From patchwork Mon May 11 16:09:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 282994 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CF07C47255 for ; Mon, 11 May 2020 16:13:33 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0FB87205ED for ; Mon, 11 May 2020 16:13:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="DB+6pskm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0FB87205ED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:36986 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jYB3c-0007fW-7n for qemu-devel@archiver.kernel.org; Mon, 11 May 2020 12:13:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48270) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jYB0V-0002WR-9Q for qemu-devel@nongnu.org; Mon, 11 May 2020 12:10:19 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:20573 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jYB0U-0001A1-CB for qemu-devel@nongnu.org; Mon, 11 May 2020 12:10:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1589213417; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:content-type:content-type:in-reply-to:in-reply-to: references:references; bh=v6NxqcYEzK4ft0LoCoTz3Wn4loJq3RbuOWoQob7rOWk=; b=DB+6pskmGNBwJ4kAMHELhA7DnK6CC0KPu1MIcZIVI+7QHj5Kf9V5wUUxqHszsvqMLd1x9n g+deqt6tdWZsGj/tUWbWOji/h+f2gPBXLIy1JkfbOnMjbnIhUzkxHU7Fj4eJ23/VlBN0Tt a5eNs6+5uJbWLu4jiSEwIm9xq/CDde4= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-60-2kxTre3wMHuXfFizGc1jaw-1; Mon, 11 May 2020 12:10:13 -0400 X-MC-Unique: 2kxTre3wMHuXfFizGc1jaw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id ADA8B475; Mon, 11 May 2020 16:10:12 +0000 (UTC) Received: from maximlenovopc.usersys.redhat.com (unknown [10.35.206.222]) by smtp.corp.redhat.com (Postfix) with ESMTP id C746A5C1B5; Mon, 11 May 2020 16:10:10 +0000 (UTC) From: Maxim Levitsky To: qemu-devel@nongnu.org Subject: [PATCH v2 5/7] virtio-scsi: don't touch scsi devices that are not yet realized or about to be un-realized Date: Mon, 11 May 2020 19:09:49 +0300 Message-Id: <20200511160951.8733-6-mlevitsk@redhat.com> In-Reply-To: <20200511160951.8733-1-mlevitsk@redhat.com> References: <20200511160951.8733-1-mlevitsk@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.61; envelope-from=mlevitsk@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/11 03:10:56 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Fam Zheng , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Eduardo Habkost , "Michael S. Tsirkin" , Maxim Levitsky , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1812399 Suggested-by: Paolo Bonzini Signed-off-by: Maxim Levitsky --- hw/scsi/virtio-scsi.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c index b0f4a35f81..1cc1fc557c 100644 --- a/hw/scsi/virtio-scsi.c +++ b/hw/scsi/virtio-scsi.c @@ -35,13 +35,30 @@ static inline int virtio_scsi_get_lun(uint8_t *lun) static inline SCSIDevice *virtio_scsi_device_find(VirtIOSCSI *s, uint8_t *lun) { + SCSIDevice *device = NULL; + if (lun[0] != 1) { return NULL; } if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) { return NULL; } - return scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun)); + + device = scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun)); + + /* + * This function might run on the IO thread and we might race against + * main thread hot-plugging the device. + * + * We assume that as soon as .realized is set to true we can let + * the user access the device. + */ + + if (!device || !atomic_load_acquire(&device->qdev.realized)) { + return NULL; + } + + return device; } void virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq, VirtIOSCSIReq *req)