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[PATCH v4 4/5] x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y

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Enabling CONFIG_PARAVIRT had an unintended side effect: rdmsr turned
into rdmsr_safe and wrmsr turned into wrmsr_safe, even on bare
metal.  Undo that by using the new unsafe paravirt MSR hooks.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
 arch/x86/include/asm/paravirt.h | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 68297d87e85c..0c99f10874e4 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -151,24 +151,21 @@ static inline int paravirt_write_msr_safe(unsigned msr,
 	return PVOP_CALL3(int, pv_cpu_ops.write_msr_safe, msr, low, high);
 }
 
-/* These should all do BUG_ON(_err), but our headers are too tangled. */
 #define rdmsr(msr, val1, val2)			\
 do {						\
-	int _err;				\
-	u64 _l = paravirt_read_msr_safe(msr, &_err);	\
+	u64 _l = paravirt_read_msr(msr);	\
 	val1 = (u32)_l;				\
 	val2 = _l >> 32;			\
 } while (0)
 
 #define wrmsr(msr, val1, val2)			\
 do {						\
-	paravirt_write_msr_safe(msr, val1, val2);	\
+	paravirt_write_msr(msr, val1, val2);	\
 } while (0)
 
 #define rdmsrl(msr, val)			\
 do {						\
-	int _err;				\
-	val = paravirt_read_msr_safe(msr, &_err);	\
+	val = paravirt_read_msr(msr);		\
 } while (0)
 
 static inline void wrmsrl(unsigned msr, u64 val)
-- 
2.5.0

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[PATCH v4 4/5] x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y Andy Lutomirski <luto@kernel.org> - 2016-03-12 19:10 +0100

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