Merge tag 'gcc-minimum-version-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull compiler version requirement update from Arnd Bergmann:
 "Require gcc-8 and binutils-2.30

  x86 already uses gcc-8 as the minimum version, this changes all other
  architectures to the same version. gcc-8 is used is Debian 10 and Red
  Hat Enterprise Linux 8, both of which are still supported, and
  binutils 2.30 is the oldest corresponding version on those.

  Ubuntu Pro 18.04 and SUSE Linux Enterprise Server 15 both use gcc-7 as
  the system compiler but additionally include toolchains that remain
  supported.

  With the new minimum toolchain versions, a number of workarounds for
  older versions can be dropped, in particular on x86_64 and arm64.
  Importantly, the updated compiler version allows removing two of the
  five remaining gcc plugins, as support for sancov and structeak
  features is already included in modern compiler versions.

  I tried collecting the known changes that are possible based on the
  new toolchain version, but expect that more cleanups will be possible.

  Since this touches multiple architectures, I merged the patches
  through the asm-generic tree."

* tag 'gcc-minimum-version-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  Makefile.kcov: apply needed compiler option unconditionally in CFLAGS_KCOV
  Documentation: update binutils-2.30 version reference
  gcc-plugins: remove SANCOV gcc plugin
  Kbuild: remove structleak gcc plugin
  arm64: drop binutils version checks
  raid6: skip avx512 checks
  kbuild: require gcc-8 and binutils-2.30

6 files changed, 6 insertions, 63 deletions

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index c314eb429b9f..bcc1773fec77 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -659,9 +659,6 @@ config ARM64_ERRATUM_843419
 
 	  If unsure, say Y.
 
-config ARM64_LD_HAS_FIX_ERRATUM_843419
-	def_bool $(ld-option,--fix-cortex-a53-843419)
-
 config ARM64_ERRATUM_1024718
 	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
 	default y
@@ -1907,13 +1904,9 @@ config ARM64_PAN
 	  The feature is detected at runtime, and will remain as a 'nop'
 	  instruction if the cpu does not implement the feature.
 
-config AS_HAS_LSE_ATOMICS
-	def_bool $(as-instr,.arch_extension lse)
-
 config ARM64_LSE_ATOMICS
 	bool
 	default ARM64_USE_LSE_ATOMICS
-	depends on AS_HAS_LSE_ATOMICS
 
 config ARM64_USE_LSE_ATOMICS
 	bool "Atomic instructions"
@@ -1925,20 +1918,12 @@ config ARM64_USE_LSE_ATOMICS
 
 	  Say Y here to make use of these instructions for the in-kernel
 	  atomic routines. This incurs a small overhead on CPUs that do
-	  not support these instructions and requires the kernel to be
-	  built with binutils >= 2.25 in order for the new instructions
-	  to be used.
+	  not support these instructions.
 
 endmenu # "ARMv8.1 architectural features"
 
 menu "ARMv8.2 architectural features"
 
-config AS_HAS_ARMV8_2
-	def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
-
-config AS_HAS_SHA3
-	def_bool $(as-instr,.arch armv8.2-a+sha3)
-
 config ARM64_PMEM
 	bool "Enable support for persistent memory"
 	select ARCH_HAS_PMEM_API
@@ -2012,7 +1997,6 @@ config ARM64_PTR_AUTH_KERNEL
 	bool "Use pointer authentication for kernel"
 	default y
 	depends on ARM64_PTR_AUTH
-	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3
 	# Modern compilers insert a .note.gnu.property section note for PAC
 	# which is only understood by binutils starting with version 2.33.1.
 	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
@@ -2033,19 +2017,10 @@ config CC_HAS_BRANCH_PROT_PAC_RET
 	# GCC 9 or later, clang 8 or later
 	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
 
-config CC_HAS_SIGN_RETURN_ADDRESS
-	# GCC 7, 8
-	def_bool $(cc-option,-msign-return-address=all)
-
-config AS_HAS_ARMV8_3
-	def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
-
 config AS_HAS_CFI_NEGATE_RA_STATE
+	# binutils 2.34+
 	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
 
-config AS_HAS_LDAPR
-	def_bool $(as-instr,.arch_extension rcpc)
-
 endmenu # "ARMv8.3 architectural features"
 
 menu "ARMv8.4 architectural features"
@@ -2073,20 +2048,13 @@ config ARM64_AMU_EXTN
 	  correctly reflect reality. Most commonly, the value read will be 0,
 	  indicating that the counter is not enabled.
 
-config AS_HAS_ARMV8_4
-	def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
-
 config ARM64_TLB_RANGE
 	bool "Enable support for tlbi range feature"
 	default y
-	depends on AS_HAS_ARMV8_4
 	help
 	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
 	  range of input addresses.
 
