From patchwork Mon Aug 24 08:31:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alistair Popple X-Patchwork-Id: 11732373 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D0CFC913 for ; Mon, 24 Aug 2020 08:35:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9D59F206F0 for ; Mon, 24 Aug 2020 08:35:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=popple.id.au header.i=@popple.id.au header.b="HOjTtros" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D59F206F0 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=popple.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BB4266B0005; Mon, 24 Aug 2020 04:34:58 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 965956B0007; Mon, 24 Aug 2020 04:34:58 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7B6DE6B0008; Mon, 24 Aug 2020 04:34:58 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0100.hostedemail.com [216.40.44.100]) by kanga.kvack.org (Postfix) with ESMTP id 57B576B0007 for ; Mon, 24 Aug 2020 04:34:58 -0400 (EDT) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 18504180AD81A for ; Mon, 24 Aug 2020 08:34:58 +0000 (UTC) X-FDA: 77184801876.15.gate71_6205e5027051 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin15.hostedemail.com (Postfix) with ESMTP id D52D71814B0C1 for ; Mon, 24 Aug 2020 08:34:57 +0000 (UTC) X-Spam-Summary: 1,0,0,550f8412afa6548f,d41d8cd98f00b204,alistair@popple.id.au,,RULES_HIT:41:355:379:541:800:960:973:988:989:1260:1261:1311:1314:1345:1359:1431:1437:1515:1534:1542:1711:1730:1747:1777:1792:2393:2559:2562:2897:2914:3138:3139:3140:3141:3142:3353:3865:3867:3868:3870:3871:4321:5007:6117:6261:6653:7903:10004:11026:11473:11658:11914:12043:12296:12297:12438:12517:12519:12555:12679:12895:12986:13894:14093:14096:14181:14394:14721:21080:21451:21627:30003:30012:30025:30054:30056,0,RBL:203.11.71.1:@popple.id.au:.lbl8.mailshell.net-64.201.201.201 62.14.32.100;04yrp7kuchkqjdbfxc3jmpkfu3hhjypfr8pun1or4oef9awh61a37orehhujpup.oxa7rcmbobkhzfao3wsgzdnqwsx9mknqcdspfu6jiisqy1tqakmkfanxjemmzn1.o-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:110,LUA_SUMMARY:none X-HE-Tag: gate71_6205e5027051 X-Filterd-Recvd-Size: 4463 Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) by imf07.hostedemail.com (Postfix) with ESMTP for ; Mon, 24 Aug 2020 08:34:56 +0000 (UTC) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4BZlmZ05xxz9sTK; Mon, 24 Aug 2020 18:34:53 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=popple.id.au; s=202006; t=1598258094; bh=yRZeJ8KZbou6GV0bFnhnKPYHStI9GrYCBZFRBYS6p3M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HOjTtrosu7GyKTGzTOdwMv4eWaV9887xNiK29sJw3SipAzIxsF1s3iEQv7+lEhdAZ 96V0NiK8cuWicCuwjNfYEDGQBbfYYz2RZ4L5v/Dl21A7nUV6fmfY8HOdBsokKuwzhU jN9MRMYDK+KDiIpK5AuxdrzYYGpiYD2dyxlUgyiTZWjS0W9kZPKPtzLngVzIpp7ayj HNgmn+1pWGBN7pWEmi6du6CeLW1OZHwEDLyiHGrkNWrc5mN3D0zD8NqgnGXIBF7Ird m1lR7A5z8KD+Z3k3go/ItnpzlaDfnbTApho4fqfyZWGKdLUbs/T9y7hTMy79VgGCTK +URC2MAKSCy8Q== From: Alistair Popple To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Andrew Morton , Peter Xu , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , John Hubbard , Ralph Campbell , Alistair Popple , stable@vger.kernel.org Subject: [PATCH 2/2] mm/rmap: Fixup copying of soft dirty and uffd ptes Date: Mon, 24 Aug 2020 18:31:28 +1000 Message-Id: <20200824083128.12684-2-alistair@popple.id.au> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200824083128.12684-1-alistair@popple.id.au> References: <20200824083128.12684-1-alistair@popple.id.au> MIME-Version: 1.0 X-Rspamd-Queue-Id: D52D71814B0C1 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 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: During memory migration a pte is temporarily replaced with a migration swap pte. Some pte bits from the existing mapping such as the soft-dirty and uffd write-protect bits are preserved by copying these to the temporary migration swap pte. However these bits are not stored at the same location for swap and non-swap ptes. Therefore testing these bits requires using the appropriate helper function for the given pte type. Unfortunately several code locations were found where the wrong helper function is being used to test soft_dirty and uffd_wp bits which leads to them getting incorrectly set or cleared during page-migration. Fix these by using the correct tests based on pte type. Fixes: a5430dda8a3a ("mm/migrate: support un-addressable ZONE_DEVICE page in migration") Fixes: 8c3328f1f36a ("mm/migrate: migrate_vma() unmap page from vma while collecting pages") Fixes: f45ec5ff16a7 ("userfaultfd: wp: support swap and page migration") Signed-off-by: Alistair Popple Cc: stable@vger.kernel.org --- mm/migrate.c | 6 ++++-- mm/rmap.c | 9 +++++++-- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/mm/migrate.c b/mm/migrate.c index ddb64253fe3e..5bea19c496af 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2427,9 +2427,11 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp, entry = make_migration_entry(page, mpfn & MIGRATE_PFN_WRITE); swp_pte = swp_entry_to_pte(entry); - if (pte_soft_dirty(pte)) + if ((is_swap_pte(pte) && pte_swp_soft_dirty(pte)) + || (!is_swap_pte(pte) && pte_soft_dirty(pte))) swp_pte = pte_swp_mksoft_dirty(swp_pte); - if (pte_uffd_wp(pte)) + if ((is_swap_pte(pte) && pte_swp_uffd_wp(pte)) + || (!is_swap_pte(pte) && pte_uffd_wp(pte))) swp_pte = pte_swp_mkuffd_wp(swp_pte); set_pte_at(mm, addr, ptep, swp_pte); diff --git a/mm/rmap.c b/mm/rmap.c index 83cc459edc40..9425260774a1 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1511,9 +1511,14 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, */ entry = make_migration_entry(page, 0); swp_pte = swp_entry_to_pte(entry); - if (pte_soft_dirty(pteval)) + + /* + * pteval maps a zone device page and is therefore + * a swap pte. + */ + if (pte_swp_soft_dirty(pteval)) swp_pte = pte_swp_mksoft_dirty(swp_pte); - if (pte_uffd_wp(pteval)) + if (pte_swp_uffd_wp(pteval)) swp_pte = pte_swp_mkuffd_wp(swp_pte); set_pte_at(mm, pvmw.address, pvmw.pte, swp_pte); /*