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=-8.4 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,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 5F4FCC1975A for ; Thu, 12 Mar 2020 23:50:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 2509C206F7 for ; Thu, 12 Mar 2020 23:50:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="Yjw6gyMW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2509C206F7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nvidia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id AA2B06B0007; Thu, 12 Mar 2020 19:50:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A05F16B0008; Thu, 12 Mar 2020 19:50:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8CD5F6B000A; Thu, 12 Mar 2020 19:50:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0123.hostedemail.com [216.40.44.123]) by kanga.kvack.org (Postfix) with ESMTP id 70ACA6B0007 for ; Thu, 12 Mar 2020 19:50:24 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 30BFA5DE5 for ; Thu, 12 Mar 2020 23:50:24 +0000 (UTC) X-FDA: 76588356768.08.act40_36e6aef2ad08 X-HE-Tag: act40_36e6aef2ad08 X-Filterd-Recvd-Size: 3839 Received: from hqnvemgate25.nvidia.com (hqnvemgate25.nvidia.com [216.228.121.64]) by imf20.hostedemail.com (Postfix) with ESMTP for ; Thu, 12 Mar 2020 23:50:23 +0000 (UTC) Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate25.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA) id ; Thu, 12 Mar 2020 16:49:36 -0700 Received: from hqmail.nvidia.com ([172.20.161.6]) by hqpgpgate101.nvidia.com (PGP Universal service); Thu, 12 Mar 2020 16:50:22 -0700 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Thu, 12 Mar 2020 16:50:22 -0700 Received: from rcampbell-dev.nvidia.com (172.20.13.39) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 12 Mar 2020 23:50:21 +0000 Subject: Re: [PATCH hmm 9/8] mm/hmm: do not check pmd_protnone twice in hmm_vma_handle_pmd() To: Jason Gunthorpe , Jerome Glisse , CC: , John Hubbard , , , "Christoph Hellwig" , Philip Yang References: <20200311183506.3997-1-jgg@ziepe.ca> <20200312193310.GA1190@ziepe.ca> X-Nvconfidentiality: public From: Ralph Campbell Message-ID: Date: Thu, 12 Mar 2020 16:50:21 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20200312193310.GA1190@ziepe.ca> X-Originating-IP: [172.20.13.39] X-ClientProxiedBy: HQMAIL107.nvidia.com (172.20.187.13) To HQMAIL107.nvidia.com (172.20.187.13) Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1584056976; bh=aQ7MGcgWWA7Gw37+lSs7CbvLiWZTO8XM95c59ZBgdKg=; h=X-PGP-Universal:Subject:To:CC:References:X-Nvconfidentiality:From: Message-ID:Date:User-Agent:MIME-Version:In-Reply-To: X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language: Content-Transfer-Encoding; b=Yjw6gyMW0BovQBnuixd3cn86pt/2gu0Ac7NS1EnrlfxR7BcgErUjUkaNBWBnWSs0C 9F/zA30YH9bMAPNXu2Nr8PI3K9ZpeUmb5sbe4/Dc+V54R0Wv6WLNsx84vq7EJwran4 gcySY5TUcmBxxGCC3Dm79KkOwpO8r+SVf9oXVGcyPMffb5pUJUU8AwjqTPQ0KOmNsF 8nccy22VR59NWO9vtEs5Uys8+6xnGlNvFd8ns+yqIJ7oor9dPe7QJG5pEmG0tR6IfW ioJqV0YRdsx0vDGo+QtSjwzFKi7XEnibWrNKLL48QDZFzbTcjsPzlozJ46kwdQlcN8 hyqUxrvZOJYFw== 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 3/12/20 12:33 PM, Jason Gunthorpe wrote: > pmd_to_hmm_pfn_flags() already checks it and makes the cpu flags 0. If no > fault is requested then the pfns should be returned with the not valid > flags. > > It should not unconditionally fault if faulting is not requested. > > Fixes: 2aee09d8c116 ("mm/hmm: change hmm_vma_fault() to allow write fault on page basis") > Signed-off-by: Jason Gunthorpe Looks good to me. Reviewed-by: Ralph Campbell > --- > mm/hmm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Bonus patch, this one got found after I made the series.. > > diff --git a/mm/hmm.c b/mm/hmm.c > index ca33d086bdc190..6d9da4b0f0a9f8 100644 > --- a/mm/hmm.c > +++ b/mm/hmm.c > @@ -226,7 +226,7 @@ static int hmm_vma_handle_pmd(struct mm_walk *walk, unsigned long addr, > hmm_range_need_fault(hmm_vma_walk, pfns, npages, cpu_flags, > &fault, &write_fault); > > - if (pmd_protnone(pmd) || fault || write_fault) > + if (fault || write_fault) > return hmm_vma_walk_hole_(addr, end, fault, write_fault, walk); > > pfn = pmd_pfn(pmd) + ((addr & ~PMD_MASK) >> PAGE_SHIFT); >