@@ -3275,3 +3275,5 @@ endmenu
source "drivers/firmware/Kconfig"
source "arch/mips/kvm/Kconfig"
+
+source "arch/mips/vdso/Kconfig"
new file mode 100644
@@ -0,0 +1,18 @@
+# For the pre-R6 code in arch/mips/vdso/vdso.h for locating
+# the base address of VDSO, the linker will emit a R_MIPS_PC32
+# relocation in binutils > 2.25 but it will fail with older versions
+# because that relocation is not supported for that symbol. As a result
+# of which we are forced to disable the VDSO symbols when building
+# with < 2.25 binutils on pre-R6 kernels. For more references on why we
+# can't use other methods to get the base address of VDSO please refer to
+# the comments on that file.
+#
+# GCC (at least up to version 9.2) appears to emit function calls that make use
+# of the GOT when targeting microMIPS, which we can't use in the VDSO due to
+# the lack of relocations. As such, we disable the VDSO for microMIPS builds.
+
+config MIPS_LD_CAN_LINK_VDSO
+ def_bool LD_VERSION >= 225000000
+
+config MIPS_DISABLE_VDSO
+ def_bool CPU_MICROMIPS || (!CPU_MIPSR6 && !MIPS_LD_CAN_LINK_VDSO)
@@ -52,37 +52,11 @@ endif
CFLAGS_REMOVE_vgettimeofday.o = -pg
-DISABLE_VDSO := n
-
-#
-# For the pre-R6 code in arch/mips/vdso/vdso.h for locating
-# the base address of VDSO, the linker will emit a R_MIPS_PC32
-# relocation in binutils > 2.25 but it will fail with older versions
-# because that relocation is not supported for that symbol. As a result
-# of which we are forced to disable the VDSO symbols when building
-# with < 2.25 binutils on pre-R6 kernels. For more references on why we
-# can't use other methods to get the base address of VDSO please refer to
-# the comments on that file.
-#
-ifndef CONFIG_CPU_MIPSR6
- ifeq ($(call ld-ifversion, -lt, 225000000, y),y)
+ifdef CONFIG_MIPS_DISABLE_VDSO
+ ifndef CONFIG_MIPS_LD_CAN_LINK_VDSO
$(warning MIPS VDSO requires binutils >= 2.25)
- DISABLE_VDSO := y
endif
-endif
-
-#
-# GCC (at least up to version 9.2) appears to emit function calls that make use
-# of the GOT when targeting microMIPS, which we can't use in the VDSO due to
-# the lack of relocations. As such, we disable the VDSO for microMIPS builds.
-#
-ifdef CONFIG_CPU_MICROMIPS
- DISABLE_VDSO := y
-endif
-
-ifeq ($(DISABLE_VDSO),y)
obj-vdso-y := $(filter-out vgettimeofday.o, $(obj-vdso-y))
- ccflags-vdso += -DDISABLE_MIPS_VDSO
endif
# VDSO linker flags.
@@ -91,7 +91,7 @@ PHDRS
VERSION
{
LINUX_2.6 {
-#ifndef DISABLE_MIPS_VDSO
+#ifndef CONFIG_MIPS_DISABLE_VDSO
global:
__vdso_clock_gettime;
__vdso_gettimeofday;
After commit 9553d16fa671 ("init/kconfig: Add LD_VERSION Kconfig"), we have access to GNU ld's version at configuration time. As a result, we can make it clearer under what configuration circumstances the MIPS VDSO needs to be disabled. This is a prerequisite for getting rid of the MIPS VDSO binutils warning and linking the VDSO when LD is ld.lld. Wrapping the call to ld-ifversion with CONFIG_LD_IS_LLD does not work because the config values are wiped away during 'make clean'. Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> --- v2 -> v3: * Fix CONFIG macro in arch/mips/vdso/vdso.lds.S, thanks to Sedat for catching it. v1 -> v2: * New patch. arch/mips/Kconfig | 2 ++ arch/mips/vdso/Kconfig | 18 ++++++++++++++++++ arch/mips/vdso/Makefile | 30 ++---------------------------- arch/mips/vdso/vdso.lds.S | 2 +- 4 files changed, 23 insertions(+), 29 deletions(-) create mode 100644 arch/mips/vdso/Kconfig