From patchwork Mon Sep 30 12:29:14 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 11166585 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 621CF112B for ; Mon, 30 Sep 2019 12:29:41 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 21BCE2190F for ; Mon, 30 Sep 2019 12:29:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21BCE2190F 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 884B26B0007; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 757276B000C; Mon, 30 Sep 2019 08:29:32 -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 55C726B0007; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0065.hostedemail.com [216.40.44.65]) by kanga.kvack.org (Postfix) with ESMTP id 27E2F6B0008 for ; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with SMTP id CB7B782437C9 for ; Mon, 30 Sep 2019 12:29:31 +0000 (UTC) X-FDA: 75991517742.14.ghost01_532144c761359 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,vbabka@suse.cz,:akpm@linux-foundation.org::linux-kernel@vger.kernel.org:kasan-dev@googlegroups.com:cai@lca.pw:kirill.shutemov@linux.intel.com:willy@infradead.org:mgorman@techsingularity.net:mhocko@kernel.org:vbabka@suse.cz:kirill@shutemov.name,RULES_HIT:30012:30054:30070:30075,0,RBL:195.135.220.15:@suse.cz:.lbl8.mailshell.net-62.2.6.2 64.100.201.201,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,LFtime:26,LUA_SUMMARY:none X-HE-Tag: ghost01_532144c761359 X-Filterd-Recvd-Size: 6991 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf18.hostedemail.com (Postfix) with ESMTP for ; Mon, 30 Sep 2019 12:29:31 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D4FB9AE0C; Mon, 30 Sep 2019 12:29:28 +0000 (UTC) From: Vlastimil Babka To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Qian Cai , "Kirill A. Shutemov" , Matthew Wilcox , Mel Gorman , Michal Hocko , Vlastimil Babka , "Kirill A . Shutemov" Subject: [PATCH v2 1/3] mm, page_owner: fix off-by-one error in __set_page_owner_handle() Date: Mon, 30 Sep 2019 14:29:14 +0200 Message-Id: <20190930122916.14969-2-vbabka@suse.cz> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190930122916.14969-1-vbabka@suse.cz> References: <20190930122916.14969-1-vbabka@suse.cz> 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: As noted by Kirill, commit 7e2f2a0cd17c ("mm, page_owner: record page owner for each subpage") has introduced an off-by-one error in __set_page_owner_handle() when looking up page_ext for subpages. As a result, the head page page_owner info is set twice, while for the last tail page, it's not set at all. Fix this and also make the code more efficient by advancing the page_ext pointer we already have, instead of calling lookup_page_ext() for each subpage. Since the full size of struct page_ext is not known at compile time, we can't use a simple page_ext++ statement, so introduce a page_ext_next() inline function for that. Reported-by: Kirill A. Shutemov Fixes: 7e2f2a0cd17c ("mm, page_owner: record page owner for each subpage") Signed-off-by: Vlastimil Babka Acked-by: Kirill A. Shutemov --- include/linux/page_ext.h | 8 ++++++++ mm/page_ext.c | 23 +++++++++-------------- mm/page_owner.c | 15 +++++++-------- 3 files changed, 24 insertions(+), 22 deletions(-) diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h index 682fd465df06..5e856512bafb 100644 --- a/include/linux/page_ext.h +++ b/include/linux/page_ext.h @@ -36,6 +36,7 @@ struct page_ext { unsigned long flags; }; +extern unsigned long page_ext_size; extern void pgdat_page_ext_init(struct pglist_data *pgdat); #ifdef CONFIG_SPARSEMEM @@ -52,6 +53,13 @@ static inline void page_ext_init(void) struct page_ext *lookup_page_ext(const struct page *page); +static inline struct page_ext *page_ext_next(struct page_ext *curr) +{ + void *next = curr; + next += page_ext_size; + return next; +} + #else /* !CONFIG_PAGE_EXTENSION */ struct page_ext; diff --git a/mm/page_ext.c b/mm/page_ext.c index 