From c36c940cd4aab393c09d457e2414423ac92bd339 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 e40b19ca486e..353f038ec645 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -596,7 +596,7 @@ 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.