Re: [RFC PATCH 19/35] subarch support for control register accesses

[Chris Wright]

* Zachary Amsden (zach@xxxxxxxxxx) wrote:
> Chris Wright wrote:
> >+#define read_cr4_safe() ({			      \
> >+	unsigned int __dummy;			      \
> >+	/* This could fault if %cr4 does not exist */ \
> >+	__asm__("1: movl %%cr4, %0		\n"   \
> >+		"2:				\n"   \
> >+		".section __ex_table,\"a\"	\n"   \
> >+		".long 1b,2b			\n"   \
> >+		".previous			\n"   \
> >+		: "=r" (__dummy): "0" (0));	      \
> >+	__dummy;				      \
> >+})
> 
> I think you'll find trap and emulate quite sufficient for this one.

Heh ;-)

> >+#define stts() write_cr0(8 | read_cr0())
> >  
> 
> Nit: You shouldn't need to redefine stts() in the subarch.

Yes, you're right, better to keep things consolidated.
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