x86/entry/32: Introduce SAVE_ALL_NMI and RESTORE_ALL_NMI

joergroedel · KAGA-KOKO · commit 8b376fae0514 · 2018-07-20T01:11:38.000+02:00
These macros will be used in the NMI handler code and replace plain SAVE_ALL and RESTORE_REGS there. The NMI-specific CR3-switch will be added to these macros later. Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Pavel Machek <pavel@ucw.cz> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: linux-mm@kvack.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Waiman Long <llong@redhat.com> Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca> Cc: joro@8bytes.org Link: https://lkml.kernel.org/r/1531906876-13451-10-git-send-email-joro@8bytes.org
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
@@ -181,6 +181,9 @@
 
 .endm
 
+.macro SAVE_ALL_NMI
+	SAVE_ALL
+.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
@@ -227,6 +230,10 @@
 	POP_GS_EX
 .endm
 
+.macro RESTORE_ALL_NMI pop=0
+	RESTORE_REGS pop=\pop
+.endm
+
 .macro CHECK_AND_APPLY_ESPFIX
 #ifdef CONFIG_X86_ESPFIX32
 #define GDT_ESPFIX_SS PER_CPU_VAR(gdt_page) + (GDT_ENTRY_ESPFIX_SS * 8)
@@ -1161,7 +1168,7 @@ ENTRY(nmi)
 #endif
 
 	pushl	%eax				# pt_regs->orig_ax
-	SAVE_ALL
+	SAVE_ALL_NMI
 	ENCODE_FRAME_POINTER
 	xorl	%edx, %edx			# zero error code
 	movl	%esp, %eax			# pt_regs pointer
@@ -1189,7 +1196,7 @@ ENTRY(nmi)
 
 .Lnmi_return:
 	CHECK_AND_APPLY_ESPFIX
-	RESTORE_REGS 4
+	RESTORE_ALL_NMI pop=4
 	jmp	.Lirq_return
 
 #ifdef CONFIG_X86_ESPFIX32
@@ -1205,12 +1212,12 @@ ENTRY(nmi)
 	pushl	16(%esp)
 	.endr
 	pushl	%eax
-	SAVE_ALL
+	SAVE_ALL_NMI
 	ENCODE_FRAME_POINTER
 	FIXUP_ESPFIX_STACK			# %eax == %esp
 	xorl	%edx, %edx			# zero error code
 	call	do_nmi
-	RESTORE_REGS
+	RESTORE_ALL_NMI
 	lss	12+4(%esp), %esp		# back to espfix stack
 	jmp	.Lirq_return
 #endif
