From mboxrd@z Thu Jan 1 00:00:00 1970 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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 08AE2C43381 for ; Mon, 4 Mar 2019 13:28:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D46EA208E4 for ; Mon, 4 Mar 2019 13:28:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726872AbfCDN2p (ORCPT ); Mon, 4 Mar 2019 08:28:45 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42380 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726186AbfCDN2o (ORCPT ); Mon, 4 Mar 2019 08:28:44 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 83ED53082E6A; Mon, 4 Mar 2019 13:28:44 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 730685D9CA; Mon, 4 Mar 2019 13:28:44 +0000 (UTC) Received: from zmail21.collab.prod.int.phx2.redhat.com (zmail21.collab.prod.int.phx2.redhat.com [10.5.83.24]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 5DF493FB10; Mon, 4 Mar 2019 13:28:44 +0000 (UTC) Date: Mon, 4 Mar 2019 08:28:44 -0500 (EST) From: Pankaj Gupta To: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org Cc: amit@kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org, mst@redhat.com, xiaohli@redhat.com, Gal Hammer Message-ID: <50743754.9007443.1551706124243.JavaMail.zimbra@redhat.com> In-Reply-To: <20190304130511.14450-1-pagupta@redhat.com> References: <20190304130511.14450-1-pagupta@redhat.com> Subject: Re: [PATCH] virtio_console: free unused buffers with virtio port MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.116.187, 10.4.195.25] Thread-Topic: virtio_console: free unused buffers with virtio port Thread-Index: ZAH3uJ1zSiTXVyemOaDMFn8IcxOfmg== X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Mon, 04 Mar 2019 13:28:44 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Adding Gal in CC [Forgot to add] > > The commit a7a69ec0d8e4 ("virtio_console: free buffers after reset") > deffered detaching of unused buffer to virtio device unplug time. > > This causes unplug/replug of single port in virtio device with an > error "Error allocating inbufs\n". As we don't free the unused buffers > attached with the port. Re-plug the same port tries to allocate new > buffers in virtqueue and results in this error if queue is full. > > This patch removes the unused buffers in vq's when we unplug the port. > This is the best we can do as we cannot call device_reset because virtio > device is still active. This was the working behaviour before the change > introduced in commit b3258ff1d6. > > Reported-by: Xiaohui Li > Fixes: b3258ff1d6 ("virtio_console: free buffers after reset") > Signed-off-by: Pankaj Gupta > --- > drivers/char/virtio_console.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c > index fbeb71953526..5fbf2ac73111 100644 > --- a/drivers/char/virtio_console.c > +++ b/drivers/char/virtio_console.c > @@ -1506,15 +1506,25 @@ static void remove_port(struct kref *kref) > kfree(port); > } > > +static void remove_unused_bufs(struct virtqueue *vq) > +{ > + struct port_buffer *buf; > + > + while ((buf = virtqueue_detach_unused_buf(vq))) > + free_buf(buf, true); > +} > + > static void remove_port_data(struct port *port) > { > spin_lock_irq(&port->inbuf_lock); > /* Remove unused data this port might have received. */ > discard_port_data(port); > + remove_unused_bufs(port->in_vq); > spin_unlock_irq(&port->inbuf_lock); > > spin_lock_irq(&port->outvq_lock); > reclaim_consumed_buffers(port); > + remove_unused_bufs(port->out_vq); > spin_unlock_irq(&port->outvq_lock); > } > > @@ -1950,11 +1960,9 @@ static void remove_vqs(struct ports_device *portdev) > struct virtqueue *vq; > > virtio_device_for_each_vq(portdev->vdev, vq) { > - struct port_buffer *buf; > > flush_bufs(vq, true); > - while ((buf = virtqueue_detach_unused_buf(vq))) > - free_buf(buf, true); > + remove_unused_bufs(vq); > } > portdev->vdev->config->del_vqs(portdev->vdev); > kfree(portdev->in_vqs); > -- > 2.20.1 > >