Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756006Ab2EDLpC (ORCPT ); Fri, 4 May 2012 07:45:02 -0400 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:35547 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755701Ab2EDLpA (ORCPT ); Fri, 4 May 2012 07:45:00 -0400 Date: Fri, 4 May 2012 17:14:49 +0530 From: Srivatsa Vaddagiri To: "Nikunj A. Dadhania" Cc: peterz@infradead.org, mingo@elte.hu, jeremy@goop.org, mtosatti@redhat.com, kvm@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, avi@redhat.com, hpa@zytor.com Subject: Re: [RFC PATCH v1 3/5] KVM: Add paravirt kvm_flush_tlb_others Message-ID: <20120504114449.GB25659@linux.vnet.ibm.com> Reply-To: Srivatsa Vaddagiri References: <20120427161727.27082.43096.stgit@abhimanyu> <20120427162401.27082.59387.stgit@abhimanyu> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20120427162401.27082.59387.stgit@abhimanyu> User-Agent: Mutt/1.5.21 (2010-09-15) x-cbid: 12050411-8256-0000-0000-0000023F6D1E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 723 Lines: 23 * Nikunj A. Dadhania [2012-04-27 21:54:37]: > @@ -1549,6 +1549,11 @@ static void kvm_set_vcpu_state(struct kvm_vcpu *vcpu) > return; > > vs->state = 1; > + if (vs->flush_on_enter) { > + kvm_mmu_flush_tlb(vcpu); > + vs->flush_on_enter = 0; > + } > + > kvm_write_guest_cached(vcpu->kvm, ghc, vs, 2*sizeof(__u32)); Reading flush_on_enter before writing ->state (=1) is racy afaics (and may cause vcpu to miss a TLB flush request). - vatsa -- 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/