Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760219Ab2HXVQZ (ORCPT ); Fri, 24 Aug 2012 17:16:25 -0400 Received: from mga03.intel.com ([143.182.124.21]:7595 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753783Ab2HXVPf (ORCPT ); Fri, 24 Aug 2012 17:15:35 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,304,1344236400"; d="scan'208";a="190967387" From: Suresh Siddha To: hpa@zytor.com, mingo@kernel.org, torvalds@linux-foundation.org, andreas.herrmann3@amd.com, bp@amd64.org, robert.richter@amd.com Cc: linux-kernel@vger.kernel.org, Suresh Siddha , Avi Kivity Subject: [PATCH 3/6] x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu() Date: Fri, 24 Aug 2012 14:12:59 -0700 Message-Id: <1345842782-24175-4-git-send-email-suresh.b.siddha@intel.com> X-Mailer: git-send-email 1.7.6.5 In-Reply-To: <1345842782-24175-1-git-send-email-suresh.b.siddha@intel.com> References: <1345842782-24175-1-git-send-email-suresh.b.siddha@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1379 Lines: 43 kvm's guest fpu save/restore should be wrapped around kernel_fpu_begin/end(). This will avoid for example taking a DNA in kvm_load_guest_fpu() when it tries to load the fpu immediately after doing unlazy_fpu() on the host side. More importantly this will prevent the host process fpu from being corrupted. Signed-off-by: Suresh Siddha Cc: Avi Kivity --- arch/x86/kvm/x86.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 42bce48..67e773c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5969,7 +5969,7 @@ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) */ kvm_put_guest_xcr0(vcpu); vcpu->guest_fpu_loaded = 1; - unlazy_fpu(current); + kernel_fpu_begin(); fpu_restore_checking(&vcpu->arch.guest_fpu); trace_kvm_fpu(1); } @@ -5983,6 +5983,7 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) vcpu->guest_fpu_loaded = 0; fpu_save_init(&vcpu->arch.guest_fpu); + kernel_fpu_end(); ++vcpu->stat.fpu_reload; kvm_make_request(KVM_REQ_DEACTIVATE_FPU, vcpu); trace_kvm_fpu(0); -- 1.7.6.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/