From: Jan Beulich <JBeulich@suse.com>
Date: Fri, 3 Feb 2017 08:58:03 +0000 (-0700)
Subject: x86/entry/32: Relax a pvops stub clobber specification
X-Git-Tag: v4.12-rc1~147^2~24
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=fdbd518adfaf2c10903250dffe70c61ed90b7dd7;p=karo-tx-linux.git

x86/entry/32: Relax a pvops stub clobber specification

The code at .Lrestore_nocheck does not make any assumptions on register
values, so all registers can be clobbered on code paths leading there.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.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/5894542B02000078001366C5@prv-mh.provo.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 57f7ec35216e..5553475f6008 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -585,7 +585,7 @@ ENTRY(iret_exc	)
 	 * will soon execute iret and the tracer was already set to
 	 * the irqstate after the IRET:
 	 */
-	DISABLE_INTERRUPTS(CLBR_EAX)
+	DISABLE_INTERRUPTS(CLBR_ANY)
 	lss	(%esp), %esp			/* switch to espfix segment */
 	jmp	.Lrestore_nocheck
 #endif