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Diffstat (limited to 'arch/x86/include/asm/special_insns.h')
-rw-r--r--arch/x86/include/asm/special_insns.h57
1 files changed, 18 insertions, 39 deletions
diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h
index 2e9fc5c400cd..ecda17efa042 100644
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -10,30 +10,19 @@
#include <linux/irqflags.h>
#include <linux/jump_label.h>
-/*
- * The compiler should not reorder volatile asm statements with respect to each
- * other: they should execute in program order. However GCC 4.9.x and 5.x have
- * a bug (which was fixed in 8.1, 7.3 and 6.5) where they might reorder
- * volatile asm. The write functions are not affected since they have memory
- * clobbers preventing reordering. To prevent reads from being reordered with
- * respect to writes, use a dummy memory operand.
- */
-
-#define __FORCE_ORDER "m"(*(unsigned int *)0x1000UL)
-
void native_write_cr0(unsigned long val);
static inline unsigned long native_read_cr0(void)
{
unsigned long val;
- asm volatile("mov %%cr0,%0\n\t" : "=r" (val) : __FORCE_ORDER);
+ asm volatile("mov %%cr0,%0" : "=r" (val));
return val;
}
static __always_inline unsigned long native_read_cr2(void)
{
unsigned long val;
- asm volatile("mov %%cr2,%0\n\t" : "=r" (val) : __FORCE_ORDER);
+ asm volatile("mov %%cr2,%0" : "=r" (val));
return val;
}
@@ -42,14 +31,14 @@ static __always_inline void native_write_cr2(unsigned long val)
asm volatile("mov %0,%%cr2": : "r" (val) : "memory");
}
-static inline unsigned long __native_read_cr3(void)
+static __always_inline unsigned long __native_read_cr3(void)
{
unsigned long val;
- asm volatile("mov %%cr3,%0\n\t" : "=r" (val) : __FORCE_ORDER);
+ asm volatile("mov %%cr3,%0" : "=r" (val));
return val;
}
-static inline void native_write_cr3(unsigned long val)
+static __always_inline void native_write_cr3(unsigned long val)
{
asm volatile("mov %0,%%cr3": : "r" (val) : "memory");
}
@@ -66,10 +55,10 @@ static inline unsigned long native_read_cr4(void)
asm volatile("1: mov %%cr4, %0\n"
"2:\n"
_ASM_EXTABLE(1b, 2b)
- : "=r" (val) : "0" (0), __FORCE_ORDER);
+ : "=r" (val) : "0" (0));
#else
/* CR4 always exists on x86_64. */
- asm volatile("mov %%cr4,%0\n\t" : "=r" (val) : __FORCE_ORDER);
+ asm volatile("mov %%cr4,%0" : "=r" (val));
#endif
return val;
}
@@ -115,7 +104,7 @@ static inline void wrpkru(u32 pkru)
}
#endif
-static __always_inline void native_wbinvd(void)
+static __always_inline void wbinvd(void)
{
asm volatile("wbinvd": : :"memory");
}
@@ -167,12 +156,6 @@ static inline void __write_cr4(unsigned long x)
{
native_write_cr4(x);
}
-
-static __always_inline void wbinvd(void)
-{
- native_wbinvd();
-}
-
#endif /* CONFIG_PARAVIRT_XXL */
static __always_inline void clflush(volatile void *__p)
@@ -182,9 +165,8 @@ static __always_inline void clflush(volatile void *__p)
static inline void clflushopt(volatile void *__p)
{
- alternative_io(".byte 0x3e; clflush %P0",
- ".byte 0x66; clflush %P0",
- X86_FEATURE_CLFLUSHOPT,
+ alternative_io("ds clflush %0",
+ "clflushopt %0", X86_FEATURE_CLFLUSHOPT,
"+m" (*(volatile char __force *)__p));
}
@@ -192,22 +174,19 @@ static inline void clwb(volatile void *__p)
{
volatile struct { char x[64]; } *p = __p;
- asm volatile(ALTERNATIVE_2(
- ".byte 0x3e; clflush (%[pax])",
- ".byte 0x66; clflush (%[pax])", /* clflushopt (%%rax) */
- X86_FEATURE_CLFLUSHOPT,
- ".byte 0x66, 0x0f, 0xae, 0x30", /* clwb (%%rax) */
- X86_FEATURE_CLWB)
- : [p] "+m" (*p)
- : [pax] "a" (p));
+ asm_inline volatile(ALTERNATIVE_2(
+ "ds clflush %0",
+ "clflushopt %0", X86_FEATURE_CLFLUSHOPT,
+ "clwb %0", X86_FEATURE_CLWB)
+ : "+m" (*p));
}
#ifdef CONFIG_X86_USER_SHADOW_STACK
static inline int write_user_shstk_64(u64 __user *addr, u64 val)
{
- asm goto("1: wrussq %[val], (%[addr])\n"
+ asm goto("1: wrussq %[val], %[addr]\n"
_ASM_EXTABLE(1b, %l[fail])
- :: [addr] "r" (addr), [val] "r" (val)
+ :: [addr] "m" (*addr), [val] "r" (val)
:: fail);
return 0;
fail:
@@ -217,7 +196,7 @@ fail:
#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");