Commit 471ee483 authored Nov 02, 2017 by Andy Lutomirski Committed by Ingo Molnar Nov 02, 2017

x86/entry/64: Use POP instead of MOV to restore regs on NMI return



This gets rid of the last user of the old RESTORE_..._REGS infrastructure.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/652a260f17a160789bc6a41d997f98249b73e2ab.1509609304.git.luto@kernel.org


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

parent a5122106

arch/x86/entry/entry_64.S

+7 −4

Original line number	Original line	Diff line number	Diff line
	@@ -1559,11 +1559,14 @@ end_repeat_nmi:
	nmi_swapgs:		nmi_swapgs:
	SWAPGS_UNSAFE_STACK		SWAPGS_UNSAFE_STACK
	nmi_restore:		nmi_restore:
	RESTORE_EXTRA_REGS		POP_EXTRA_REGS
	RESTORE_C_REGS		POP_C_REGS

	/* Point RSP at the "iret" frame. */		/*
	REMOVE_PT_GPREGS_FROM_STACK 6*8		* Skip orig_ax and the "outermost" frame to point RSP at the "iret"
			* at the "iret" frame.
			*/
			addq $6*8, %rsp

	/*		/*
	* Clear "NMI executing". Set DF first so that we can easily		* Clear "NMI executing". Set DF first so that we can easily