| Message ID | 20211019223646.1146945-5-ndesaulniers@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | compat vdso cleanups | expand |
On 10/20/21 12:36 AM, 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, since > commit ef94340583ee ("arm64: vdso32: drop -no-integrated-as flag"). > > 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 > > Reviewed-by: Nathan Chancellor <nathan@kernel.org> > Suggested-by: Nathan Chancellor <nathan@kernel.org> > Tested-by: Nathan Chancellor <nathan@kernel.org> > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> > --- > Changes v1 -> v2: > * Cite ef94340583ee as per Nathan. > * Add parens to Kconfig expression as per Nathan. > * Pick up Nathan's RB, TB, and SB tags. > > 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..f0f2c95aa4c8 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 e478cebb9891..c8fec493a450 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 > > @@ -45,10 +42,6 @@ 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 += $(call cc32-option,-fno-PIE) > ifdef CONFIG_DEBUG_INFO > VDSO_CAFLAGS += -g >
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 5c7ae4c3954b..f0f2c95aa4c8 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1264,7 +1264,8 @@ config KUSER_HELPERS config COMPAT_VDSO bool "Enable vDSO for 32-bit applications" - depends on !CPU_BIG_ENDIAN && "$(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 e478cebb9891..c8fec493a450 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 @@ -45,10 +42,6 @@ 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, since commit ef94340583ee ("arm64: vdso32: drop -no-integrated-as flag"). 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 Reviewed-by: Nathan Chancellor <nathan@kernel.org> Suggested-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> --- Changes v1 -> v2: * Cite ef94340583ee as per Nathan. * Add parens to Kconfig expression as per Nathan. * Pick up Nathan's RB, TB, and SB tags. arch/arm64/Kconfig | 3 ++- arch/arm64/kernel/vdso32/Makefile | 17 +++++------------ 2 files changed, 7 insertions(+), 13 deletions(-)