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Cc: akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, linux-kernel@vger.kernel.org, arei.gonglei@huawei.com, weidong.huang@huawei.com, weifuqiang@huawei.com, kvm@vger.kernel.org, linux-mm@kvack.org, Matthew Wilcox , Sean Christopherson , stable@vger.kernel.org References: <1582342427-230392-1-git-send-email-longpeng2@huawei.com> <51a25d55-de49-4c0a-c994-bf1a8cfc8638@oracle.com> <20200323160955.GY20941@ziepe.ca> <69055395-e7e5-a8e2-7f3e-f61607149318@oracle.com> <20200323180706.GC20941@ziepe.ca> <88698dd7-eb87-4b0b-7ba7-44ef6eab6a6c@oracle.com> <20200323225225.GF20941@ziepe.ca> <20200324115541.GH20941@ziepe.ca> From: Mike Kravetz Message-ID: <98d35563-8af0-2693-7e76-e6435da0bbee@oracle.com> Date: Tue, 24 Mar 2020 08:25:09 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200324115541.GH20941@ziepe.ca> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9569 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 suspectscore=0 spamscore=0 mlxlogscore=856 adultscore=0 phishscore=0 mlxscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003240085 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9569 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 clxscore=1015 lowpriorityscore=0 suspectscore=0 priorityscore=1501 malwarescore=0 mlxscore=0 adultscore=0 phishscore=0 impostorscore=0 mlxlogscore=880 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003240085 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 3/24/20 4:55 AM, Jason Gunthorpe wrote: > Also, since CH moved all the get_user_pages_fast code out of the > arch's many/all archs can drop their arch specific version of this > routine. This is really just a specialized version of gup_fast's > algorithm.. > > (also the arch versions seem different, why do some return actual > ptes, not null?) Not sure I understand that last question. The return value should be a *pte or null. /* * huge_pte_offset() - Walk the page table to resolve the hugepage * entry at address @addr * * Return: Pointer to page table or swap entry (PUD or PMD) for * address @addr, or NULL if a p*d_none() entry is encountered and the * size @sz doesn't match the hugepage size at this level of the page * table. */ -- Mike Kravetz