5f5769c7db3b..4ade843ff588 100644 --- a/mm/page_ext.c +++ b/mm/page_ext.c @@ -67,8 +67,9 @@ static struct page_ext_operations *page_ext_ops[] = { #endif }; +unsigned long page_ext_size = sizeof(struct page_ext); + static unsigned long total_usage; -static unsigned long extra_mem; static bool __init invoke_need_callbacks(void) { @@ -78,9 +79,8 @@ static bool __init invoke_need_callbacks(void) for (i = 0; i < entries; i++) { if (page_ext_ops[i]->need && page_ext_ops[i]->need()) { - page_ext_ops[i]->offset = sizeof(struct page_ext) + - extra_mem; - extra_mem += page_ext_ops[i]->size; + page_ext_ops[i]->offset = page_ext_size; + page_ext_size += page_ext_ops[i]->size; need = true; } } @@ -99,14 +99,9 @@ static void __init invoke_init_callbacks(void) } } -static unsigned long get_entry_size(void) -{ - return sizeof(struct page_ext) + extra_mem; -} - static inline struct page_ext *get_entry(void *base, unsigned long index) { - return base + get_entry_size() * index; + return base + page_ext_size * index; } #if !defined(CONFIG_SPARSEMEM) @@ -156,7 +151,7 @@ static int __init alloc_node_page_ext(int nid) !IS_ALIGNED(node_end_pfn(nid), MAX_ORDER_NR_PAGES)) nr_pages += MAX_ORDER_NR_PAGES; - table_size = get_entry_size() * nr_pages; + table_size = page_ext_size * nr_pages; base = memblock_alloc_try_nid( table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS), @@ -234,7 +229,7 @@ static int __meminit init_section_page_ext(unsigned long pfn, int nid) if (section->page_ext) return 0; - table_size = get_entry_size() * PAGES_PER_SECTION; + table_size = page_ext_size * PAGES_PER_SECTION; base = alloc_page_ext(table_size, nid); /* @@ -254,7 +249,7 @@ static int __meminit init_section_page_ext(unsigned long pfn, int nid) * we need to apply a mask. */ pfn &= PAGE_SECTION_MASK; - section->page_ext = (void *)base - get_entry_size() * pfn; + section->page_ext = (void *)base - page_ext_size * pfn; total_usage += table_size; return 0; } @@ -267,7 +262,7 @@ static void free_page_ext(void *addr) struct page *page = virt_to_page(addr); size_t table_size; - table_size = get_entry_size() * PAGES_PER_SECTION; + table_size = page_ext_size * PAGES_PER_SECTION; BUG_ON(PageReserved(page)); kmemleak_free(addr); diff --git a/mm/page_owner.c b/mm/page_owner.c index dee931184788..d3cf5d336ccf 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -156,10 +156,10 @@ void __reset_page_owner(struct page *page, unsigned int order) handle = save_stack(GFP_NOWAIT | __GFP_NOWARN); #endif + page_ext = lookup_page_ext(page); + if (unlikely(!page_ext)) + return; for (i = 0; i < (1 << order); i++) { - page_ext = lookup_page_ext(page + i); - if (unlikely(!page_ext)) - continue; __clear_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags); #ifdef CONFIG_DEBUG_PAGEALLOC if (debug_pagealloc_enabled()) { @@ -167,6 +167,7 @@ void __reset_page_owner(struct page *page, unsigned int order) page_owner->free_handle = handle; } #endif + page_ext = page_ext_next(page_ext); } } @@ -186,7 +187,7 @@ static inline void __set_page_owner_handle(struct page *page, __set_bit(PAGE_EXT_OWNER, &page_ext->flags); __set_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags); - page_ext = lookup_page_ext(page + i); + page_ext = page_ext_next(page_ext); } } @@ -224,12 +225,10 @@ void __split_page_owner(struct page *page, unsigned int order) if (unlikely(!page_ext)) return; - page_owner = get_page_owner(page_ext); - page_owner->order = 0; - for (i = 1; i < (1 << order); i++) { - page_ext = lookup_page_ext(page + i); + for (i = 0; i < (1 << order); i++) { page_owner = get_page_owner(page_ext); page_owner->order = 0; + page_ext = page_ext_next(page_ext); } } From patchwork Mon Sep 30 12:29:15 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 11166583 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 D73FF112B for ; Mon, 30 Sep 2019 12:29:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 936FA2086A