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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_SANE_1 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 9C7EEC432C0 for ; Thu, 28 Nov 2019 08:38:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 70AEC21741 for ; Thu, 28 Nov 2019 08:38:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="R0O4N0uw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726558AbfK1Iia (ORCPT ); Thu, 28 Nov 2019 03:38:30 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:55446 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726301AbfK1Ii3 (ORCPT ); Thu, 28 Nov 2019 03:38:29 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xAS8Y4Jo035180; Thu, 28 Nov 2019 08:37:53 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2019-08-05; bh=lT5186ZNBxR5ODA3TJnZ4mvt45f9bF6EnEE3JtOE2LE=; b=R0O4N0uwWjPVpcQSpyAxWnjbP89B8lu82n+53715BCU9EGqXDv6fQqjFsIiVsc14Q2Dq I3dKEUmacHX2yhLek9LuQUTPThKpniVbxpVGlbpJGVjjZEgtLn1i3uPdLwJxr3andgBW ReUojJrt9UDJG3gg2C6sCgQsSxYxr3YMX8RYVeO0/REFnLMhvqm1DrRlHFzHmJouISlT Zlwy4LlAyIGifexDgTLGERJ8d6FVI9LPDEWbrTI1p0vkcldyd0rkHxnAddb+7YpZk3Nr pvw9garPA7sQUxehv3JOEklYMEoD/gD7RiGc+837YO+pdh+6mcZlYrOUf4xJZc4nrFCK /w== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by userp2120.oracle.com with ESMTP id 2wewdrj27s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 28 Nov 2019 08:37:52 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xAS8YAp3167927; Thu, 28 Nov 2019 08:37:51 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userp3030.oracle.com with ESMTP id 2why49pb3s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 28 Nov 2019 08:37:51 +0000 Received: from abhmp0018.oracle.com (abhmp0018.oracle.com [141.146.116.24]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id xAS8bkFY023351; Thu, 28 Nov 2019 08:37:46 GMT Received: from kadam (/129.205.23.165) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 28 Nov 2019 00:37:45 -0800 Date: Thu, 28 Nov 2019 11:37:35 +0300 From: Dan Carpenter To: Anton Ivanov Cc: Wei Yongjun , Song Liu , Daniel Borkmann , kernel-janitors@vger.kernel.org, Richard Weinberger , Jeff Dike , linux-um@lists.infradead.org, Alexei Starovoitov , netdev@vger.kernel.org, bpf@vger.kernel.org, Martin KaFai Lau Subject: Re: [PATCH -next] um: vector: use GFP_ATOMIC under spin lock Message-ID: <20191128083735.GE1781@kadam> References: <20191128020147.191893-1-weiyongjun1@huawei.com> <20191128080641.GD1781@kadam> <5892ee7c-ff24-fb3c-6911-44e0b1d5895f@cambridgegreys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5892ee7c-ff24-fb3c-6911-44e0b1d5895f@cambridgegreys.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9454 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-1911280073 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9454 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-1911280073 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Thu, Nov 28, 2019 at 08:18:30AM +0000, Anton Ivanov wrote: > > > On 28/11/2019 08:06, Dan Carpenter wrote: > > On Thu, Nov 28, 2019 at 02:01:47AM +0000, Wei Yongjun wrote: > > > A spin lock is taken here so we should use GFP_ATOMIC. > > > > > > Fixes: 9807019a62dc ("um: Loadable BPF "Firmware" for vector drivers") > > > Signed-off-by: Wei Yongjun > > > --- > > > arch/um/drivers/vector_kern.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c > > > index 92617e16829e..6ff0065a271d 100644 > > > --- a/arch/um/drivers/vector_kern.c > > > +++ b/arch/um/drivers/vector_kern.c > > > @@ -1402,7 +1402,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev, > > > kfree(vp->bpf->filter); > > > vp->bpf->filter = NULL; > > > } else { > > > - vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_KERNEL); > > > + vp->bpf = kmalloc(sizeof(struct sock_fprog), GFP_ATOMIC); > > > if (vp->bpf == NULL) { > > > netdev_err(dev, "failed to allocate memory for firmware\n"); > > > goto flash_fail; > > > @@ -1414,7 +1414,7 @@ static int vector_net_load_bpf_flash(struct net_device *dev, > > > if (request_firmware(&fw, efl->data, &vdevice->pdev.dev)) > > ^^^^^^^^^^^^^^^^ > > > > Is it really possible to call request_firmware() while holding a > > spin_lock? I was so sure that read from the disk. > > Works, I tested the patch quite a few times. > Do you have CONFIG_DEBUG_ATOMIC_SLEEP enabled? The GFP_KERNEL calls should have triggered a warning if so. regards, dan carpenter