From: Andi Kleen <[email protected]> Add 64bit assembler macros to clear registers on kernel entry. Used in followon patches.
Signed-off-by: Andi Kleen <[email protected]> --- arch/x86/entry/calling.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index 45a63e00a6af..9444e7623185 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -172,6 +172,34 @@ For 32-bit we have the following conventions - kernel is built with .byte 0xf1 .endm + .macro CLEAR_R11_TO_R15 + xorq %r15, %r15 + xorq %r14, %r14 + xorq %r13, %r13 + xorq %r12, %r12 + xorq %r11, %r11 + .endm + + .macro CLEAR_R8_TO_R15 + CLEAR_R11_TO_R15 + xorq %r10, %r10 + xorq %r9, %r9 + xorq %r8, %r8 + .endm + + .macro CLEAR_ALL_REGS + CLEAR_R8_TO_R15 + xorl %eax, %eax + xorl %ebx, %ebx + xorl %ecx, %ecx + xorl %edx, %edx + xorl %esi, %esi + xorl %edi, %edi +#ifndef CONFIG_FRAME_POINTER + xorl %ebp, %ebp +#endif + .endm + /* * This is a sneaky trick to help the unwinder find pt_regs on the stack. The * frame pointer is replaced with an encoded pointer to pt_regs. The encoding -- 2.14.3
