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=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 4705CC5517A for ; Mon, 9 Nov 2020 19:22:07 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DF94720789 for ; Mon, 9 Nov 2020 19:22:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="15E9e9iG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF94720789 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 636416B005D; Mon, 9 Nov 2020 14:22:06 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 5E3C56B006C; Mon, 9 Nov 2020 14:22:06 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4849E6B006E; Mon, 9 Nov 2020 14:22:06 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0183.hostedemail.com [216.40.44.183]) by kanga.kvack.org (Postfix) with ESMTP id 1D9EF6B005D for ; Mon, 9 Nov 2020 14:22:06 -0500 (EST) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id BC4971EF1 for ; Mon, 9 Nov 2020 19:22:05 +0000 (UTC) X-FDA: 77465850210.18.game06_541688e272ee Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin18.hostedemail.com (Postfix) with ESMTP id 8FFF4100ED3B4 for ; Mon, 9 Nov 2020 19:22:05 +0000 (UTC) X-HE-Tag: game06_541688e272ee X-Filterd-Recvd-Size: 7472 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf13.hostedemail.com (Postfix) with ESMTP for ; Mon, 9 Nov 2020 19:22:04 +0000 (UTC) Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CD3392074F; Mon, 9 Nov 2020 19:21:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604949724; bh=0+/Ijks+tfwTVzbr4Km98lXXrR2UvY+Np3e94RlQ6xg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=15E9e9iGIiP0778ceoXxhDg2WTSbP9tN/0WArX4Y6hxOlkrbAxSldulnMfvaeKSkT Ok6UuM0nTHwTXj5dmbTVRnpxL/uSftxXKSK/U0AUHE/S9WRN/CKoXuhBWNMF70lC7L a2mv+QhB91uyWUJVF9wrKutUyiix6jqpwnIgB9LI= From: Mike Rapoport To: Andrew Morton Cc: Albert Ou , Andy Lutomirski , Benjamin Herrenschmidt , Borislav Petkov , Catalin Marinas , Christian Borntraeger , Christoph Lameter , "David S. Miller" , Dave Hansen , David Hildenbrand , David Rientjes , "Edgecombe, Rick P" , "H. Peter Anvin" , Heiko Carstens , Ingo Molnar , Joonsoo Kim , "Kirill A . Shutemov" , "Kirill A. Shutemov" , Len Brown , Michael Ellerman , Mike Rapoport , Mike Rapoport , Palmer Dabbelt , Paul Mackerras , Paul Walmsley , Pavel Machek , Pekka Enberg , Peter Zijlstra , "Rafael J. Wysocki" , Thomas Gleixner , Vasily Gorbik , Vlastimil Babka , Will Deacon , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-pm@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org, "Rafael J . Wysocki" Subject: [PATCH v7 2/4] PM: hibernate: make direct map manipulations more explicit Date: Mon, 9 Nov 2020 21:21:26 +0200 Message-Id: <20201109192128.960-3-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201109192128.960-1-rppt@kernel.org> References: <20201109192128.960-1-rppt@kernel.org> 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: From: Mike Rapoport When DEBUG_PAGEALLOC or ARCH_HAS_SET_DIRECT_MAP is enabled a page may be not present in the direct map and has to be explicitly mapped before it could be copied. Introduce hibernate_map_page() and hibernation_unmap_page() that will explicitly use set_direct_map_{default,invalid}_noflush() for ARCH_HAS_SET_DIRECT_MAP case and debug_pagealloc_{map,unmap}_pages() for DEBUG_PAGEALLOC case. The remapping of the pages in safe_copy_page() presumes that it only changes protection bits in an existing PTE and so it is safe to ignore return value of set_direct_map_{default,invalid}_noflush(). Still, add a pr_warn() so that future changes in set_memory APIs will not silently break hibernation. Signed-off-by: Mike Rapoport Acked-by: Rafael J. Wysocki Reviewed-by: David Hildenbrand Acked-by: Kirill A. Shutemov Acked-by: Vlastimil Babka --- include/linux/mm.h | 12 ------------ kernel/power/snapshot.c | 38 ++++++++++++++++++++++++++++++++++++-- 2 files changed, 36 insertions(+), 14 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index bb8c70178f4e..e198b938f5c5 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2927,16 +2927,6 @@ static inline bool debug_pagealloc_enabled_static(= void) #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_ARCH_HAS_SET_DIREC= T_MAP) extern void __kernel_map_pages(struct page *page, int numpages, int enab= le); =20 -/* - * When called in DEBUG_PAGEALLOC context, the call should most likely b= e - * guarded by debug_pagealloc_enabled() or debug_pagealloc_enabled_stati= c() - */ -static inline void -kernel_map_pages(struct page *page, int numpages, int enable) -{ - __kernel_map_pages(page, numpages, enable); -} - static inline void debug_pagealloc_map_pages(struct page *page, int nump= ages) { if (debug_pagealloc_enabled_static()) @@ -2953,8 +2943,6 @@ static inline void debug_pagealloc_unmap_pages(stru= ct page *page, int numpages) extern bool kernel_page_present(struct page *page); #endif /* CONFIG_HIBERNATION */ #else /* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_DIRECT_MAP */ -static inline void -kernel_map_pages(struct page *page, int numpages, int enable) {} static inline void debug_pagealloc_map_pages(struct page *page, int nump= ages) {} static inline void debug_pagealloc_unmap_pages(struct page *page, int nu= mpages) {} #ifdef CONFIG_HIBERNATION diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 46b1804c1ddf..d848377dd8dc 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -76,6 +76,40 @@ static inline void hibernate_restore_protect_page(void= *page_address) {} static inline void hibernate_restore_unprotect_page(void *page_address) = {} #endif /* CONFIG_STRICT_KERNEL_RWX && CONFIG_ARCH_HAS_SET_MEMORY */ =20 + +/* + * The calls to set_direct_map_*() should not fail because remapping a p= age + * here means that we only update protection bits in an existing PTE. + * It is still worth to have a warning here if something changes and thi= s + * will no longer be the case. + */ +static inline void hibernate_map_page(struct page *page) +{ + if (IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP)) { + int ret =3D set_direct_map_default_noflush(page); + + if (ret) + pr_warn_once("Failed to remap page\n"); + } else { + debug_pagealloc_map_pages(page, 1); + } +} + +static inline void hibernate_unmap_page(struct page *page) +{ + if (IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP)) { + unsigned long addr =3D (unsigned long)page_address(page); + int ret =3D set_direct_map_invalid_noflush(page); + + if (ret) + pr_warn_once("Failed to remap page\n"); + + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + } else { + debug_pagealloc_unmap_pages(page, 1); + } +} + static int swsusp_page_is_free(struct page *); static void swsusp_set_page_forbidden(struct page *); static void swsusp_unset_page_forbidden(struct page *); @@ -1355,9 +1389,9 @@ static void safe_copy_page(void *dst, struct page *= s_page) if (kernel_page_present(s_page)) { do_copy_page(dst, page_address(s_page)); } else { - kernel_map_pages(s_page, 1, 1); + hibernate_map_page(s_page); do_copy_page(dst, page_address(s_page)); - kernel_map_pages(s_page, 1, 0); + hibernate_unmap_page(s_page); } } =20 --=20 2.28.0