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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,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 CC3B7C43381 for ; Fri, 15 Mar 2019 10:33:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1F9821872 for ; Fri, 15 Mar 2019 10:33:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728871AbfCOKdl convert rfc822-to-8bit (ORCPT ); Fri, 15 Mar 2019 06:33:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55488 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727201AbfCOKdk (ORCPT ); Fri, 15 Mar 2019 06:33:40 -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 69CE440F4F; Fri, 15 Mar 2019 10:33:40 +0000 (UTC) Received: from gondolin (dhcp-192-222.str.redhat.com [10.33.192.222]) by smtp.corp.redhat.com (Postfix) with ESMTP id 723215D6A6; Fri, 15 Mar 2019 10:33:32 +0000 (UTC) Date: Fri, 15 Mar 2019 11:33:30 +0100 From: Cornelia Huck To: Pierre Morel Cc: borntraeger@de.ibm.com, alex.williamson@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, frankja@linux.ibm.com, akrowiak@linux.ibm.com, pasic@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, freude@linux.ibm.com, mimu@linux.ibm.com Subject: Re: [PATCH v5 2/7] s390: ap: new vfio_ap_queue structure Message-ID: <20190315113330.5ef0eeef.cohuck@redhat.com> In-Reply-To: <1552493104-30510-3-git-send-email-pmorel@linux.ibm.com> References: <1552493104-30510-1-git-send-email-pmorel@linux.ibm.com> <1552493104-30510-3-git-send-email-pmorel@linux.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT 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 [10.5.110.30]); Fri, 15 Mar 2019 10:33:40 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 13 Mar 2019 17:04:59 +0100 Pierre Morel wrote: > diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c > index e9824c3..df6f21a 100644 > --- a/drivers/s390/crypto/vfio_ap_drv.c > +++ b/drivers/s390/crypto/vfio_ap_drv.c > @@ -40,14 +40,42 @@ static struct ap_device_id ap_queue_ids[] = { > > MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids); > > +/** > + * vfio_ap_queue_dev_probe: > + * > + * Allocate a vfio_ap_queue structure and associate it > + * with the device as driver_data. > + */ > static int vfio_ap_queue_dev_probe(struct ap_device *apdev) > { > + struct vfio_ap_queue *q; > + > + q = kzalloc(sizeof(*q), GFP_KERNEL); > + if (!q) > + return -ENOMEM; > + dev_set_drvdata(&apdev->device, q); > + q->apqn = to_ap_queue(&apdev->device)->qid; > + INIT_LIST_HEAD(&q->list); > + mutex_lock(&matrix_dev->lock); > + list_add(&q->list, &matrix_dev->free_list); > + mutex_unlock(&matrix_dev->lock); >From what I can see, dealing with the free_list is supposed to be protected by the matrix_dev mutex, and at a glance, it indeed seems to be held every time you interact with the list. I think it would be good to document that with a comment. (I have not reviewed this deeply, and I won't be able to look at this more until April, sorry.) > return 0; > }