From patchwork Thu Oct 29 16:19:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 11866779 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 0115D6A2 for ; Thu, 29 Oct 2020 16:20:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A32F520790 for ; Thu, 29 Oct 2020 16:20:55 +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="iWwh/udv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A32F520790 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 D813C6B0070; Thu, 29 Oct 2020 12:20:54 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id D2EF36B0071; Thu, 29 Oct 2020 12:20:54 -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 BCFCC6B0073; Thu, 29 Oct 2020 12:20:54 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0208.hostedemail.com [216.40.44.208]) by kanga.kvack.org (Postfix) with ESMTP id 85EA26B0070 for ; Thu, 29 Oct 2020 12:20:54 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id EA2A3348D for ; Thu, 29 Oct 2020 16:20:53 +0000 (UTC) X-FDA: 77425476786.29.dirt21_62012e82728e Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id 64EBE180889AE for ; Thu, 29 Oct 2020 16:19:52 +0000 (UTC) X-Spam-Summary: 1,0,0,402def99a37bd872,d41d8cd98f00b204,rppt@kernel.org,,RULES_HIT:41:69:355:379:541:800:960:966:968:973:988:989:1260:1311:1314:1345:1359:1437:1515:1535:1544:1711:1730:1747:1777:1792:2194:2196:2198:2199:2200:2201:2393:2553:2559:2562:2693:2895:2897:3138:3139:3140:3141:3142:3355:3865:3866:3867:3868:3870:3871:3872:3874:4117:4250:4321:4385:4605:5007:6261:6653:6742:6743:7576:7903:8660:9592:10004:11026:11473:11658:11914:12043:12291:12296:12297:12438:12517:12519:12555:12679:12683:12895:12986:13148:13149:13161:13229:13230:13894:14096:14181:14394:14721:21063:21080:21325:21433:21627:21939:21966:21990:30054:30070:30090,0,RBL:198.145.29.99:@kernel.org:.lbl8.mailshell.net-64.100.201.201 62.2.0.100;04yfz1w7ohmayzy5tjcjjyo5ohmwnycoz4qzmn1r91z8i37o4rrq7rawe8q9d6j.fx4quw7nk1jgo9fnb9wiyifw5tu64w4xo13hhyxhsgrrfj1z6ncb4z1ofy56wej.r-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,L X-HE-Tag: dirt21_62012e82728e X-Filterd-Recvd-Size: 6953 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf04.hostedemail.com (Postfix) with ESMTP for ; Thu, 29 Oct 2020 16:19:51 +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 03BA620FC3; Thu, 29 Oct 2020 16:19:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603988390; bh=Iz7KyN+V6YK56PqFtmhKd3TakWN2xra2g1SEksnbwVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iWwh/udv6psprKZdwjB/YlWEY3V9aUIGxWhspe+BK019WtskP0vZrfStEaKajTzxe xknmcrFXFFqtCs2sQ8Agir2vwZTHfN02Rok80acaSKPxeVupMqhAIQyjYz8LhBnpdP qTdtY+jO3K1pgyk9l4BIkK96/jtl650ZRkYJtjkk= 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" , 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 , 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 Subject: [PATCH v2 2/4] PM: hibernate: make direct map manipulations more explicit Date: Thu, 29 Oct 2020 18:19:00 +0200 Message-Id: <20201029161902.19272-3-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201029161902.19272-1-rppt@kernel.org> References: <20201029161902.19272-1-rppt@kernel.org> MIME-Version: 1.0 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. On arm64 it is possible that a page would be removed from the direct map using set_direct_map_invalid_noflush() but __kernel_map_pages() will refuse to map this page back if DEBUG_PAGEALLOC is disabled. Introduce hibernate_map_page() that will explicitly use set_direct_map_{default,invalid}_noflush() for ARCH_HAS_SET_DIRECT_MAP case and debug_pagealloc_map_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 WARN_ON() so that future changes in set_memory APIs will not silently break hibernation. Signed-off-by: Mike Rapoport Acked-by: Rafael J. Wysocki --- include/linux/mm.h | 12 ------------ kernel/power/snapshot.c | 30 ++++++++++++++++++++++++++++-- 2 files changed, 28 insertions(+), 14 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 1fc0609056dc..14e397f3752c 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_DIRECT_MAP) extern void __kernel_map_pages(struct page *page, int numpages, int enable); -/* - * When called in DEBUG_PAGEALLOC context, the call should most likely be - * guarded by debug_pagealloc_enabled() or debug_pagealloc_enabled_static() - */ -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 numpages, int enable) { @@ -2948,8 +2938,6 @@ static inline void debug_pagealloc_map_pages(struct page *page, 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 numpages, int enable) {} #ifdef CONFIG_HIBERNATION diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 46b1804c1ddf..054c8cce4236 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -76,6 +76,32 @@ 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 */ +static inline void hibernate_map_page(struct page *page, int enable) +{ + if (IS_ENABLED(CONFIG_ARCH_HAS_SET_DIRECT_MAP)) { + unsigned long addr = (unsigned long)page_address(page); + int ret; + + /* + * This should not fail because remapping a page here means + * that we only update protection bits in an existing PTE. + * It is still worth to have WARN_ON() here if something + * changes and this will no longer be the case. + */ + if (enable) + ret = set_direct_map_default_noflush(page); + else + ret = set_direct_map_invalid_noflush(page); + + if (WARN_ON(ret)) + return; + + flush_tlb_kernel_range(addr, addr + PAGE_SIZE); + } else { + debug_pagealloc_map_pages(page, 1, enable); + } +} + 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 +1381,9 @@ 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, 1); do_copy_page(dst, page_address(s_page)); - kernel_map_pages(s_page, 1, 0); + hibernate_map_page(s_page, 0); } }