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Message-Id: <200712311349.28081.vapier@gentoo.org>
Date: Mon, 31 Dec 2007 13:49:27 -0500
From: Mike Frysinger <vapier@...too.org>
To: "H. Peter Anvin" <hpa@...or.com>
Cc: Andi Kleen <andi@...stfloor.org>, tglx@...utronix.de,
mingo@...hat.com, LKML <linux-kernel@...r.kernel.org>
Subject: Re: asm-x86/msr.h for sanitized headers: clean it or punt it
Use __asm__ and __volatile__ in code that is exported to userspace. Wrap
kernel functions with __KERNEL__ so they get scrubbed.
Signed-off-by: Mike Frysinger <vapier@...too.org>
---
diff --git a/include/asm-x86/msr.h b/include/asm-x86/msr.h
index ba4b314..664a2fa 100644
--- a/include/asm-x86/msr.h
+++ b/include/asm-x86/msr.h
@@ -191,38 +191,6 @@ static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
#define wrmsrl(msr,val) wrmsr(msr,(__u32)((__u64)(val)),((__u64)(val))>>32)
-/* wrmsr with exception handling */
-#define wrmsr_safe(msr,a,b) ({ int ret__; \
- asm volatile("2: wrmsr ; xorl %0,%0\n" \
- "1:\n\t" \
- ".section .fixup,\"ax\"\n\t" \
- "3: movl %4,%0 ; jmp 1b\n\t" \
- ".previous\n\t" \
- ".section __ex_table,\"a\"\n" \
- " .align 8\n\t" \
- " .quad 2b,3b\n\t" \
- ".previous" \
- : "=a" (ret__) \
- : "c" (msr), "0" (a), "d" (b), "i" (-EFAULT)); \
- ret__; })
-
-#define checking_wrmsrl(msr,val) wrmsr_safe(msr,(u32)(val),(u32)((val)>>32))
-
-#define rdmsr_safe(msr,a,b) \
- ({ int ret__; \
- asm volatile ("1: rdmsr\n" \
- "2:\n" \
- ".section .fixup,\"ax\"\n" \
- "3: movl %4,%0\n" \
- " jmp 2b\n" \
- ".previous\n" \
- ".section __ex_table,\"a\"\n" \
- " .align 8\n" \
- " .quad 1b,3b\n" \
- ".previous":"=&bDS" (ret__), "=a"(*(a)), "=d"(*(b)) \
- :"c"(msr), "i"(-EIO), "0"(0)); \
- ret__; })
-
#define rdtsc(low,high) \
__asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))
@@ -230,17 +198,17 @@ static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
__asm__ __volatile__ ("rdtsc" : "=a" (low) : : "edx")
#define rdtscp(low,high,aux) \
- asm volatile (".byte 0x0f,0x01,0xf9" : "=a" (low), "=d" (high), "=c" (aux))
+ __asm__ __volatile__ (".byte 0x0f,0x01,0xf9" : "=a" (low), "=d" (high), "=c" (aux))
#define rdtscll(val) do { \
unsigned int __a,__d; \
- asm volatile("rdtsc" : "=a" (__a), "=d" (__d)); \
+ __asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
(val) = ((unsigned long)__a) | (((unsigned long)__d)<<32); \
} while(0)
#define rdtscpll(val, aux) do { \
unsigned long __a, __d; \
- asm volatile (".byte 0x0f,0x01,0xf9" : "=a" (__a), "=d" (__d), "=c" (aux)); \
+ __asm__ __volatile__ (".byte 0x0f,0x01,0xf9" : "=a" (__a), "=d" (__d), "=c" (aux)); \
(val) = (__d << 32) | __a; \
} while (0)
@@ -253,6 +221,7 @@ static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
: "=a" (low), "=d" (high) \
: "c" (counter))
+
static inline void cpuid(int op, unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
@@ -320,6 +289,40 @@ static inline unsigned int cpuid_edx(unsigned int op)
return edx;
}
+#ifdef __KERNEL__
+
+/* wrmsr with exception handling */
+#define wrmsr_safe(msr,a,b) ({ int ret__; \
+ asm volatile("2: wrmsr ; xorl %0,%0\n" \
+ "1:\n\t" \
+ ".section .fixup,\"ax\"\n\t" \
+ "3: movl %4,%0 ; jmp 1b\n\t" \
+ ".previous\n\t" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 8\n\t" \
+ " .quad 2b,3b\n\t" \
+ ".previous" \
+ : "=a" (ret__) \
+ : "c" (msr), "0" (a), "d" (b), "i" (-EFAULT)); \
+ ret__; })
+
+#define checking_wrmsrl(msr,val) wrmsr_safe(msr,(u32)(val),(u32)((val)>>32))
+
+#define rdmsr_safe(msr,a,b) \
+ ({ int ret__; \
+ asm volatile ("1: rdmsr\n" \
+ "2:\n" \
+ ".section .fixup,\"ax\"\n" \
+ "3: movl %4,%0\n" \
+ " jmp 2b\n" \
+ ".previous\n" \
+ ".section __ex_table,\"a\"\n" \
+ " .align 8\n" \
+ " .quad 1b,3b\n" \
+ ".previous":"=&bDS" (ret__), "=a"(*(a)), "=d"(*(b)) \
+ :"c"(msr), "i"(-EIO), "0"(0)); \
+ ret__; })
+
#ifdef CONFIG_SMP
void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
@@ -343,6 +346,7 @@ static inline int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
return wrmsr_safe(msr_no, l, h);
}
#endif /* CONFIG_SMP */
+#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
#endif /* !__i386__ */
--
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