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=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 39F31C04A6B for ; Wed, 8 May 2019 21:22:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1268A20850 for ; Wed, 8 May 2019 21:22:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728350AbfEHVWU (ORCPT ); Wed, 8 May 2019 17:22:20 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:57118 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726591AbfEHVWU (ORCPT ); Wed, 8 May 2019 17:22:20 -0400 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x48LLqEE081695 for ; Wed, 8 May 2019 17:22:19 -0400 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0a-001b2d01.pphosted.com with ESMTP id 2sc6pb0pd5-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 08 May 2019 17:22:19 -0400 Received: from localhost by e06smtp02.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Wed, 8 May 2019 22:22:14 +0100 Received: from b06wcsmtp001.portsmouth.uk.ibm.com (b06wcsmtp001.portsmouth.uk.ibm.com [9.149.105.160]) by b06cxnps3074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x48LMCNH55771286 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 8 May 2019 21:22:13 GMT Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E294BA405F; Wed, 8 May 2019 21:22:12 +0000 (GMT) Received: from b06wcsmtp001.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 25B42A4054; Wed, 8 May 2019 21:22:12 +0000 (GMT) Received: from oc2783563651 (unknown [9.145.71.200]) by b06wcsmtp001.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 8 May 2019 21:22:12 +0000 (GMT) Date: Wed, 8 May 2019 23:22:10 +0200 From: Halil Pasic To: Sebastian Ott Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, Cornelia Huck , Martin Schwidefsky , virtualization@lists.linux-foundation.org, "Michael S. Tsirkin" , Christoph Hellwig , Thomas Huth , Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Claudio Imbrenda , Farhan Ali , Eric Farman , Michael Mueller Subject: Re: [PATCH 05/10] s390/cio: introduce DMA pools to cio In-Reply-To: References: <20190426183245.37939-1-pasic@linux.ibm.com> <20190426183245.37939-6-pasic@linux.ibm.com> Organization: IBM X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19050821-0008-0000-0000-000002E4A9CD X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19050821-0009-0000-0000-000022512CF5 Message-Id: <20190508232210.5a555caa.pasic@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-05-08_12:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 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=8.0.1-1810050000 definitions=main-1905080129 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, 8 May 2019 15:18:10 +0200 (CEST) Sebastian Ott wrote: > > +void cio_gp_dma_free(struct gen_pool *gp_dma, void *cpu_addr, size_t size) > > +{ > > + if (!cpu_addr) > > + return; > > + memset(cpu_addr, 0, size); > > Hm, normally I'd do the memset during alloc not during free - but maybe > this makes more sense here with your usecase in mind. I allocate the backing as zeroed, and zero the memory before putting it back to the pool. So the stuff in the pool is always zeroed. > > > @@ -1063,6 +1163,7 @@ static int __init css_bus_init(void) > > unregister_reboot_notifier(&css_reboot_notifier); > > goto out_unregister; > > } > > + cio_dma_pool_init(); > > This is too late for early devices (ccw console!). You have already raised concern about this last time (thanks). I think, I've addressed this issue: tje cio_dma_pool is only used by the airq stuff. I don't think the ccw console needs it. Please have an other look at patch #6, and explain your concern in more detail if it persists. (@Mimu: What do you think, am I wrong here?) Thanks for having a look! Regards, Halil