-	  The feature introduces new assembly instructions, and they were
-	  support when binutils >= 2.30.
-
 endmenu # "ARMv8.4 architectural features"
 
 menu "ARMv8.5 architectural features"
@@ -2162,7 +2130,6 @@ config ARM64_MTE
 	default y
 	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
 	depends on AS_HAS_ARMV8_5
-	depends on AS_HAS_LSE_ATOMICS
 	# Required for tag checking in the uaccess routines
 	select ARM64_PAN
 	select ARCH_HAS_SUBPAGE_FAULTS
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 1d5dfcd1c13e..73a10f65ce8b 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -16,14 +16,11 @@ ifeq ($(CONFIG_RELOCATABLE), y)
 # Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour
 # for relative relocs, since this leads to better Image compression
 # with the relocation offsets always being zero.
-LDFLAGS_vmlinux		+= -shared -Bsymbolic -z notext \
-			$(call ld-option, --no-apply-dynamic-relocs)
+LDFLAGS_vmlinux	+= -shared -Bsymbolic -z notext --no-apply-dynamic-relocs
 endif
 
 ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
-  ifeq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y)
 LDFLAGS_vmlinux	+= --fix-cortex-a53-843419
-  endif
 endif
 
 cc_has_k_constraint := $(call try-run,echo				\
@@ -105,12 +102,8 @@ endif
 # hardware.
 ifeq ($(CONFIG_AS_HAS_ARMV8_5), y)
   asm-arch := armv8.5-a
-else ifeq ($(CONFIG_AS_HAS_ARMV8_4), y)
+else
   asm-arch := armv8.4-a
-else ifeq ($(CONFIG_AS_HAS_ARMV8_3), y)
-  asm-arch := armv8.3-a
-else ifeq ($(CONFIG_AS_HAS_ARMV8_2), y)
-  asm-arch := armv8.2-a
 endif
 
 ifdef asm-arch
@@ -201,16 +194,6 @@ install zinstall:
 
 archprepare:
 	$(Q)$(MAKE) $(build)=arch/arm64/tools kapi
-ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
-  ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y)
-	@echo "warning: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum" >&2
-  endif
-endif
-ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS),y)
-  ifneq ($(CONFIG_ARM64_LSE_ATOMICS),y)
-	@echo "warning: LSE atomics not supported by binutils" >&2
-  endif
-endif
 
 ifeq ($(KBUILD_EXTMOD),)
 # We need to generate vdso-offsets.h before compiling certain files in kernel/.
diff --git a/arch/arm64/include/asm/rwonce.h b/arch/arm64/include/asm/rwonce.h
index 56f7b1d4d54b..97d9256d33c9 100644
--- a/arch/arm64/include/asm/rwonce.h
+++ b/arch/arm64/include/asm/rwonce.h
@@ -12,16 +12,12 @@
 
 #ifndef BUILD_VDSO
 
-#ifdef CONFIG_AS_HAS_LDAPR
 #define __LOAD_RCPC(sfx, regs...)					\
 	ALTERNATIVE(							\
 		"ldar"	#sfx "\t" #regs,				\
 		".arch_extension rcpc\n"				\
 		"ldapr"	#sfx "\t" #regs,				\
 	ARM64_HAS_LDAPR)
-#else
-#define __LOAD_RCPC(sfx, regs...)	"ldar" #sfx "\t" #regs
-#endif /* CONFIG_AS_HAS_LDAPR */
 
 /*
  * When building with LTO, there is an increased risk of the compiler
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 096e45acadb2..713248f240e0 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -19,7 +19,6 @@ if VIRTUALIZATION
 
 menuconfig KVM
 	bool "Kernel-based Virtual Machine (KVM) support"
-	depends on AS_HAS_ARMV8_4
 	select KVM_COMMON
 	select KVM_GENERIC_HARDWARE_ENABLING
 	select KVM_GENERIC_MMU_NOTIFIER
diff --git a/arch/arm64/lib/xor-neon.c b/arch/arm64/lib/xor-neon.c
index f9a53b7f9842..8fffebfa17b2 100644
--- a/arch/arm64/lib/xor-neon.c
+++ b/arch/arm64/lib/xor-neon.c
@@ -319,7 +319,7 @@ static void xor_arm64_eor3_5(unsigned long bytes,
 
 static int __init xor_neon_init(void)
 {
-	if (IS_ENABLED(CONFIG_AS_HAS_SHA3) && cpu_have_named_feature(SHA3)) {
+	if (cpu_have_named_feature(SHA3)) {
 		xor_block_inner_neon.do_3 = xor_arm64_eor3_3;
 		xor_block_inner_neon.do_4 = xor_arm64_eor3_4;
 		xor_block_inner_neon.do_5 = xor_arm64_eor3_5;
diff --git a/arch/um/Makefile b/arch/um/Makefile
index 9ed792e565c9..7be0143b5ba3 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -118,9 +118,7 @@ archprepare:
 	$(Q)$(MAKE) $(build)=$(HOST_DIR)/um include/generated/user_constants.h
 
 LINK-$(CONFIG_LD_SCRIPT_STATIC) += -static
-ifdef CONFIG_LD_SCRIPT_DYN
-LINK-$(call gcc-min-version, 60100)$(CONFIG_CC_IS_CLANG) += -no-pie
-endif
+LINK-$(CONFIG_LD_SCRIPT_DYN) += -no-pie
 LINK-$(CONFIG_LD_SCRIPT_DYN_RPATH) += -Wl,-rpath,/lib
 
 CFLAGS_NO_HARDENING := $(call cc-option, -fno-PIC,) $(call cc-option, -fno-pic,) \