Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/…

…git/arm64/linux

Pull arm64 fixes from Catalin Marinas:

 - Ensure that the compiler and linker versions are aligned so that ld
   doesn't complain about not understanding a .note.gnu.property section
   (emitted when pointer authentication is enabled).

 - Force -mbranch-protection=none when the feature is not enabled, in
   case a compiler may choose a different default value.

 - Remove CONFIG_DEBUG_ALIGN_RODATA. It was never in defconfig and
   rarely enabled.

 - Fix checking 16-bit Thumb-2 instructions checking mask in the
   emulation of the SETEND instruction (it could match the bottom half
   of a 32-bit Thumb-2 instruction).

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: armv8_deprecated: Fix undef_hook mask for thumb setend
  arm64: remove CONFIG_DEBUG_ALIGN_RODATA feature
  arm64: Always force a branch protection mode when the compiler has one
  arm64: Kconfig: ptrauth: Add binutils version check to fix mismatch
  init/kconfig: Add LD_VERSION Kconfig

arch/arm64/Kconfig

@@ -1502,7 +1502,10 @@ config ARM64_PTR_AUTH
 	default y
 	depends on !KVM || ARM64_VHE
 	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
-	depends on CC_IS_GCC || (CC_IS_CLANG && AS_HAS_CFI_NEGATE_RA_STATE)
+	# GCC 9.1 and later inserts a .note.gnu.property section note for PAC
+	# which is only understood by binutils starting with version 2.33.1.
+	depends on !CC_IS_GCC || GCC_VERSION < 90100 || LD_VERSION >= 233010000
+	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
 	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
 	help
 	  Pointer authentication (part of the ARMv8.3 Extensions) provides

arch/arm64/Kconfig.debug

@@ -52,19 +52,6 @@ config DEBUG_WX
 
 	  If in doubt, say "Y".
 
-config DEBUG_ALIGN_RODATA
-	depends on STRICT_KERNEL_RWX
-	bool "Align linker sections up to SECTION_SIZE"
-	help
-	  If this option is enabled, sections that may potentially be marked as
-	  read only or non-executable will be aligned up to the section size of
-	  the kernel. This prevents sections from being split into pages and
-	  avoids a potential TLB penalty. The downside is an increase in
-	  alignment and potentially wasted space. Turn on this option if
-	  performance is more important than memory pressure.
-
-	  If in doubt, say N.
-
 config DEBUG_EFI
 	depends on EFI && DEBUG_INFO
 	bool "UEFI debugging"

arch/arm64/Makefile

@@ -65,6 +65,10 @@ stack_protector_prepare: prepare0
 					include/generated/asm-offsets.h))
 endif
 
+# Ensure that if the compiler supports branch protection we default it
+# off, this will be overridden if we are using branch protection.
+branch-prot-flags-y += $(call cc-option,-mbranch-protection=none)
+
 ifeq ($(CONFIG_ARM64_PTR_AUTH),y)
 branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all
 branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf
@@ -73,9 +77,10 @@ branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pa
 # we pass it only to the assembler. This option is utilized only in case of non
 # integrated assemblers.
 branch-prot-flags-$(CONFIG_AS_HAS_PAC) += -Wa,-march=armv8.3-a
-KBUILD_CFLAGS += $(branch-prot-flags-y)
 endif
 
+KBUILD_CFLAGS += $(branch-prot-flags-y)
+
 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 KBUILD_CPPFLAGS	+= -mbig-endian
 CHECKFLAGS	+= -D__AARCH64EB__

arch/arm64/include/asm/memory.h

@@ -120,22 +120,12 @@
 
 /*
  * Alignment of kernel segments (e.g. .text, .data).
- */
-#if defined(CONFIG_DEBUG_ALIGN_RODATA)
-/*
- *  4 KB granule:   1 level 2 entry
- * 16 KB granule: 128 level 3 entries, with contiguous bit
- * 64 KB granule:  32 level 3 entries, with contiguous bit
- */
-#define SEGMENT_ALIGN		SZ_2M
-#else
-/*
+ *
  *  4 KB granule:  16 level 3 entries, with contiguous bit
  * 16 KB granule:   4 level 3 entries, without contiguous bit
  * 64 KB granule:   1 level 3 entry
  */
 #define SEGMENT_ALIGN		SZ_64K
-#endif
 
 /*
  * Memory types available.

arch/arm64/kernel/armv8_deprecated.c

@@ -601,7 +601,7 @@ static struct undef_hook setend_hooks[] = {
 	},
 	{
 		/* Thumb mode */
-		.instr_mask	= 0x0000fff7,
+		.instr_mask	= 0xfffffff7,
 		.instr_val	= 0x0000b650,
 		.pstate_mask	= (PSR_AA32_T_BIT | PSR_AA32_MODE_MASK),
 		.pstate_val	= (PSR_AA32_T_BIT | PSR_AA32_MODE_USR),

drivers/firmware/efi/libstub/arm64-stub.c

@@ -75,14 +75,12 @@ efi_status_t handle_kernel_image(unsigned long *image_addr,
 
 	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && phys_seed != 0) {
 		/*
-		 * If CONFIG_DEBUG_ALIGN_RODATA is not set, produce a
-		 * displacement in the interval [0, MIN_KIMG_ALIGN) that
-		 * doesn't violate this kernel's de-facto alignment
+		 * Produce a displacement in the interval [0, MIN_KIMG_ALIGN)
+		 * that doesn't violate this kernel's de-facto alignment
 		 * constraints.
 		 */
 		u32 mask = (MIN_KIMG_ALIGN - 1) & ~(EFI_KIMG_ALIGN - 1);
-		u32 offset = !IS_ENABLED(CONFIG_DEBUG_ALIGN_RODATA) ?
-			     (phys_seed >> 32) & mask : TEXT_OFFSET;
+		u32 offset = (phys_seed >> 32) & mask;
 
 		/*
 		 * With CONFIG_RANDOMIZE_TEXT_OFFSET=y, TEXT_OFFSET may not

init/Kconfig

@@ -16,6 +16,10 @@ config GCC_VERSION
 	default $(shell,$(srctree)/scripts/gcc-version.sh $(CC)) if CC_IS_GCC
 	default 0
 
+config LD_VERSION
+	int
+	default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh)
+
 config CC_IS_CLANG
 	def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)