for ; Mon, 30 Sep 2019 12:29:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 936FA2086A 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 6211A6B0005; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 5F7256B0008; Mon, 30 Sep 2019 08:29:32 -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 4E6816B000A; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0151.hostedemail.com [216.40.44.151]) by kanga.kvack.org (Postfix) with ESMTP id 0D44A6B0005 for ; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id A6DFF180AD804 for ; Mon, 30 Sep 2019 12:29:31 +0000 (UTC) X-FDA: 75991517742.25.hot13_531d961e91129 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,vbabka@suse.cz,:akpm@linux-foundation.org::linux-kernel@vger.kernel.org:kasan-dev@googlegroups.com:cai@lca.pw:kirill.shutemov@linux.intel.com:willy@infradead.org:mgorman@techsingularity.net:mhocko@kernel.org:vbabka@suse.cz:dvyukov@google.com:walter-zh.wu@mediatek.com:aryabinin@virtuozzo.com,RULES_HIT:30045:30054,0,RBL:195.135.220.15:@suse.cz:.lbl8.mailshell.net-62.2.6.2 64.100.201.201,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,LFtime:27,LUA_SUMMARY:none X-HE-Tag: hot13_531d961e91129 X-Filterd-Recvd-Size: 10428 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf24.hostedemail.com (Postfix) with ESMTP for ; Mon, 30 Sep 2019 12:29:31 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id E8F02AFE8; Mon, 30 Sep 2019 12:29:28 +0000 (UTC) From: Vlastimil Babka To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Qian Cai , "Kirill A. Shutemov" , Matthew Wilcox , Mel Gorman , Michal Hocko , Vlastimil Babka , Dmitry Vyukov , Walter Wu , Andrey Ryabinin Subject: [PATCH v2 2/3] mm, page_owner: decouple freeing stack trace from debug_pagealloc Date: Mon, 30 Sep 2019 14:29:15 +0200 Message-Id: <20190930122916.14969-3-vbabka@suse.cz> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190930122916.14969-1-vbabka@suse.cz> References: <20190930122916.14969-1-vbabka@suse.cz> 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: The commit 8974558f49a6 ("mm, page_owner, debug_pagealloc: save and dump freeing stack trace") enhanced page_owner to also store freeing stack trace, when debug_pagealloc is also enabled. KASAN would also like to do this [1] to improve error reports to debug e.g. UAF issues. Kirill has suggested that the freeing stack trace saving should be also possible to be enabled separately. This patch therefore introduces a new kernel parameter page_owner_free to enable the functionality in addition to the existing page_owner parameter. The free stack saving is thus enabled in these cases: 1) booting with page_owner=on and debug_pagealloc=on 2) booting a KASAN kernel with page_owner=on 3) booting with page_owner=on and page_owner_free=on To minimize runtime CPU and memory overhead when not boot-time enabled, the patch introduces a new static key and struct page_ext_operations. [1] https://bugzilla.kernel.org/show_bug.cgi?id=203967 Suggested-by: Dmitry Vyukov Suggested-by: Walter Wu Suggested-by: Andrey Ryabinin Suggested-by: Kirill A. Shutemov Signed-off-by: Vlastimil Babka --- .../admin-guide/kernel-parameters.txt | 8 ++ Documentation/dev-tools/kasan.rst | 3 + include/linux/page_owner.h | 1 + mm/page_ext.c | 1 + mm/page_owner.c | 90 +++++++++++++------ 5 files changed, 78 insertions(+), 25 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 944e03e29f65..14dcb66e3457 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3237,6 +3237,14 @@ we can turn it on. on: enable the feature + page_owner_free= + [KNL] When enabled together with page_owner, store also + the stack of who frees a page, for error page dump + purposes. This is also implicitly enabled by + debug_pagealloc=on or KASAN, so only page_owner=on is + sufficient in those cases. + on: enable the feature + page_poison= [KNL] Boot-time parameter changing the state of poisoning on the buddy