From 8bb0c6a1b3b2fe92707ee6f6901bfdfc392f8cd1 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@kernel.org>
Date: Fri, 9 Dec 2016 10:24:05 -0800
Subject: [PATCH] x86/asm/32: Make sync_core() handle missing CPUID on all
 32-bit kernels

commit 1c52d859cb2d417e7216d3e56bb7fea88444cec9 upstream.

We support various non-Intel CPUs that don't have the CPUID
instruction, so the M486 test was wrong.  For now, fix it with a big
hammer: handle missing CPUID on all 32-bit CPUs.

Reported-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Matthew Whitehead <tedheadster@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: xen-devel <Xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/685bd083a7c036f7769510b6846315b17d6ba71f.1481307769.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Zhang, Ning A" <ning.a.zhang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/include/asm/processor.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index c124d6ab4bf9..86bccb4bd4dc 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -574,7 +574,7 @@ static inline void sync_core(void)
 {
 	int tmp;
 
-#ifdef CONFIG_M486
+#ifdef CONFIG_X86_32
 	/*
 	 * Do a CPUID if available, otherwise do a jump.  The jump
 	 * can conveniently enough be the jump around CPUID.