From patchwork Sun Nov 8 06:57:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 321734 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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 12198C388F9 for ; Sun, 8 Nov 2020 06:58:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C441420897 for ; Sun, 8 Nov 2020 06:58:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604818705; bh=590zK77IIK/GRU0iesSEW1g1nAaxcF2LlciXyBdNWeI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2qq7cOyAOCoZkcQqvXRnyagQ9hoPfpkPD0v5WlKv41/tNlO4fDhGzlfSDtzmbcnIy LGc7QT1rpc3oh+2+r7gjNaM4FgIfoyU48dkTMPNUIfet9W/l+2Ftqtg+R0TkFA56YS TagAr/Qq81vInHeSZCb0B+gfzlKFlxgqGVi3z22U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727457AbgKHG6Z (ORCPT ); Sun, 8 Nov 2020 01:58:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:36370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727452AbgKHG6Y (ORCPT ); Sun, 8 Nov 2020 01:58:24 -0500 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 48F71221FE; Sun, 8 Nov 2020 06:58:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604818703; bh=590zK77IIK/GRU0iesSEW1g1nAaxcF2LlciXyBdNWeI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S1Y5DBswnJRHvAhvlNmC6rXkkgTQxCugaaOkUKj5K5HgitkS61OQ0AYHixTLTqX7c AsmYAXrwvk4Jm9jm5qdYR9OjHM/USSXU7ddTb6jnhZOcumAy1eP1nZ3lLOSywTmN7K RZjefYfRwtk+pch6QAA8dQU6ZB0oI3gOHb8aaSxU= 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 Subject: [PATCH v5 1/5] mm: introduce debug_pagealloc_{map, unmap}_pages() helpers Date: Sun, 8 Nov 2020 08:57:54 +0200 Message-Id: <20201108065758.1815-2-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201108065758.1815-1-rppt@kernel.org> References: <20201108065758.1815-1-rppt@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Mike Rapoport When CONFIG_DEBUG_PAGEALLOC is enabled, it unmaps pages from the kernel direct mapping after free_pages(). The pages than need to be mapped back before they could be used. Theese mapping operations use __kernel_map_pages() guarded with with debug_pagealloc_enabled(). The only place that calls __kernel_map_pages() without checking whether DEBUG_PAGEALLOC is enabled is the hibernation code that presumes availability of this function when ARCH_HAS_SET_DIRECT_MAP is set. Still, on arm64, __kernel_map_pages() will bail out when DEBUG_PAGEALLOC is not enabled but set_direct_map_invalid_noflush() may render some pages not present in the direct map and hibernation code won't be able to save such pages. To make page allocation debugging and hibernation interaction more robust, the dependency on DEBUG_PAGEALLOC or ARCH_HAS_SET_DIRECT_MAP has to be made more explicit. Start with combining the guard condition and the call to __kernel_map_pages() into debug_pagealloc_map_pages() and debug_pagealloc_unmap_pages() functions to emphasize that __kernel_map_pages() should not be called without DEBUG_PAGEALLOC and use these new functions to map/unmap pages when page allocation debugging is enabled. Signed-off-by: Mike Rapoport Reviewed-by: David Hildenbrand Acked-by: Kirill A. Shutemov Acked-by: Vlastimil Babka --- include/linux/mm.h | 15 +++++++++++++++ mm/memory_hotplug.c | 3 +-- mm/page_alloc.c | 6 ++---- mm/slab.c | 16 +++++++--------- 4 files changed, 25 insertions(+), 15 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index ef360fe70aaf..bb8c70178f4e 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2936,12 +2936,27 @@ 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) +{ + if (debug_pagealloc_enabled_static()) + __kernel_map_pages(page, numpages, 1); +} + +static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) +{ + if (debug_pagealloc_enabled_static()) + __kernel_map_pages(page, numpages, 0); +} + #ifdef CONFIG_HIBERNATION 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) {} +static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {} #ifdef CONFIG_HIBERNATION static inline bool kernel_page_present(struct page *page) { return true; } #endif /* CONFIG_HIBERNATION */ diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index b44d4c7ba73b..f18f86ba2a68 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -614,8 +614,7 @@ void generic_online_page(struct page *page, unsigned int order) * so we should map it first. This is better than introducing a special * case in page freeing fast path. */ - if (debug_pagealloc_enabled_static()) - kernel_map_pages(page, 1 << order, 1); + debug_pagealloc_map_pages(page, 1 << order); __free_pages_core(page, order); totalram_pages_add(1UL << order); #ifdef CONFIG_HIGHMEM diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 23f5066bd4a5..db1bf70458d0 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1272,8 +1272,7 @@ static __always_inline bool free_pages_prepare(struct page *page, */ arch_free_page(page, order); - if (debug_pagealloc_enabled_static()) - kernel_map_pages(page, 1 << order, 0); + debug_pagealloc_unmap_pages(page, 1 << order); kasan_free_nondeferred_pages(page, order); @@ -2270,8 +2269,7 @@ inline void post_alloc_hook(struct page *page, unsigned int order, set_page_refcounted(page); arch_alloc_page(page, order); - if (debug_pagealloc_enabled_static()) - kernel_map_pages(page, 1 << order, 1); + debug_pagealloc_map_pages(page, 1 << order); kasan_alloc_pages(page, order); kernel_poison_pages(page, 1 << order, 1); set_page_owner(page, order, gfp_flags); diff --git a/mm/slab.c b/mm/slab.c index b1113561b98b..07317386e150 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -1428,21 +1428,19 @@ static bool is_debug_pagealloc_cache(struct kmem_cache *cachep) return false; } -#ifdef CONFIG_DEBUG_PAGEALLOC static void slab_kernel_map(struct kmem_cache *cachep, void *objp, int map) { if (!is_debug_pagealloc_cache(cachep)) return; - kernel_map_pages(virt_to_page(objp), cachep->size / PAGE_SIZE, map); + if (map) + debug_pagealloc_map_pages(virt_to_page(objp), + cachep->size / PAGE_SIZE); + else + debug_pagealloc_unmap_pages(virt_to_page(objp), + cachep->size / PAGE_SIZE); } -#else -static inline void slab_kernel_map(struct kmem_cache *cachep, void *objp, - int map) {} - -#endif - static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) { int size = cachep->object_size; @@ -2062,7 +2060,7 @@ int __kmem_cache_create(struct kmem_cache *cachep, slab_flags_t flags) #if DEBUG /* - * If we're going to use the generic kernel_map_pages() + * If we're going to use the generic debug_pagealloc_map_pages() * poisoning, then it's going to smash the contents of * the redzone and userword anyhow, so switch them off. */ From patchwork Sun Nov 8 06:57:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 321733 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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 D207EC388F2 for ; Sun, 8 Nov 2020 06:58:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D07520897 for ; Sun, 8 Nov 2020 06:58:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604818727; bh=0+/Ijks+tfwTVzbr4Km98lXXrR2UvY+Np3e94RlQ6xg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ieF1GTJDwXXf7/tjCuUuNGZWeUW5R6AuOoy6LtWbcmb9sLtWB0s36m8O0MlXbFXrR bjSNDx5/cDryZA4bSCIH1ONLUbW5muiVJw9Dhx22kdm8iBukmVIslpnhCBoEp4HXFD JyrxzfheOgS/5LxRhh3IA5tp9xfVKXJpW6I3hYMQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726014AbgKHG6q (ORCPT ); Sun, 8 Nov 2020 01:58:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:36758 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726062AbgKHG6q (ORCPT ); Sun, 8 Nov 2020 01:58:46 -0500 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 2003622210; Sun, 8 Nov 2020 06:58:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604818725; bh=0+/Ijks+tfwTVzbr4Km98lXXrR2UvY+Np3e94RlQ6xg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kojy+ghyD1q7+EkttkLyjKdeW/x7n35VGmuZbOsZ8H9qHCfBB04pMlemdjxjAiZxj b4raIaTvdFV1sVmrUS8fiCsOP50b3YEG4eZXd8KF2TDGzzESACuFOBYXb2F6YA69YC OjclfcDeaofFbFA/P9NqmCTxxkKxrFvP9msEiuC8= 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 v5 3/5] PM: hibernate: make direct map manipulations more explicit Date: Sun, 8 Nov 2020 08:57:56 +0200 Message-Id: <20201108065758.1815-4-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201108065758.1815-1-rppt@kernel.org> References: <20201108065758.1815-1-rppt@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org 