From 7524a9e41d39d989ca198415d0e089ead798667e Mon Sep 17 00:00:00 2001
From: Talons Lee <xin.li@citrix.com>
Date: Mon, 10 Dec 2018 18:03:00 +0800
Subject: always clear the X2APIC_ENABLE bit for PV guest

[ Upstream commit 5268c8f39e0efef81af2aaed160272d9eb507beb ]

Commit e657fcc clears cpu capability bit instead of using fake cpuid
value, the EXTD should always be off for PV guest without depending
on cpuid value. So remove the cpuid check in xen_read_msr_safe() to
always clear the X2APIC_ENABLE bit.

Signed-off-by: Talons Lee <xin.li@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/x86/xen/enlighten_pv.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 2f6787fc71066..c54a493e139a7 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -898,10 +898,7 @@ static u64 xen_read_msr_safe(unsigned int msr, int *err)
 	val = native_read_msr_safe(msr, err);
 	switch (msr) {
 	case MSR_IA32_APICBASE:
-#ifdef CONFIG_X86_X2APIC
-		if (!(cpuid_ecx(1) & (1 << (X86_FEATURE_X2APIC & 31))))
-#endif
-			val &= ~X2APIC_ENABLE;
+		val &= ~X2APIC_ENABLE;
 		break;
 	}
 	return val;
-- 
2.19.1