[PATCH] x86/MSR: Chop off lower 32-bit value

From: Borislav Petkov
Date: Sat Oct 31 2015 - 07:40:48 EST


sparse complains that the cast truncates the high bits. But here we
really do know what we're doing and we need the lower 32 bits only as
the @low argument. So make that explicit.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/include/asm/msr.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index 77d8b284e4a7..86133827c75c 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -190,7 +190,7 @@ static inline void wrmsr(unsigned msr, unsigned low, unsigned high)

static inline void wrmsrl(unsigned msr, u64 val)
{
- native_write_msr(msr, (u32)val, (u32)(val >> 32));
+ native_write_msr(msr, (u32)(val & 0xffffffffULL), (u32)(val >> 32));
}

/* wrmsr with exception handling */
--
2.3.5

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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