Merge branch 'x86/msr' into x86/core, to resolve conflicts

 Conflicts:
	arch/x86/boot/startup/sme.c
	arch/x86/coco/sev/core.c
	arch/x86/kernel/fpu/core.c
	arch/x86/kernel/fpu/xstate.c

 Semantic conflict:
	arch/x86/include/asm/sev-internal.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index eef0771512de..f963848024a5 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -238,5 +238,24 @@ register unsigned long current_stack_pointer asm(_ASM_SP);
 #define _ASM_EXTABLE_FAULT(from, to)				\
 	_ASM_EXTABLE_TYPE(from, to, EX_TYPE_FAULT)
 
+/*
+ * Both i386 and x86_64 returns 64-bit values in edx:eax for certain
+ * instructions, but GCC's "A" constraint has different meanings.
+ * For i386, "A" means exactly edx:eax, while for x86_64 it
+ * means rax *or* rdx.
+ *
+ * These helpers wrapping these semantic differences save one instruction
+ * clearing the high half of 'low':
+ */
+#ifdef CONFIG_X86_64
+# define EAX_EDX_DECLARE_ARGS(val, low, high)	unsigned long low, high
+# define EAX_EDX_VAL(val, low, high)		((low) | (high) << 32)
+# define EAX_EDX_RET(val, low, high)		"=a" (low), "=d" (high)
+#else
+# define EAX_EDX_DECLARE_ARGS(val, low, high)	u64 val
+# define EAX_EDX_VAL(val, low, high)		(val)
+# define EAX_EDX_RET(val, low, high)		"=A" (val)
+#endif
+
 #endif /* __KERNEL__ */
 #endif /* _ASM_X86_ASM_H */