Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760230Ab2HXWPb (ORCPT ); Fri, 24 Aug 2012 18:15:31 -0400 Received: from terminus.zytor.com ([198.137.202.10]:40012 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752108Ab2HXWP2 (ORCPT ); Fri, 24 Aug 2012 18:15:28 -0400 Date: Fri, 24 Aug 2012 15:15:14 -0700 From: tip-bot for Suresh Siddha Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, suresh.b.siddha@intel.com, tglx@linutronix.de, hpa@linux.intel.com, avi@redhat.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, suresh.b.siddha@intel.com, tglx@linutronix.de, hpa@linux.intel.com, avi@redhat.com In-Reply-To: <1345842782-24175-4-git-send-email-suresh.b.siddha@intel.com> References: <1345842782-24175-4-git-send-email-suresh.b.siddha@intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/fpu] x86, kvm: use kernel_fpu_begin/end() in kvm_load/ put_guest_fpu() Git-Commit-ID: 98700fa647b3572f7fa55485570ab9fc53b91d23 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Fri, 24 Aug 2012 15:15:20 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1899 Lines: 51 Commit-ID: 98700fa647b3572f7fa55485570ab9fc53b91d23 Gitweb: http://git.kernel.org/tip/98700fa647b3572f7fa55485570ab9fc53b91d23 Author: Suresh Siddha AuthorDate: Fri, 24 Aug 2012 14:12:59 -0700 Committer: H. Peter Anvin CommitDate: Fri, 24 Aug 2012 14:26:49 -0700 x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu() 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 Link: http://lkml.kernel.org/r/1345842782-24175-4-git-send-email-suresh.b.siddha@intel.com Cc: Avi Kivity Signed-off-by: H. Peter Anvin --- 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 be6d549..b92cc39 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5954,7 +5954,7 @@ 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); } @@ -5968,6 +5968,7 @@ 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); -- 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/