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From: Huaitong Han <huaitong.han@intel.com>
To: jbeulich@suse.com, andrew.cooper3@citrix.com,
	george.dunlap@eu.citrix.com, tim@xen.org, keir@xen.org
Cc: Huaitong Han <huaitong.han@intel.com>, xen-devel@lists.xen.org
Subject: [PATCH V8 1/5] x86/hvm: pkeys, disable pkeys for guests in non-paging mode
Date: Tue,  2 Feb 2016 15:35:38 +0800	[thread overview]
Message-ID: <1454398542-4815-2-git-send-email-huaitong.han@intel.com> (raw)
In-Reply-To: <1454398542-4815-1-git-send-email-huaitong.han@intel.com>

This patch disables pkeys for guest in non-paging mode, However XEN always uses
paging mode to emulate guest non-paging mode, To emulate this behavior, pkeys
needs to be manually disabled when guest switches to non-paging mode.

Signed-off-by: Huaitong Han <huaitong.han@intel.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
Changes in v7:
no changes.

 xen/arch/x86/hvm/vmx/vmx.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 04dde83..a0d51cb 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -1368,12 +1368,13 @@ static void vmx_update_guest_cr(struct vcpu *v, unsigned int cr)
         if ( !hvm_paging_enabled(v) )
         {
             /*
-             * SMEP/SMAP is disabled if CPU is in non-paging mode in hardware.
-             * However Xen always uses paging mode to emulate guest non-paging
-             * mode. To emulate this behavior, SMEP/SMAP needs to be manually
-             * disabled when guest VCPU is in non-paging mode.
+             * SMEP/SMAP/PKU is disabled if CPU is in non-paging mode in
+             * hardware. However Xen always uses paging mode to emulate guest
+             * non-paging mode. To emulate this behavior, SMEP/SMAP/PKU needs
+             * to be manually disabled when guest VCPU is in non-paging mode.
              */
-            v->arch.hvm_vcpu.hw_cr[4] &= ~(X86_CR4_SMEP | X86_CR4_SMAP);
+            v->arch.hvm_vcpu.hw_cr[4] &=
+                ~(X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE);
         }
         __vmwrite(GUEST_CR4, v->arch.hvm_vcpu.hw_cr[4]);
         break;
-- 
2.4.3

  reply	other threads:[~2016-02-02  7:35 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-02  7:35 [PATCH V8 0/5] x86/hvm: pkeys, add memory protection-key support Huaitong Han
2016-02-02  7:35 ` Huaitong Han [this message]
2016-02-02  7:35 ` [PATCH V8 2/5] x86/hvm: pkeys, add pkeys support for guest_walk_tables Huaitong Han
2016-02-03  9:43   ` Jan Beulich
2016-02-03 10:05     ` Han, Huaitong
2016-02-02  7:35 ` [PATCH V8 3/5] x86/hvm: pkeys, add xstate support for pkeys Huaitong Han
2016-02-02  7:35 ` [PATCH V8 4/5] xen/mm: Clean up pfec handling in gva_to_gfn Huaitong Han
2016-02-02  7:35 ` [PATCH V8 5/5] x86/hvm: pkeys, add pkeys support for cpuid handling Huaitong Han
2016-02-03  9:50   ` Jan Beulich
2016-02-03 10:04     ` Han, Huaitong
2016-02-03 11:05       ` Jan Beulich

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