Commit a6b67eb0 authored by Christophe Leroy's avatar Christophe Leroy Committed by Jason A. Donenfeld
Browse files

powerpc/vdso: Refactor CFLAGS for CVDSO build 



In order to avoid two much duplication when we add new VDSO
functionnalities in C like getrandom, refactor common CFLAGS.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: default avatarJason A. Donenfeld <Jason@zx2c4.com>
parent b163596a

arch/powerpc/kernel/vdso/Makefile

+13 −19
Original line number Diff line number Diff line
@@ -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
@@ -49,6 +32,11 @@ targets += $(obj-vdso64) vdso64.so.dbg vgettimeofday-64.o 
obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))



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)
@@ -57,6 +45,12 @@ 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__
@@ -105,7 +99,7 @@ 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)