allocator, available with CONFIG_PAGE_POISONING=y. diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index b72d07d70239..525296121d89 100644 --- a/Documentation/dev-tools/kasan.rst +++ b/Documentation/dev-tools/kasan.rst @@ -41,6 +41,9 @@ smaller binary while the latter is 1.1 - 2 times faster. Both KASAN modes work with both SLUB and SLAB memory allocators. For better bug detection and nicer reporting, enable CONFIG_STACKTRACE. +To augment reports with last allocation and freeing stack of the physical page, +it is recommended to enable also CONFIG_PAGE_OWNER and boot with page_owner=on. + To disable instrumentation for specific files or directories, add a line similar to the following to the respective kernel Makefile: diff --git a/include/linux/page_owner.h b/include/linux/page_owner.h index 8679ccd722e8..0888dd70cc61 100644 --- a/include/linux/page_owner.h +++ b/include/linux/page_owner.h @@ -7,6 +7,7 @@ #ifdef CONFIG_PAGE_OWNER extern struct static_key_false page_owner_inited; extern struct page_ext_operations page_owner_ops; +extern struct page_ext_operations page_owner_free_ops; extern void __reset_page_owner(struct page *page, unsigned int order); extern void __set_page_owner(struct page *page, diff --git a/mm/page_ext.c b/mm/page_ext.c index 4ade843ff588..5724b637939a 100644 --- a/mm/page_ext.c +++ b/mm/page_ext.c @@ -61,6 +61,7 @@ static struct page_ext_operations *page_ext_ops[] = { #ifdef CONFIG_PAGE_OWNER &page_owner_ops, + &page_owner_free_ops, #endif #if defined(CONFIG_IDLE_PAGE_TRACKING) && !defined(CONFIG_64BIT) &page_idle_ops, diff --git a/mm/page_owner.c b/mm/page_owner.c index d3cf5d336ccf..a668a735b9b6 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -24,13 +24,16 @@ struct page_owner { short last_migrate_reason; gfp_t gfp_mask; depot_stack_handle_t handle; -#ifdef CONFIG_DEBUG_PAGEALLOC +}; + +struct page_owner_free { depot_stack_handle_t free_handle; -#endif }; -static bool page_owner_disabled = true; +static bool page_owner_enabled = false; +static bool page_owner_free_enabled = false; DEFINE_STATIC_KEY_FALSE(page_owner_inited); +static DEFINE_STATIC_KEY_FALSE(page_owner_free_stack); static depot_stack_handle_t dummy_handle; static depot_stack_handle_t failure_handle; @@ -44,7 +47,7 @@ static int __init early_page_owner_param(char *buf) return -EINVAL; if (strcmp(buf, "on") == 0) - page_owner_disabled = false; + page_owner_enabled = true; return 0; } @@ -52,10 +55,30 @@ early_param("page_owner", early_page_owner_param); static bool need_page_owner(void) { - if (page_owner_disabled) + return page_owner_enabled; +} + +static int __init early_page_owner_free_param(char *buf) +{ + if (!buf) + return -EINVAL; + + if (strcmp(buf, "on") == 0) + page_owner_free_enabled = true; + + return 0; +} +early_param("page_owner_free", early_page_owner_free_param); + +static bool need_page_owner_free(void) { + + if (!page_owner_enabled) return false; - return true; + if (IS_ENABLED(CONFIG_KASAN) || debug_pagealloc_enabled()) + page_owner_free_enabled = true; + + return page_owner_free_enabled; } static __always_inline depot_stack_handle_t create_dummy_stack(void) @@ -84,7 +107,7 @@ static noinline void register_early_stack(void) static void init_page_owner(void) { - if (page_owner_disabled) + if (!page_owner_enabled) return; register_dummy_stack(); @@ -94,17 +117,36 @@ static void init_page_owner(void) init_early_allocated_pages(); } +static void init_page_owner_free(void) +{ + if (!page_owner_enabled || !page_owner_free_enabled) + return; + + static_branch_enable(&page_owner_free_stack); +} + struct page_ext_operations page_owner_ops = { .size = sizeof(struct page_owner), .need = need_page_owner, .init = init_page_owner, }; +struct page_ext_operations page_owner_free_ops = { + .size = sizeof(struct page_owner_free), + .need = need_page_owner_free, + .init = init_page_owner_free, +}; + static inline struct page_owner *get_page_owner(struct