From patchwork Wed Nov 22 12:18:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 13464678 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=xen.org header.i=@xen.org header.b="qH12veQX" Received: from mail.xenproject.org (mail.xenproject.org [104.130.215.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7791D51; Wed, 22 Nov 2023 04:19:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-Id:Date:Subject:To:From; bh=ptFuN2jCQTukRrWUGFV9UbE6tldJktPz8nHhLhWjreU=; b=qH12veQXrXcPAFcXs6FWQIX7Vw AkcRTjkSZ0DYJNC/lXl01AN44qiGIjdod6LdNxJMeMtjQz6IaZQbb2tvNy3VZdV5+TADd1QtIADjr WgaxrG0HIs7AfV3Gswd/9RE3vDGmoPRaFJudetxKZv2CzCTcWxUcj4hTn8dvusiUdTgg=; Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1r5mCT-0004x5-BZ; Wed, 22 Nov 2023 12:19:25 +0000 Received: from 54-240-197-231.amazon.com ([54.240.197.231] helo=REM-PW02S00X.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1r5mCT-0004y9-2b; Wed, 22 Nov 2023 12:19:25 +0000 From: Paul Durrant To: David Woodhouse , Paul Durrant , Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v9 03/15] KVM: xen: mark guest pages dirty with the pfncache lock held Date: Wed, 22 Nov 2023 12:18:10 +0000 Message-Id: <20231122121822.1042-4-paul@xen.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231122121822.1042-1-paul@xen.org> References: <20231122121822.1042-1-paul@xen.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Paul Durrant Sampling gpa and memslot from an unlocked pfncache may yield inconsistent values so, since there is no problem with calling mark_page_dirty_in_slot() with the pfncache lock held, relocate the calls in kvm_xen_update_runstate_guest() and kvm_xen_inject_pending_events() accordingly. Signed-off-by: Paul Durrant Reviewed-by: David Woodhouse --- Cc: Sean Christopherson Cc: Paolo Bonzini Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: "H. Peter Anvin" Cc: David Woodhouse Cc: x86@kernel.org v8: - New in this version. --- arch/x86/kvm/xen.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index e53fad915a62..426306022c2f 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -452,14 +452,13 @@ static void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, bool atomic) smp_wmb(); } - if (user_len2) + if (user_len2) { + mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT); read_unlock(&gpc2->lock); - - read_unlock_irqrestore(&gpc1->lock, flags); + } mark_page_dirty_in_slot(v->kvm, gpc1->memslot, gpc1->gpa >> PAGE_SHIFT); - if (user_len2) - mark_page_dirty_in_slot(v->kvm, gpc2->memslot, gpc2->gpa >> PAGE_SHIFT); + read_unlock_irqrestore(&gpc1->lock, flags); } void kvm_xen_update_runstate(struct kvm_vcpu *v, int state) @@ -565,13 +564,13 @@ void kvm_xen_inject_pending_events(struct kvm_vcpu *v) : "0" (evtchn_pending_sel32)); WRITE_ONCE(vi->evtchn_upcall_pending, 1); } + + mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT); read_unlock_irqrestore(&gpc->lock, flags); /* For the per-vCPU lapic vector, deliver it as MSI. */ if (v->arch.xen.upcall_vector) kvm_xen_inject_vcpu_vector(v); - - mark_page_dirty_in_slot(v->kvm, gpc->memslot, gpc->gpa >> PAGE_SHIFT); } int __kvm_xen_has_interrupt(struct kvm_vcpu *v)