From nobody Mon Feb 9 01:22:45 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1504880784022354.2841856154681; Fri, 8 Sep 2017 07:26:24 -0700 (PDT) Received: from localhost ([::1]:45702 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dqKEg-0004T6-MB for importer@patchew.org; Fri, 08 Sep 2017 10:26:22 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49142) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dqK81-0006lQ-9d for qemu-devel@nongnu.org; Fri, 08 Sep 2017 10:19:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dqK7x-000550-DD for qemu-devel@nongnu.org; Fri, 08 Sep 2017 10:19:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59002) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dqK7x-000549-6S for qemu-devel@nongnu.org; Fri, 08 Sep 2017 10:19:25 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 40BF7883D9; Fri, 8 Sep 2017 14:19:24 +0000 (UTC) Received: from redhat.com (ovpn-120-144.rdu2.redhat.com [10.10.120.144]) by smtp.corp.redhat.com (Postfix) with SMTP id 14DAA627DF; Fri, 8 Sep 2017 14:19:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 40BF7883D9 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=mst@redhat.com Date: Fri, 8 Sep 2017 17:19:19 +0300 From: "Michael S. Tsirkin" To: qemu-devel@nongnu.org Message-ID: <1504880304-12069-11-git-send-email-mst@redhat.com> References: <1504880304-12069-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1504880304-12069-1-git-send-email-mst@redhat.com> X-Mutt-Fcc: =sent X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 08 Sep 2017 14:19:24 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 10/17] intel_iommu: fix missing BQL in pt fast path X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Eduardo Habkost , Jason Wang , Peter Xu , Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Peter Xu In vtd_switch_address_space() we did the memory region switch, however it's possible that the caller of it has not taken the BQL at all. Make sure we have it. CC: Paolo Bonzini CC: Jason Wang CC: Michael S. Tsirkin Signed-off-by: Peter Xu Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/i386/intel_iommu.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c index a7bf87a..3a5bb0b 100644 --- a/hw/i386/intel_iommu.c +++ b/hw/i386/intel_iommu.c @@ -957,6 +957,8 @@ static bool vtd_dev_pt_enabled(VTDAddressSpace *as) static bool vtd_switch_address_space(VTDAddressSpace *as) { bool use_iommu; + /* Whether we need to take the BQL on our own */ + bool take_bql =3D !qemu_mutex_iothread_locked(); =20 assert(as); =20 @@ -967,6 +969,15 @@ static bool vtd_switch_address_space(VTDAddressSpace *= as) VTD_PCI_FUNC(as->devfn), use_iommu); =20 + /* + * It's possible that we reach here without BQL, e.g., when called + * from vtd_pt_enable_fast_path(). However the memory APIs need + * it. We'd better make sure we have had it already, or, take it. + */ + if (take_bql) { + qemu_mutex_lock_iothread(); + } + /* Turn off first then on the other */ if (use_iommu) { memory_region_set_enabled(&as->sys_alias, false); @@ -976,6 +987,10 @@ static bool vtd_switch_address_space(VTDAddressSpace *= as) memory_region_set_enabled(&as->sys_alias, true); } =20 + if (take_bql) { + qemu_mutex_unlock_iothread(); + } + return use_iommu; } =20 --=20 MST