From c6f31932d0a1d2b13952f506ebc92675e2d8df80 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 25 Aug 2008 17:27:21 -0700 Subject: x86: msr: propagate errors from smp_call_function_single() Propagate error (-ENXIO) from smp_call_function_single(). These errors can happen when a CPU is unplugged while the MSR driver is open. Signed-off-by: H. Peter Anvin --- include/asm-x86/msr.h | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'include/asm-x86/msr.h') diff --git a/include/asm-x86/msr.h b/include/asm-x86/msr.h index ca110ee73f07..ad5f2decf7f7 100644 --- a/include/asm-x86/msr.h +++ b/include/asm-x86/msr.h @@ -192,19 +192,20 @@ do { \ #define write_rdtscp_aux(val) wrmsr(0xc0000103, (val), 0) #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); +int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); +int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); - int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); #else /* CONFIG_SMP */ -static inline void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) +static inline int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) { rdmsr(msr_no, *l, *h); + return 0; } -static inline void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) +static inline int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) { wrmsr(msr_no, l, h); + return 0; } static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) -- cgit v1.2.3 From 08970fc4e0385790a7b093adfaa4165a189f9eb0 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Mon, 25 Aug 2008 22:39:15 -0700 Subject: x86: msr: fix bogus return values from rdmsr_safe/wrmsr_safe Impact: bogus error codes (+other?) on x86-64 The rdmsr_safe/wrmsr_safe routines have macros for the handling of the edx:eax arguments. Those macros take a variable number of assembly arguments. This is rather inherently incompatible with using %digit-style escapes in the inline assembly; replace those with %[name]-style escapes. This fixes miscompilation on x86-64, which at the very least caused bogus return values. It is possible that this could also corrupt the return value; I am not sure. Signed-off-by: H. Peter Anvin --- include/asm-x86/msr.h | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'include/asm-x86/msr.h') diff --git a/include/asm-x86/msr.h b/include/asm-x86/msr.h index ad5f2decf7f7..2362cfda1fbc 100644 --- a/include/asm-x86/msr.h +++ b/include/asm-x86/msr.h @@ -52,14 +52,14 @@ static inline unsigned long long native_read_msr_safe(unsigned int msr, { DECLARE_ARGS(val, low, high); - asm volatile("2: rdmsr ; xor %0,%0\n" + asm volatile("2: rdmsr ; xor %[err],%[err]\n" "1:\n\t" ".section .fixup,\"ax\"\n\t" - "3: mov %3,%0 ; jmp 1b\n\t" + "3: mov %[fault],%[err] ; jmp 1b\n\t" ".previous\n\t" _ASM_EXTABLE(2b, 3b) - : "=r" (*err), EAX_EDX_RET(val, low, high) - : "c" (msr), "i" (-EFAULT)); + : [err] "=r" (*err), EAX_EDX_RET(val, low, high) + : "c" (msr), [fault] "i" (-EFAULT)); return EAX_EDX_VAL(val, low, high); } @@ -73,15 +73,15 @@ static inline int native_write_msr_safe(unsigned int msr, unsigned low, unsigned high) { int err; - asm volatile("2: wrmsr ; xor %0,%0\n" + asm volatile("2: wrmsr ; xor %[err],%[err]\n" "1:\n\t" ".section .fixup,\"ax\"\n\t" - "3: mov %4,%0 ; jmp 1b\n\t" + "3: mov %[fault],%[err] ; jmp 1b\n\t" ".previous\n\t" _ASM_EXTABLE(2b, 3b) - : "=a" (err) + : [err] "=a" (err) : "c" (msr), "0" (low), "d" (high), - "i" (-EFAULT) + [fault] "i" (-EFAULT) : "memory"); return err; } -- cgit v1.2.3