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-rw-r--r--arch/x86/include/asm/processor.h68
1 files changed, 2 insertions, 66 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 537c0dd4c3d4..46640a7b7c83 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -646,72 +646,6 @@ static __always_inline void cpu_relax(void)
rep_nop();
}
-/*
- * This function forces the icache and prefetched instruction stream to
- * catch up with reality in two very specific cases:
- *
- * a) Text was modified using one virtual address and is about to be executed
- * from the same physical page at a different virtual address.
- *
- * b) Text was modified on a different CPU, may subsequently be
- * executed on this CPU, and you want to make sure the new version
- * gets executed. This generally means you're calling this in a IPI.
- *
- * If you're calling this for a different reason, you're probably doing
- * it wrong.
- */
-static inline void sync_core(void)
-{
- /*
- * There are quite a few ways to do this. IRET-to-self is nice
- * because it works on every CPU, at any CPL (so it's compatible
- * with paravirtualization), and it never exits to a hypervisor.
- * The only down sides are that it's a bit slow (it seems to be
- * a bit more than 2x slower than the fastest options) and that
- * it unmasks NMIs. The "push %cs" is needed because, in
- * paravirtual environments, __KERNEL_CS may not be a valid CS
- * value when we do IRET directly.
- *
- * In case NMI unmasking or performance ever becomes a problem,
- * the next best option appears to be MOV-to-CR2 and an
- * unconditional jump. That sequence also works on all CPUs,
- * but it will fault at CPL3 (i.e. Xen PV).
- *
- * CPUID is the conventional way, but it's nasty: it doesn't
- * exist on some 486-like CPUs, and it usually exits to a
- * hypervisor.
- *
- * Like all of Linux's memory ordering operations, this is a
- * compiler barrier as well.
- */
-#ifdef CONFIG_X86_32
- asm volatile (
- "pushfl\n\t"
- "pushl %%cs\n\t"
- "pushl $1f\n\t"
- "iret\n\t"
- "1:"
- : ASM_CALL_CONSTRAINT : : "memory");
-#else
- unsigned int tmp;
-
- asm volatile (
- UNWIND_HINT_SAVE
- "mov %%ss, %0\n\t"
- "pushq %q0\n\t"
- "pushq %%rsp\n\t"
- "addq $8, (%%rsp)\n\t"
- "pushfq\n\t"
- "mov %%cs, %0\n\t"
- "pushq %q0\n\t"
- "pushq $1f\n\t"
- "iretq\n\t"
- UNWIND_HINT_RESTORE
- "1:"
- : "=&r" (tmp), ASM_CALL_CONSTRAINT : : "cc", "memory");
-#endif
-}
-
extern void select_idle_routine(const struct cpuinfo_x86 *c);
extern void amd_e400_c1e_apic_setup(void);
@@ -986,4 +920,6 @@ enum taa_mitigations {
TAA_MITIGATION_TSX_DISABLED,
};
+extern bool gds_ucode_mitigated(void);
+
#endif /* _ASM_X86_PROCESSOR_H */