x86, paravirt: Replace GET_CR2_INTO_RCX with GET_CR2_INTO_RAX
GET_CR2_INTO_RCX is asinine: it is only used in one place, the actual
paravirt call returns the value in %rax, not %rcx; and the one place
that wants it wants the result in %r9. We actually generate as a
result of this call:
call ...
movq %rax, %rcx
xorq %rax, %rax /* this value isn't even used... */
movq %rcx, %r9
At least make the macro do what the paravirt call does, which is put
the value into %rax.
Nevermind the fact that the macro clobbers all the volatile registers.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1334794610-5546-4-git-send-email-hpa@zytor.com
Cc: Glauber de Oliveira Costa <glommer@parallels.com>
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index aa0f913..6cbbabf 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -1023,10 +1023,8 @@
call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs) \
)
-#define GET_CR2_INTO_RCX \
- call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2); \
- movq %rax, %rcx; \
- xorq %rax, %rax;
+#define GET_CR2_INTO_RAX \
+ call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2)
#define PARAVIRT_ADJUST_EXCEPTION_FRAME \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_adjust_exception_frame), \