From patchwork Fri Jun 8 17:48:27 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Salisbury X-Patchwork-Id: 926942 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 412VJR0hhlz9s3x; Sat, 9 Jun 2018 03:48:39 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1fRLV0-0002UO-QY; Fri, 08 Jun 2018 17:48:30 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1fRLUz-0002Ty-5B for kernel-team@lists.ubuntu.com; Fri, 08 Jun 2018 17:48:29 +0000 Received: from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1fRLUy-0004jQ-R9 for kernel-team@lists.ubuntu.com; Fri, 08 Jun 2018 17:48:28 +0000 Received: by salisbury (Postfix, from userid 1000) id B39A87E04CC; Fri, 8 Jun 2018 13:48:27 -0400 (EDT) From: Joseph Salisbury To: kernel-team@lists.ubuntu.com Subject: [SRU][Xenial][PATCH 1/1] UBUNTU: SAUCE: (no-up) virtio-scsi: Increment reqs counter. Date: Fri, 8 Jun 2018 13:48:27 -0400 Message-Id: <7e29efe861a5032a30d8975905f57ee7b33d55b5.1528464636.git.joseph.salisbury@canonical.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: References: In-Reply-To: References: X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Felipe Franciosi BugLink: http://bugs.launchpad.net/bugs/1775235 virtio-scsi itself is broken in a way that it doesn't increment the 'reqs' counter when submitting requests on MQ in certain conditions. That caused the counter to go to -1 (on the completion of the first request) and the CPU to hang indefinitely. Fixes: f1f609d8015e ("UBUNTU: SAUCE: (no-up) virtio-scsi: Fix race in target free") Signed-off-by: Felipe Franciosi Signed-off-by: Joseph Salisbury Acked-by: Stefan Bader Acked-by: Khalid Elmously --- drivers/scsi/virtio_scsi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index e2da312..b4a41d5 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -588,11 +588,12 @@ static int virtscsi_queuecommand_single(struct Scsi_Host *sh, } static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi, - struct scsi_cmnd *sc) + struct virtio_scsi_target_state *tgt, struct scsi_cmnd *sc) { u32 tag = blk_mq_unique_tag(sc->request); u16 hwq = blk_mq_unique_tag_to_hwq(tag); + atomic_inc(&tgt->reqs); return &vscsi->req_vqs[hwq]; } @@ -642,7 +643,7 @@ static int virtscsi_queuecommand_multi(struct Scsi_Host *sh, struct virtio_scsi_vq *req_vq; if (shost_use_blk_mq(sh)) - req_vq = virtscsi_pick_vq_mq(vscsi, sc); + req_vq = virtscsi_pick_vq_mq(vscsi, tgt, sc); else req_vq = virtscsi_pick_vq(vscsi, tgt);