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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 5FB40C4CEC4 for ; Wed, 18 Sep 2019 07:13:06 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 19C022053B for ; Wed, 18 Sep 2019 07:13:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 19C022053B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A0FCF6B027F; Wed, 18 Sep 2019 03:13:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9BF906B0280; Wed, 18 Sep 2019 03:13:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8D5AC6B0281; Wed, 18 Sep 2019 03:13:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id 6D1466B027F for ; Wed, 18 Sep 2019 03:13:05 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id 0F127180AD80A for ; Wed, 18 Sep 2019 07:13:05 +0000 (UTC) X-FDA: 75947174730.27.cook92_72305a54eca2c X-HE-Tag: cook92_72305a54eca2c X-Filterd-Recvd-Size: 6063 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Wed, 18 Sep 2019 07:13:04 +0000 (UTC) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x8I7CxGj013303 for ; Wed, 18 Sep 2019 03:13:03 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0b-001b2d01.pphosted.com with ESMTP id 2v3cj8e01b-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 18 Sep 2019 03:13:00 -0400 Received: from localhost by e06smtp01.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, 18 Sep 2019 08:12:12 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06avi18626390.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x8I7BiYT42664258 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 18 Sep 2019 07:11:44 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D5EE94C04A; Wed, 18 Sep 2019 07:12:10 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0FFE64C05A; Wed, 18 Sep 2019 07:12:09 +0000 (GMT) Received: from in.ibm.com (unknown [9.199.59.145]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Wed, 18 Sep 2019 07:12:08 +0000 (GMT) Date: Wed, 18 Sep 2019 12:42:06 +0530 From: Bharata B Rao To: Sukadev Bhattiprolu Cc: linuxppc-dev@lists.ozlabs.org, kvm-ppc@vger.kernel.org, linux-mm@kvack.org, paulus@au1.ibm.com, aneesh.kumar@linux.vnet.ibm.com, jglisse@redhat.com, linuxram@us.ibm.com, cclaudio@linux.ibm.com, hch@lst.de Subject: Re: [PATCH v8 2/8] kvmppc: Movement of pages between normal and secure memory Reply-To: bharata@linux.ibm.com References: <20190910082946.7849-1-bharata@linux.ibm.com> <20190910082946.7849-3-bharata@linux.ibm.com> <20190917233139.GB27932@us.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190917233139.GB27932@us.ibm.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-TM-AS-GCONF: 00 x-cbid: 19091807-4275-0000-0000-00000367EA5F X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19091807-4276-0000-0000-0000387A5211 Message-Id: <20190918071206.GA11675@in.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-09-18_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=728 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1909180076 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Sep 17, 2019 at 04:31:39PM -0700, Sukadev Bhattiprolu wrote: > > Minor: Can this allocation be outside the lock? I guess it would change > the order of cleanup at the end of the function. Cleanup has bitmap_clear which needs be under spinlock, so this order of setup/alloc and cleanup will keep things simple is what I felt. > > > + spin_unlock(&kvmppc_uvmem_pfn_lock); > > + > > + *rmap = uvmem_pfn | KVMPPC_RMAP_UVMEM_PFN; > > + pvt->rmap = rmap; > > + pvt->gpa = gpa; > > + pvt->lpid = lpid; > > + dpage->zone_device_data = pvt; > > + > > + get_page(dpage); > > + return dpage; > > + > > +out_unlock: > > + unlock_page(dpage); > > +out_clear: > > + bitmap_clear(kvmppc_uvmem_pfn_bitmap, uvmem_pfn - pfn_first, 1); > > Reuse variable 'bit' here? Sure. > > > +out: > > + spin_unlock(&kvmppc_uvmem_pfn_lock); > > + return NULL; > > +} > > + > > +/* > > + * Alloc a PFN from private device memory pool and copy page from normal > > + * memory to secure memory using UV_PAGE_IN uvcall. > > + */ > > +static int > > +kvmppc_svm_page_in(struct vm_area_struct *vma, unsigned long start, > > + unsigned long end, unsigned long *rmap, > > + unsigned long gpa, unsigned int lpid, > > + unsigned long page_shift) > > +{ > > + unsigned long src_pfn, dst_pfn = 0; > > + struct migrate_vma mig; > > + struct page *spage; > > + unsigned long pfn; > > + struct page *dpage; > > + int ret = 0; > > + > > + memset(&mig, 0, sizeof(mig)); > > + mig.vma = vma; > > + mig.start = start; > > + mig.end = end; > > + mig.src = &src_pfn; > > + mig.dst = &dst_pfn; > > + > > + ret = migrate_vma_setup(&mig); > > + if (ret) > > + return ret; > > + > > + spage = migrate_pfn_to_page(*mig.src); > > + pfn = *mig.src >> MIGRATE_PFN_SHIFT; > > + if (!spage || !(*mig.src & MIGRATE_PFN_MIGRATE)) { > > + ret = 0; > > Do we want to return success here (and have caller return H_SUCCESS) if > we can't find the source page? spage is NULL for zero page. In this case we return success but there is no UV_PAGE_IN involved. Absence of MIGRATE_PFN_MIGRATE indicates that the requested page can't be migrated. I haven't hit this case till now. Similar check is also present in the nouveau driver. I am not sure if this is strictly needed here. Christoph, Jason - do you know if !(*mig.src & MIGRATE_PFN_MIGRATE) check is required and if so in which cases will it be true? > > + * Fault handler callback when HV touches any page that has been > > Nit: s/callback/callback. Called / Yeah will rephrase. Regards, Bharata.