page_ext *page_ext) { return (void *)page_ext + page_owner_ops.offset; } +static inline struct page_owner_free *get_page_owner_free(struct page_ext *page_ext) +{ + return (void *)page_ext + page_owner_free_ops.offset; +} + static inline bool check_recursive_alloc(unsigned long *entries, unsigned int nr_entries, unsigned long ip) @@ -148,25 +190,21 @@ void __reset_page_owner(struct page *page, unsigned int order) { int i; struct page_ext *page_ext; -#ifdef CONFIG_DEBUG_PAGEALLOC depot_stack_handle_t handle = 0; - struct page_owner *page_owner; + struct page_owner_free *page_owner_free; - if (debug_pagealloc_enabled()) + if (static_branch_unlikely(&page_owner_free_stack)) handle = save_stack(GFP_NOWAIT | __GFP_NOWARN); -#endif page_ext = lookup_page_ext(page); if (unlikely(!page_ext)) return; for (i = 0; i < (1 << order); i++) { __clear_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags); -#ifdef CONFIG_DEBUG_PAGEALLOC - if (debug_pagealloc_enabled()) { - page_owner = get_page_owner(page_ext); - page_owner->free_handle = handle; + if (static_branch_unlikely(&page_owner_free_stack)) { + page_owner_free = get_page_owner_free(page_ext); + page_owner_free->free_handle = handle; } -#endif page_ext = page_ext_next(page_ext); } } @@ -414,6 +452,7 @@ void __dump_page_owner(struct page *page) { struct page_ext *page_ext = lookup_page_ext(page); struct page_owner *page_owner; + struct page_owner_free *page_owner_free; depot_stack_handle_t handle; unsigned long *entries; unsigned int nr_entries; @@ -450,16 +489,17 @@ void __dump_page_owner(struct page *page) stack_trace_print(entries, nr_entries, 0); } -#ifdef CONFIG_DEBUG_PAGEALLOC - handle = READ_ONCE(page_owner->free_handle); - if (!handle) { - pr_alert("page_owner free stack trace missing\n"); - } else { - nr_entries = stack_depot_fetch(handle, &entries); - pr_alert("page last free stack trace:\n"); - stack_trace_print(entries, nr_entries, 0); + if (static_branch_unlikely(&page_owner_free_stack)) { + page_owner_free = get_page_owner_free(page_ext); + handle = READ_ONCE(page_owner_free->free_handle); + if (!handle) { + pr_alert("page_owner free stack trace missing\n"); + } else { + nr_entries = stack_depot_fetch(handle, &entries); + pr_alert("page last free stack trace:\n"); + stack_trace_print(entries, nr_entries, 0); + } } -#endif if (page_owner->last_migrate_reason != -1) pr_alert("page has been migrated, last migrate reason: %s\n", From patchwork Mon Sep 30 12:29:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vlastimil Babka X-Patchwork-Id: 11166581 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 1A5AE1599 for ; Mon, 30 Sep 2019 12:29:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E5D1720815 for ; Mon, 30 Sep 2019 12:29:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E5D1720815 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 1B4666B0006; Mon, 30 Sep 2019 08:29:32 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 16DF86B0007; Mon, 30 Sep 2019 08:29:32 -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 004716B0007; Mon, 30 Sep 2019 08:29:31 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0072.hostedemail.com [216.40.44.72]) by kanga.kvack.org (Postfix) with ESMTP id D51846B0006 for ; Mon, 30 Sep 2019 08:29:31 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id 815D5812F for ; Mon, 30 Sep 2019 12:29:31 +0000 (UTC) X-FDA: 75991517742.27.rule31_5313a82124239 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,vbabka@suse.cz,:akpm@linux-foundation.org::linux-kernel@vger.kernel.org:kasan-dev@googlegroups.com:cai@lca.pw:kirill.shutemov@linux.intel.com:willy@infradead.org:mgorman@techsingularity.net:mhocko@kernel.org:vbabka@suse.cz:kirill@shutemov.name,RULES_HIT:30051:30054:30070:30075,0,RBL:195.135.220.15:@suse.cz:.lbl8.mailshell.net-62.2.6.2 64.100.201.201,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,LFtime:25,LUA_SUMMARY:none X-HE-Tag: rule31_5313a82124239 X-Filterd-Recvd-Size: 4566 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf17.hostedemail.com (Postfix) with ESMTP for ; Mon, 30 Sep 2019 12:29:30 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id D51D0AEF1; Mon, 30 Sep 2019 12:29:28 +0000 (UTC) From: Vlastimil Babka To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, Qian Cai , "Kirill A. Shutemov" , Matthew Wilcox , Mel Gorman , Michal Hocko , Vlastimil Babka , "Kirill A . Shutemov" Subject: [PATCH v2 3/3] mm, page_owner: rename flag indicating that page is allocated Date: Mon, 30 Sep 2019 14:29:16 +0200 Message-Id: <20190930122916.14969-4-vbabka@suse.cz> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190930122916.14969-1-vbabka@suse.cz> References: <20190930122916.14969-1-vbabka@suse.cz> 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: Commit 37389167a281 ("mm, page_owner: keep owner info when freeing the page") has introduced a flag PAGE_EXT_OWNER_ACTIVE to indicate that page is tracked as being allocated. Kirril suggested naming it PAGE_EXT_OWNER_ALLOCATED to make it more clear, as "active is somewhat loaded term for a page". Suggested-by: Kirill A. Shutemov Signed-off-by: Vlastimil Babka --- include/linux/page_ext.h | 2 +- mm/page_owner.c | 12 ++++++------ 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h index 5e856512bafb..cfce186f0c4e 100644 --- a/include/linux/page_ext.h +++ b/include/linux/page_ext.h @@ -18,7 +18,7 @@ struct page_ext_operations { enum page_ext_flags { PAGE_EXT_OWNER, - PAGE_EXT_OWNER_ACTIVE, + PAGE_EXT_OWNER_ALLOCATED, #if defined(CONFIG_IDLE_PAGE_TRACKING) && !defined(CONFIG_64BIT) PAGE_EXT_YOUNG, PAGE_EXT_IDLE, diff --git a/mm/page_owner.c b/mm/page_owner.c index a668a735b9b6..55f60ae2b6f8 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -200,7 +200,7 @@ void __reset_page_owner(struct page *page, unsigned int order) if (unlikely(!page_ext)) return; for (i = 0; i < (1 << order); i++) { - __clear_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags); + __clear_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags); if (static_branch_unlikely(&page_owner_free_stack)) { page_owner_free = get_page_owner_free(page_ext); page_owner_free->free_handle = handle; @@ -223,7 +223,7 @@ static inline void __set_page_owner_handle(struct page *page, page_owner->gfp_mask = gfp_mask; page_owner->last_migrate_reason = -1; __set_bit(PAGE_EXT_OWNER, &page_ext->flags); - __set_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags); + __set_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags); page_ext = page_ext_next(page_ext); } @@ -297,7 +297,7 @@ void __copy_page_owner(struct page *oldpage, struct page *newpage) * the new page, which will be freed. */ __set_bit(PAGE_EXT_OWNER, &new_ext->flags); - __set_bit(PAGE_EXT_OWNER_ACTIVE, &new_ext->flags); + __set_bit(PAGE_EXT_OWNER_ALLOCATED, &new_ext->flags); } void pagetypeinfo_showmixedcount_print(struct seq_file *m, @@ -357,7 +357,7 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m, if (unlikely(!page_ext)) continue; - if (!test_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags)) + if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) continue; page_owner = get_page_owner(page_ext); @@ -473,7 +473,7 @@ void __dump_page_owner(struct page *page) return; } - if (test_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags)) + if (test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) pr_alert("page_owner tracks the page as allocated\n"); else pr_alert("page_owner tracks the page as freed\n"); @@ -566,7 +566,7 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) * Although we do have the info about past allocation of free * pages, it's not relevant for current memory usage. */ - if (!test_bit(PAGE_EXT_OWNER_ACTIVE, &page_ext->flags)) + if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) continue; page_owner = get_page_owner(page_ext);