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_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) { if (debug_pagealloc_enabled_static()) @@ -2953,8 +2943,6 @@ static inline void debug_pagealloc_unmap_pages(struct 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 numpages) {} static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {} #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 */ + +/* + * The calls to set_direct_map_*() 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 a warning here if something changes and this + * 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 = 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 = (unsigned long)page_address(page); + int ret = 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); } } From patchwork Sun Nov 8 06:57:58 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 321732 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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 20697C388F2 for ; Sun, 8 Nov 2020 06:59:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DC94D20719 for ; Sun, 8 Nov 2020 06:59:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604818748; bh=zY00vAD1luWw8Wz9ntfdosu1D6lwJ6iTAdVQg6SgGXI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BocrkO2VOLHX7ZKQflc9yvPeLCubZ6lyXHtHoeF+oB8wLIKtbRv2r5zuYSuuUZigr 2IvFDOuumXLF8fJBmajSBRNuc5jUi3Jv1huFVhtxVsUNt2bklxhfKA5C7nmXQrkYQ5 LpMr4VnMCmarqOmCNjFbgJ6anN9syQsC+rhXokns= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726206AbgKHG7I (ORCPT ); Sun, 8 Nov 2020 01:59:08 -0500 Received: from mail.kernel.org ([198.145.29.99]:37184 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726062AbgKHG7I (ORCPT ); Sun, 8 Nov 2020 01:59:08 -0500 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 C2107221FE; Sun, 8 Nov 2020 06:58:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604818747; bh=zY00vAD1luWw8Wz9ntfdosu1D6lwJ6iTAdVQg6SgGXI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uZQotty/fCgSAotIoYPPjcleeGFQedZ2bXn1MRORp/bIAqmn6GCWAIBmKHllxFrNq tYDNPq2tKZV1KfkQLXAqFbMI7lSkhDmdOOnBLTD8vmdi4Kxgu9YUr/5kgD2A6CtDp6 oVY7PS5zQhpEg7nfD0kucNDwH5IiyQ87oPOjfrKg= 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 Subject: [PATCH v5 5/5] arch, mm: make kernel_page_present() always available Date: Sun, 8 Nov 2020 08:57:58 +0200 Message-Id: <20201108065758.1815-6-rppt@kernel.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201108065758.1815-1-rppt@kernel.org> References: <20201108065758.1815-1-rppt@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Mike Rapoport For architectures that enable ARCH_HAS_SET_MEMORY having the ability to verify that a page is mapped in the kernel direct map can be useful regardless of hibernation. Add RISC-V implementation of kernel_page_present(), update its forward declarations and stubs to be a part of set_memory API and remove ugly ifdefery in inlcude/linux/mm.h around current declarations of kernel_page_present(). Signed-off-by: Mike Rapoport Acked-by: Kirill A. Shutemov --- arch/arm64/include/asm/cacheflush.h | 1 + arch/arm64/mm/pageattr.c | 4 +--- arch/riscv/include/asm/set_memory.h | 1 + arch/riscv/mm/pageattr.c | 29 +++++++++++++++++++++++++++++ arch/x86/include/asm/set_memory.h | 1 + arch/x86/mm/pat/set_memory.c | 4 +--- include/linux/mm.h | 7 ------- include/linux/set_memory.h | 5 +++++ 8 files changed, 39 insertions(+), 13 deletions(-) diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h index 9384fd8fc13c..45217f21f1fe 100644 --- a/arch/arm64/include/asm/cacheflush.h +++ b/arch/arm64/include/asm/cacheflush.h @@ -140,6 +140,7 @@ int set_memory_valid(unsigned long addr, int numpages, int enable); int set_direct_map_invalid_noflush(struct page *page); int set_direct_map_default_noflush(struct page *page); +bool kernel_page_present(struct page *page); #include diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 439325532be1..92eccaf595c8 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -186,8 +186,8 @@ void __kernel_map_pages(struct page *page, int numpages, int enable) set_memory_valid((unsigned long)page_address(page), numpages, enable); } +#endif /* CONFIG_DEBUG_PAGEALLOC */ -#ifdef CONFIG_HIBERNATION /* * This function is used to determine if a linear map page has been marked as * not-valid. Walk the page table and check the PTE_VALID bit. This is based @@ -234,5 +234,3 @@ bool kernel_page_present(struct page *page) ptep = pte_offset_kernel(pmdp, addr); return pte_valid(READ_ONCE(*ptep)); } -#endif /* CONFIG_HIBERNATION */ -#endif /* CONFIG_DEBUG_PAGEALLOC */ diff --git a/arch/riscv/include/asm/set_memory.h b/arch/riscv/include/asm/set_memory.h index 4c5bae7ca01c..d690b08dff2a 100644 --- a/arch/riscv/include/asm/set_memory.h +++ b/arch/riscv/include/asm/set_memory.h @@ -24,6 +24,7 @@ static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; } int set_direct_map_invalid_noflush(struct page *page); int set_direct_map_default_noflush(struct page *page); +bool kernel_page_present(struct page *page); #endif /* __ASSEMBLY__ */ diff --git a/arch/riscv/mm/pageattr.c b/arch/riscv/mm/pageattr.c index 321b09d2e2ea..87ba5a68bbb8 100644 --- a/arch/riscv/mm/pageattr.c +++ b/arch/riscv/mm/pageattr.c @@ -198,3 +198,32 @@ void __kernel_map_pages(struct page *page, int numpages, int enable) __pgprot(0), __pgprot(_PAGE_PRESENT)); } #endif + +bool kernel_page_present(struct page *page) +{ + unsigned long addr = (unsigned long)page_address(page); + pgd_t *pgd; + pud_t *pud; + p4d_t *p4d; + pmd_t *pmd; + pte_t *pte; + + pgd = pgd_offset_k(addr); + if (!pgd_present(*pgd)) + return false; + + p4d = p4d_offset(pgd, addr); + if (!p4d_present(*p4d)) + return false; + + pud = pud_offset(p4d, addr); + if (!pud_present(*pud)) + return false; + + pmd = pmd_offset(pud, addr); + if (!pmd_present(*pmd)) + return false; + + pte = pte_offset_kernel(pmd, addr); + return pte_present(*pte); +} diff --git a/arch/x86/include/asm/set_memory.h b/arch/x86/include/asm/set_memory.h index 5948218f35c5..4352f08bfbb5 100644 --- a/arch/x86/include/asm/set_memory.h +++ b/arch/x86/include/asm/set_memory.h @@ -82,6 +82,7 @@ int set_pages_rw(struct page *page, int numpages); int set_direct_map_invalid_noflush(struct page *page); int set_direct_map_default_noflush(struct page *page); +bool kernel_page_present(struct page *page); extern int kernel_set_to_readonly; diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index bc9be96b777f..16f878c26667 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -2226,8 +2226,8 @@ void __kernel_map_pages(struct page *page, int numpages, int enable) arch_flush_lazy_mmu_mode(); } +#endif /* CONFIG_DEBUG_PAGEALLOC */ -#ifdef CONFIG_HIBERNATION bool kernel_page_present(struct page *page) { unsigned int level; @@ -2239,8 +2239,6 @@ bool kernel_page_present(struct page *page) pte = lookup_address((unsigned long)page_address(page), &level); return (pte_val(*pte) & _PAGE_PRESENT); } -#endif /* CONFIG_HIBERNATION */ -#endif /* CONFIG_DEBUG_PAGEALLOC */ int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address, unsigned numpages, unsigned long page_flags) diff --git a/include/linux/mm.h b/include/linux/mm.h index 260113ba660a..fe9a8d35a6eb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2942,16 +2942,9 @@ static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) if (debug_pagealloc_enabled_static()) __kernel_map_pages(page, numpages, 0); } - -#ifdef CONFIG_HIBERNATION -extern bool kernel_page_present(struct page *page); -#endif /* CONFIG_HIBERNATION */ #else /* CONFIG_DEBUG_PAGEALLOC */ static inline void debug_pagealloc_map_pages(struct page *page, int numpages) {} static inline void debug_pagealloc_unmap_pages(struct page *page, int numpages) {} -#ifdef CONFIG_HIBERNATION -static inline bool kernel_page_present(struct page *page) { return true; } -#endif /* CONFIG_HIBERNATION */ #endif /* CONFIG_DEBUG_PAGEALLOC */ #ifdef __HAVE_ARCH_GATE_AREA diff --git a/include/linux/set_memory.h b/include/linux/set_memory.h index 860e0f843c12..fe1aa4e54680 100644 --- a/include/linux/set_memory.h +++ b/include/linux/set_memory.h @@ -23,6 +23,11 @@ static inline int set_direct_map_default_noflush(struct page *page) { return 0; } + +static inline bool kernel_page_present(struct page *page) +{ + return true; +} #endif #ifndef set_mce_nospec