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 E35E5C388F7 for ; Fri, 13 Nov 2020 10:40:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7E2212224B for ; Fri, 13 Nov 2020 10:40:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7E2212224B 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 5A4A76B0099; Fri, 13 Nov 2020 05:40:51 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 25C736B0096; Fri, 13 Nov 2020 05:40:51 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CE28A6B009D; Fri, 13 Nov 2020 05:40:50 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0097.hostedemail.com [216.40.44.97]) by kanga.kvack.org (Postfix) with ESMTP id 904A86B0098 for ; Fri, 13 Nov 2020 05:40:50 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 20C9D1EF1 for ; Fri, 13 Nov 2020 10:40:50 +0000 (UTC) X-FDA: 77479051860.24.dust30_441437d2730e Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin24.hostedemail.com (Postfix) with ESMTP id 07FAD1A4A0 for ; Fri, 13 Nov 2020 10:40:50 +0000 (UTC) X-HE-Tag: dust30_441437d2730e X-Filterd-Recvd-Size: 5522 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf32.hostedemail.com (Postfix) with ESMTP for ; Fri, 13 Nov 2020 10:40:49 +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 3AECFAEFB; Fri, 13 Nov 2020 10:40:48 +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" Subject: [PATCH v3 3/5] kernel/power: allow hibernation with page_poison sanity checking Date: Fri, 13 Nov 2020 11:40:31 +0100 Message-Id: <20201113104033.22907-4-vbabka@suse.cz> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201113104033.22907-1-vbabka@suse.cz> References: <20201113104033.22907-1-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 Acked-by: Rafael J. Wysocki # for hibernatio= n --- include/linux/mm.h | 1 + kernel/power/hibernate.c | 2 +- kernel/power/power.h | 2 +- kernel/power/snapshot.c | 14 +++++++++++--- mm/Kconfig.debug | 1 - 5 files changed, 14 insertions(+), 6 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 5ab5358be2b3..b15000085ff2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2891,6 +2891,7 @@ static inline void kernel_unpoison_pages(struct pag= e *page, int numpages) #else static inline bool page_poisoning_enabled(void) { return false; } static inline bool page_poisoning_enabled_static(void) { return false; } +static inline void __kernel_poison_pages(struct page *page, int nunmpage= s) { } static inline void kernel_poison_pages(struct page *page, int numpages) = { } static inline void kernel_unpoison_pages(struct page *page, int numpages= ) { } #endif diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index d5d48404db37..559acef3fddb 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -329,7 +329,7 @@ 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 af534982062d..64b7aab9aee4 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1178,7 +1178,15 @@ void free_basic_memory_bitmaps(void) pr_debug("Basic memory bitmaps freed\n"); } =20 -void clear_free_pages(void) +static void clear_or_poison_free_page(struct page *page) +{ + if (page_poisoning_enabled_static()) + __kernel_poison_pages(page, 1); + else if (want_init_on_free()) + clear_highpage(page); +} + +void clear_or_poison_free_pages(void) { struct memory_bitmap *bm =3D free_pages_map; unsigned long pfn; @@ -1186,12 +1194,12 @@ 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)); + clear_or_poison_free_page(pfn_to_page(pfn)); =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 2.29.2