x86/asm/msr: Make wrmsrl() a function

As of cf991de2f614 ("x86/asm/msr: Make wrmsrl_safe() a
function"), wrmsrl_safe is a function, but wrmsrl is still a
macro.  The wrmsrl macro performs invalid shifts if the value
argument is 32 bits. This makes it unnecessarily awkward to
write code that puts an unsigned long into an MSR.

To make this work, syscall_init needs tweaking to stop passing
a function pointer to wrmsrl.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Willy Tarreau <w@1wt.eu>
Link: http://lkml.kernel.org/r/690f0c629a1085d054e2d1ef3da073cfb3f7db92.1437678821.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index c2be0375bcad..10d0596433f8 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -153,7 +153,11 @@ do {						\
 	val = paravirt_read_msr(msr, &_err);	\
 } while (0)
 
-#define wrmsrl(msr, val)	wrmsr(msr, (u32)((u64)(val)), ((u64)(val))>>32)
+static inline void wrmsrl(unsigned msr, u64 val)
+{
+	wrmsr(msr, (u32)val, (u32)(val>>32));
+}
+
 #define wrmsr_safe(msr, a, b)	paravirt_write_msr(msr, a, b)
 
 /* rdmsr with exception handling */