From patchwork Fri Dec 11 01:20:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 11966979 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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,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 2D929C4167B for ; Fri, 11 Dec 2020 01:20:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D20DF23E23 for ; Fri, 11 Dec 2020 01:20:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D20DF23E23 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 299D06B005D; Thu, 10 Dec 2020 20:20:08 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 24C4E6B0070; Thu, 10 Dec 2020 20:20:08 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ED9956B0072; Thu, 10 Dec 2020 20:20:07 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0230.hostedemail.com [216.40.44.230]) by kanga.kvack.org (Postfix) with ESMTP id BC4E36B0070 for ; Thu, 10 Dec 2020 20:20:07 -0500 (EST) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 887651E1F for ; Fri, 11 Dec 2020 01:20:07 +0000 (UTC) X-FDA: 77579245254.14.owl34_5311514273fc Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id 6D90218229837 for ; Fri, 11 Dec 2020 01:20:07 +0000 (UTC) X-HE-Tag: owl34_5311514273fc X-Filterd-Recvd-Size: 4210 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf08.hostedemail.com (Postfix) with ESMTP for ; Fri, 11 Dec 2020 01:20:06 +0000 (UTC) From: paulmck@kernel.org Authentication-Results: mail.kernel.org; dkim=permerror (bad message/signature format) To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, iamjoonsoo.kim@lge.com, andrii@kernel.org, "Paul E. McKenney" , linux-mm@kvack.org Subject: [PATCH v3 sl-b 3/6] mm: Make mem_dump_obj() handle vmalloc() memory Date: Thu, 10 Dec 2020 17:20:00 -0800 Message-Id: <20201211012003.16473-3-paulmck@kernel.org> X-Mailer: git-send-email 2.9.5 In-Reply-To: <20201211011907.GA16110@paulmck-ThinkPad-P72> References: <20201211011907.GA16110@paulmck-ThinkPad-P72> 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: "Paul E. McKenney" This commit adds vmalloc() support to mem_dump_obj(). Note that the vmalloc_dump_obj() function combines the checking and dumping, in contrast with the split between kmem_valid_obj() and kmem_dump_obj(). The reason for the difference is that the checking in the vmalloc() case involves acquiring a global lock, and redundant acquisitions of global locks should be avoided, even on not-so-fast paths. Note that this change causes on-stack variables to be reported as vmalloc() storage from kernel_clone() or similar, depending on the degree of inlining that your compiler does. This is likely more helpful than the earlier "non-paged (local) memory". Cc: Andrew Morton Cc: Joonsoo Kim Cc: Reported-by: Andrii Nakryiko Signed-off-by: Paul E. McKenney --- include/linux/vmalloc.h | 6 ++++++ mm/util.c | 14 ++++++++------ mm/vmalloc.c | 12 ++++++++++++ 3 files changed, 26 insertions(+), 6 deletions(-) diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 938eaf9..c89c2be 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -248,4 +248,10 @@ pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) int register_vmap_purge_notifier(struct notifier_block *nb); int unregister_vmap_purge_notifier(struct notifier_block *nb); +#ifdef CONFIG_MMU +bool vmalloc_dump_obj(void *object); +#else +static inline bool vmalloc_dump_obj(void *object) { return false; } +#endif + #endif /* _LINUX_VMALLOC_H */ diff --git a/mm/util.c b/mm/util.c index f7c94c8..dcde696 100644 --- a/mm/util.c +++ b/mm/util.c @@ -984,18 +984,20 @@ int __weak memcmp_pages(struct page *page1, struct page *page2) */ void mem_dump_obj(void *object) { + if (kmem_valid_obj(object)) { + kmem_dump_obj(object); + return; + } + if (vmalloc_dump_obj(object)) + return; if (!virt_addr_valid(object)) { if (object == NULL) pr_cont(" NULL pointer.\n"); else if (object == ZERO_SIZE_PTR) pr_cont(" zero-size pointer.\n"); else - pr_cont(" non-paged (local) memory.\n"); - return; - } - if (kmem_valid_obj(object)) { - kmem_dump_obj(object); + pr_cont(" non-paged memory.\n"); return; } - pr_cont(" non-slab memory.\n"); + pr_cont(" non-slab/vmalloc memory.\n"); } diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 6ae491a..7421719 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -3431,6 +3431,18 @@ void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) } #endif /* CONFIG_SMP */ +bool vmalloc_dump_obj(void *object) +{ + struct vm_struct *vm; + void *objp = (void *)PAGE_ALIGN((unsigned long)object); + + vm = find_vm_area(objp); + if (!vm) + return false; + pr_cont(" vmalloc allocated at %pS\n", vm->caller); + return true; +} + #ifdef CONFIG_PROC_FS static void *s_start(struct seq_file *m, loff_t *pos) __acquires(&vmap_purge_lock)