target based on $CROSS_COMPILE_COMPAT for clang when the integrated assembler is being used. Allows COMPAT_VDSO to be selected without setting $CROSS_COMPILE_COMPAT when using clang and lld together. Before: $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config CONFIG_COMPAT_VDSO=y $ ARCH=arm64 make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config $ After: $ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config CONFIG_COMPAT_VDSO=y $ ARCH=arm64 make -j72 LLVM=1 defconfig $ grep CONFIG_COMPAT_VDSO .config CONFIG_COMPAT_VDSO=y Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> --- arch/arm64/Kconfig | 3 ++- arch/arm64/kernel/vdso32/Makefile | 17 +++++------------ 2 files changed, 7 insertions(+), 13 deletions(-)