This is a note to let you know that I've just added the patch titled powerpc/vdso: Refactor CFLAGS for CVDSO build to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-vdso-refactor-cflags-for-cvdso-build.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 580f29b4880f364c6559caf60237a743ad33fa19 Author: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Date: Mon Sep 2 21:17:20 2024 +0200 powerpc/vdso: Refactor CFLAGS for CVDSO build [ Upstream commit a6b67eb09963af29991625862cbb4f56b85954ed ] In order to avoid two much duplication when we add new VDSO functionnalities in C like getrandom, refactor common CFLAGS. Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> Acked-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> Stable-dep-of: d677ce521334 ("powerpc/vdso: Drop -mstack-protector-guard flags in 32-bit files with clang") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/powerpc/kernel/vdso/Makefile b/arch/powerpc/kernel/vdso/Makefile index 0c7d82c270c37..5c7af93018865 100644 --- a/arch/powerpc/kernel/vdso/Makefile +++ b/arch/powerpc/kernel/vdso/Makefile @@ -10,28 +10,11 @@ obj-vdso64 = sigtramp64-64.o gettimeofday-64.o datapage-64.o cacheflush-64.o not ifneq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday-32.o += -include $(c-gettimeofday-y) - CFLAGS_vgettimeofday-32.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) - CFLAGS_vgettimeofday-32.o += $(call cc-option, -fno-stack-protector) - CFLAGS_vgettimeofday-32.o += -DDISABLE_BRANCH_PROFILING - CFLAGS_vgettimeofday-32.o += -ffreestanding -fasynchronous-unwind-tables - CFLAGS_REMOVE_vgettimeofday-32.o = $(CC_FLAGS_FTRACE) - CFLAGS_REMOVE_vgettimeofday-32.o += -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc - # This flag is supported by clang for 64-bit but not 32-bit so it will cause - # an unused command line flag warning for this file. - ifdef CONFIG_CC_IS_CLANG - CFLAGS_REMOVE_vgettimeofday-32.o += -fno-stack-clash-protection - endif - CFLAGS_vgettimeofday-64.o += -include $(c-gettimeofday-y) - CFLAGS_vgettimeofday-64.o += $(DISABLE_LATENT_ENTROPY_PLUGIN) - CFLAGS_vgettimeofday-64.o += $(call cc-option, -fno-stack-protector) - CFLAGS_vgettimeofday-64.o += -DDISABLE_BRANCH_PROFILING - CFLAGS_vgettimeofday-64.o += -ffreestanding -fasynchronous-unwind-tables - CFLAGS_REMOVE_vgettimeofday-64.o = $(CC_FLAGS_FTRACE) # Go prior to 1.16.x assumes r30 is not clobbered by any VDSO code. That used to be true # by accident when the VDSO was hand-written asm code, but may not be now that the VDSO is # compiler generated. To avoid breaking Go tell GCC not to use r30. Impact on code # generation is minimal, it will just use r29 instead. - CFLAGS_vgettimeofday-64.o += $(call cc-option, -ffixed-r30) + CFLAGS_vgettimeofday-64.o += -include $(c-gettimeofday-y) $(call cc-option, -ffixed-r30) endif # Build rules @@ -54,6 +37,11 @@ KASAN_SANITIZE := n KCSAN_SANITIZE := n ccflags-y := -fno-common -fno-builtin +ccflags-y += $(DISABLE_LATENT_ENTROPY_PLUGIN) +ccflags-y += $(call cc-option, -fno-stack-protector) +ccflags-y += -DDISABLE_BRANCH_PROFILING +ccflags-y += -ffreestanding -fasynchronous-unwind-tables +ccflags-remove-y := $(CC_FLAGS_FTRACE) ldflags-y := -Wl,--hash-style=both -nostdlib -shared -z noexecstack $(CLANG_FLAGS) ldflags-$(CONFIG_LD_IS_LLD) += $(call cc-option,--ld-path=$(LD),-fuse-ld=lld) ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL) @@ -62,6 +50,12 @@ ldflags-$(CONFIG_LD_ORPHAN_WARN) += -Wl,--orphan-handling=$(CONFIG_LD_ORPHAN_WAR ldflags-y += $(filter-out $(CC_AUTO_VAR_INIT_ZERO_ENABLER) $(CC_FLAGS_FTRACE) -Wa$(comma)%, $(KBUILD_CFLAGS)) CC32FLAGS := -m32 +CC32FLAGSREMOVE := -mcmodel=medium -mabi=elfv1 -mabi=elfv2 -mcall-aixdesc + # This flag is supported by clang for 64-bit but not 32-bit so it will cause + # an unused command line flag warning for this file. +ifdef CONFIG_CC_IS_CLANG +CC32FLAGSREMOVE += -fno-stack-clash-protection +endif LD32FLAGS := -Wl,-soname=linux-vdso32.so.1 AS32FLAGS := -D__VDSO32__ @@ -108,7 +102,7 @@ quiet_cmd_vdso32ld_and_check = VDSO32L $@ quiet_cmd_vdso32as = VDSO32A $@ cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) $(AS32FLAGS) -c -o $@ $< quiet_cmd_vdso32cc = VDSO32C $@ - cmd_vdso32cc = $(VDSOCC) $(c_flags) $(CC32FLAGS) -c -o $@ $< + cmd_vdso32cc = $(VDSOCC) $(filter-out $(CC32FLAGSREMOVE), $(c_flags)) $(CC32FLAGS) -c -o $@ $< quiet_cmd_vdso64ld_and_check = VDSO64L $@ cmd_vdso64ld_and_check = $(VDSOCC) $(ldflags-y) $(LD64FLAGS) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^); $(cmd_vdso_check)