Commit 9528d418 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'x86_urgent_for_v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 fixes from Borislav Petkov:

 - Mark serialize() noinstr so that it can be used from instrumentation-
   free code

 - Make sure FRED's RSP0 MSR is synchronized with its corresponding
   per-CPU value in order to avoid double faults in hotplug scenarios

 - Disable EXECMEM_ROX on x86 for now because it didn't receive proper
   x86 maintainers review, went in and broke a bunch of things

* tag 'x86_urgent_for_v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asm: Make serialize() always_inline
  x86/fred: Fix the FRED RSP0 MSR out of sync with its per-CPU cache
  x86: Disable EXECMEM_ROX support
parents 25144ea3 ae02ae16

arch/x86/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -83,7 +83,6 @@ config X86 
	select ARCH_HAS_DMA_OPS			if GART_IOMMU || XEN

	select ARCH_HAS_EARLY_DEBUG		if KGDB

	select ARCH_HAS_ELF_RANDOMIZE

	select ARCH_HAS_EXECMEM_ROX		if X86_64

	select ARCH_HAS_FAST_MULTIPLIER

	select ARCH_HAS_FORTIFY_SOURCE

	select ARCH_HAS_GCOV_PROFILE_ALL

arch/x86/include/asm/special_insns.h

+1 −1
Original line number Diff line number Diff line
@@ -217,7 +217,7 @@ static inline int write_user_shstk_64(u64 __user *addr, u64 val) 


#define nop() asm volatile ("nop")



static inline void serialize(void)

static __always_inline void serialize(void)

{

	/* Instruction opcode for SERIALIZE; supported in binutils >= 2.35. */

	asm volatile(".byte 0xf, 0x1, 0xe8" ::: "memory");

arch/x86/kernel/fred.c

+7 −1
Original line number Diff line number Diff line
@@ -50,7 +50,13 @@ void cpu_init_fred_exceptions(void) 
	       FRED_CONFIG_ENTRYPOINT(asm_fred_entrypoint_user));



	wrmsrl(MSR_IA32_FRED_STKLVLS, 0);

	wrmsrl(MSR_IA32_FRED_RSP0, 0);



	/*

	 * Ater a CPU offline/online cycle, the FRED RSP0 MSR should be

	 * resynchronized with its per-CPU cache.

	 */

	wrmsrl(MSR_IA32_FRED_RSP0, __this_cpu_read(fred_rsp0));



	wrmsrl(MSR_IA32_FRED_RSP1, 0);

	wrmsrl(MSR_IA32_FRED_RSP2, 0);

	wrmsrl(MSR_IA32_FRED_RSP3, 0);