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=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 D770EC2D0A3 for ; Tue, 3 Nov 2020 15:22:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6655220757 for ; Tue, 3 Nov 2020 15:22:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6655220757 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C814E6B006C; Tue, 3 Nov 2020 10:22:52 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BD90A6B007B; Tue, 3 Nov 2020 10:22:52 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9F4D96B0075; Tue, 3 Nov 2020 10:22:52 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0252.hostedemail.com [216.40.44.252]) by kanga.kvack.org (Postfix) with ESMTP id 5BB486B0075 for ; Tue, 3 Nov 2020 10:22:52 -0500 (EST) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 08BCA8249980 for ; Tue, 3 Nov 2020 15:22:52 +0000 (UTC) X-FDA: 77443474584.30.mouth43_140e31e272b9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin30.hostedemail.com (Postfix) with ESMTP id D02A3180B3AA7 for ; Tue, 3 Nov 2020 15:22:51 +0000 (UTC) X-HE-Tag: mouth43_140e31e272b9 X-Filterd-Recvd-Size: 4966 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf50.hostedemail.com (Postfix) with ESMTP for ; Tue, 3 Nov 2020 15:22:51 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 4E6A9AE53; Tue, 3 Nov 2020 15:22:50 +0000 (UTC) From: Vlastimil Babka To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Alexander Potapenko , Kees Cook , Michal Hocko , David Hildenbrand , Mateusz Nosek , Laura Abbott , Vlastimil Babka , "Rafael J. Wysocki" , Len Brown , Pavel Machek , linux-pm@vger.kernel.org Subject: [PATCH v2 3/5] kernel/power: allow hibernation with page_poison sanity checking Date: Tue, 3 Nov 2020 16:22:35 +0100 Message-Id: <20201103152237.9853-4-vbabka@suse.cz> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201103152237.9853-1-vbabka@suse.cz> References: <20201103152237.9853-1-vbabka@suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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: Page poisoning used to be incompatible with hibernation, as the state of poisoned pages was lost after resume, thus enabling CONFIG_HIBERNATION fo= rces CONFIG_PAGE_POISONING_NO_SANITY. For the same reason, the poisoning with = zeroes variant CONFIG_PAGE_POISONING_ZERO used to disable hibernation. The latte= r restriction was removed by commit 1ad1410f632d ("PM / Hibernate: allow hibernation with PAGE_POISONING_ZERO") and similarly for init_on_free by = commit 18451f9f9e58 ("PM: hibernate: fix crashes with init_on_free=3D1") by maki= ng sure free pages are cleared after resume. We can use the same mechanism to instead poison free pages with PAGE_POIS= ON after resume. This covers both zero and 0xAA patterns. Thus we can remove= the Kconfig restriction that disables page poison sanity checking when hibern= ation is enabled. Signed-off-by: Vlastimil Babka Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Pavel Machek Cc: --- kernel/power/hibernate.c | 2 +- kernel/power/power.h | 2 +- kernel/power/snapshot.c | 14 ++++++++++---- mm/Kconfig.debug | 1 - 4 files changed, 12 insertions(+), 7 deletions(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 2fc7d509a34f..da0b41914177 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -326,7 +326,7 @@ static int create_image(int platform_mode) =20 if (!in_suspend) { events_check_enabled =3D false; - clear_free_pages(); + clear_or_poison_free_pages(); } =20 platform_leave(platform_mode); diff --git a/kernel/power/power.h b/kernel/power/power.h index 24f12d534515..778bf431ec02 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -106,7 +106,7 @@ extern int create_basic_memory_bitmaps(void); extern void free_basic_memory_bitmaps(void); extern int hibernate_preallocate_memory(void); =20 -extern void clear_free_pages(void); +extern void clear_or_poison_free_pages(void); =20 /** * Auxiliary structure used for reading the snapshot image data and diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 46b1804c1ddf..6b1c84afa891 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1144,7 +1144,7 @@ void free_basic_memory_bitmaps(void) pr_debug("Basic memory bitmaps freed\n"); } =20 -void clear_free_pages(void) +void clear_or_poison_free_pages(void) { struct memory_bitmap *bm =3D free_pages_map; unsigned long pfn; @@ -1152,12 +1152,18 @@ void clear_free_pages(void) if (WARN_ON(!(free_pages_map))) return; =20 - if (IS_ENABLED(CONFIG_PAGE_POISONING_ZERO) || want_init_on_free()) { + if (page_poisoning_enabled() || want_init_on_free()) { memory_bm_position_reset(bm); pfn =3D memory_bm_next_pfn(bm); while (pfn !=3D BM_END_OF_MAP) { - if (pfn_valid(pfn)) - clear_highpage(pfn_to_page(pfn)); + if (pfn_valid(pfn)) { + struct page *page =3D pfn_to_page(pfn); + if (page_poisoning_enabled_static()) + kernel_poison_pages(page, 1); + else if (want_init_on_free()) + clear_highpage(page); + + } =20 pfn =3D memory_bm_next_pfn(bm); } diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug index 864f129f1937..c57786ad5be9 100644 --- a/mm/Kconfig.debug +++ b/mm/Kconfig.debug @@ -64,7 +64,6 @@ config PAGE_OWNER =20 config PAGE_POISONING bool "Poison pages after freeing" - select PAGE_POISONING_NO_SANITY if HIBERNATION help Fill the pages with poison patterns after free_pages() and verify the patterns before alloc_pages. The filling of the memory helps --=20 2.29.1