Commit 64ad9461 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 core updates from Borislav Petkov:

 - Get rid of all the .fixup sections because this generates
   misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
   LIVEPATCH as the backtrace misses the function which is being fixed
   up.

 - Add Straight Line Speculation mitigation support which uses a new
   compiler switch -mharden-sls= which sticks an INT3 after a RET or an
   indirect branch in order to block speculation after them. Reportedly,
   CPUs do speculate behind such insns.

 - The usual set of cleanups and improvements

* tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  x86/entry_32: Fix segment exceptions
  objtool: Remove .fixup handling
  x86: Remove .fixup section
  x86/word-at-a-time: Remove .fixup usage
  x86/usercopy: Remove .fixup usage
  x86/usercopy_32: Simplify __copy_user_intel_nocache()
  x86/sgx: Remove .fixup usage
  x86/checksum_32: Remove .fixup usage
  x86/vmx: Remove .fixup usage
  x86/kvm: Remove .fixup usage
  x86/segment: Remove .fixup usage
  x86/fpu: Remove .fixup usage
  x86/xen: Remove .fixup usage
  x86/uaccess: Remove .fixup usage
  x86/futex: Remove .fixup usage
  x86/msr: Remove .fixup usage
  x86/extable: Extend extable functionality
  x86/entry_32: Remove .fixup usage
  x86/entry_64: Remove .fixup usage
  x86/copy_mc_64: Remove .fixup usage
  ...
parents 8e5b0ade 9cdbeec4

Makefile

+0 −11
Original line number Diff line number Diff line
@@ -688,17 +688,6 @@ ifdef CONFIG_FUNCTION_TRACER 
  CC_FLAGS_FTRACE := -pg

endif



ifdef CONFIG_CC_IS_GCC

RETPOLINE_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register)

RETPOLINE_VDSO_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register)

endif

ifdef CONFIG_CC_IS_CLANG

RETPOLINE_CFLAGS	:= -mretpoline-external-thunk

RETPOLINE_VDSO_CFLAGS	:= -mretpoline

endif

export RETPOLINE_CFLAGS

export RETPOLINE_VDSO_CFLAGS



include $(srctree)/arch/$(SRCARCH)/Makefile



ifdef need-config

arch/x86/Kconfig

+13 −1
Original line number Diff line number Diff line
@@ -473,6 +473,18 @@ config RETPOLINE 
	  branches. Requires a compiler with -mindirect-branch=thunk-extern

	  support for full protection. The kernel may run slower.



config CC_HAS_SLS

	def_bool $(cc-option,-mharden-sls=all)



config SLS

	bool "Mitigate Straight-Line-Speculation"

	depends on CC_HAS_SLS && X86_64

	default n

	help

	  Compile the kernel with straight-line-speculation options to guard

	  against straight line speculation. The kernel image might be slightly

	  larger.



config X86_CPU_RESCTRL

	bool "x86 CPU resource control support"

	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
@@ -1952,7 +1964,7 @@ config EFI 


config EFI_STUB

	bool "EFI stub support"

	depends on EFI && !X86_USE_3DNOW

	depends on EFI

	depends on $(cc-option,-mabi=ms) || X86_32

	select RELOCATABLE

	help

arch/x86/Kconfig.cpu

+0 −4
Original line number Diff line number Diff line
@@ -342,10 +342,6 @@ config X86_USE_PPRO_CHECKSUM 
	def_bool y

	depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MCORE2 || MATOM



config X86_USE_3DNOW

	def_bool y

	depends on (MCYRIXIII || MK7 || MGEODE_LX) && !UML



#

# P6_NOPs are a relatively minor optimization that require a family >=

# 6 processor, except that it is broken on certain VIA chips.

arch/x86/Makefile

+16 −0
Original line number Diff line number Diff line
@@ -12,6 +12,18 @@ else 
        KBUILD_DEFCONFIG := $(ARCH)_defconfig

endif



ifdef CONFIG_CC_IS_GCC

RETPOLINE_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register)

RETPOLINE_CFLAGS	+= $(call cc-option,-mindirect-branch-cs-prefix)

RETPOLINE_VDSO_CFLAGS	:= $(call cc-option,-mindirect-branch=thunk-inline -mindirect-branch-register)

endif

ifdef CONFIG_CC_IS_CLANG

RETPOLINE_CFLAGS	:= -mretpoline-external-thunk

RETPOLINE_VDSO_CFLAGS	:= -mretpoline

endif

export RETPOLINE_CFLAGS

export RETPOLINE_VDSO_CFLAGS



# For gcc stack alignment is specified with -mpreferred-stack-boundary,

# clang has the option -mstack-alignment for that purpose.

ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
@@ -179,6 +191,10 @@ ifdef CONFIG_RETPOLINE 
  endif

endif



ifdef CONFIG_SLS

  KBUILD_CFLAGS += -mharden-sls=all

endif



KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE)



ifdef CONFIG_LTO_CLANG

arch/x86/boot/compressed/efi_thunk_64.S

+1 −1
Original line number Diff line number Diff line
@@ -101,7 +101,7 @@ SYM_FUNC_START(__efi64_thunk) 


	pop	%rbx

	pop	%rbp

	ret

	RET

SYM_FUNC_END(__efi64_thunk)



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