MIPS: Disable VDSO time functionality on microMIPS (07015d7a) · Commits · 戴 / test

A check we're about to add to pick up on function calls that depend on bogus use of the GOT in the VDSO picked up on instances of such function calls in microMIPS builds. Since the code appears genuinely problematic, and given the relatively small amount of use & testing that microMIPS sees, go ahead & disable the VDSO for microMIPS builds. Signed-off-by:

Paul Burton <paulburton@kernel.org>

arch/mips/vdso/Makefile

+17 −2

Original line number	Diff line number	Diff line
		@@ -52,6 +52,8 @@ 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
		@@ -65,10 +67,23 @@ CFLAGS_REMOVE_vgettimeofday.o = -pg
		ifndef CONFIG_CPU_MIPSR6
		ifeq ($(call ld-ifversion, -lt, 225000000, y),y)
		$(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
		endif

		# VDSO linker flags.
		VDSO_LDFLAGS := \

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