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=-8.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 35F68C433ED for ; Mon, 5 Apr 2021 03:03:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4CC4B61391 for ; Mon, 5 Apr 2021 03:03:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4CC4B61391 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 57FBF6B0073; Sun, 4 Apr 2021 23:03:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 556236B0075; Sun, 4 Apr 2021 23:03:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3F71A6B0078; Sun, 4 Apr 2021 23:03:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0114.hostedemail.com [216.40.44.114]) by kanga.kvack.org (Postfix) with ESMTP id 21E196B0073 for ; Sun, 4 Apr 2021 23:03:45 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id BF0C4E087 for ; Mon, 5 Apr 2021 03:03:44 +0000 (UTC) X-FDA: 77996818368.07.1232D9D Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf25.hostedemail.com (Postfix) with ESMTP id 1F9DE600010B for ; Mon, 5 Apr 2021 03:03:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=8niou5aICcGIn04FGvkF6VvV0aedpzsCU/1XAKhfOVk=; b=pflt2+8Zk/XZtxBwvWQj+/7DPu 7angM1JbN2z5VI6VFT8nKRE/tb2cAZ6JqYRtBmwkLmmgeD1p0j3Bx+u0dDGLHJtD/nJGgaiIf+2QI fB89YB27uDyQ2JQRpiuIVbqgx4Uk6bG/F1pHMcEzFTEzV2r5T3LJbnuCrzeTmOk9B+xGLHpv4eLYv 9U8ifNvDTPYfbx7Xt8wYV26+CA59r3VXofDd3dL/6kN5MSTSZaA/JYCm8Jk/zJrCEosmsZrWhwcQP C6NPGKb7c/kBN9z8YU4PCDJAxTrUAC99/BAB5BmE6M2fmfTtzYuN6t+ZzNpMwRxsm/C9chhTA9ZSf uDNHv0tw==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lTFWU-00Ar3w-Sb; Mon, 05 Apr 2021 03:03:33 +0000 Date: Mon, 5 Apr 2021 04:03:30 +0100 From: Matthew Wilcox To: syzbot Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] WARNING: suspicious RCU usage in clear_huge_page Message-ID: <20210405030330.GD2531743@casper.infradead.org> References: <0000000000006e0a8405bf1c6e8e@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0000000000006e0a8405bf1c6e8e@google.com> X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 1F9DE600010B X-Stat-Signature: upx6rnkkhkw15e77yfbipnuoidu5g1gj Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf25; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617591823-291079 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: #syz dup: WARNING: suspicious RCU usage in getname_flags On Sat, Apr 03, 2021 at 07:35:16PM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: d19cc4bf Merge tag 'trace-v5.12-rc5' of git://git.kernel.o.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1611e681d00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=78ef1d159159890 > dashboard link: https://syzkaller.appspot.com/bug?extid=7a0c25f9520c969c15f5 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+7a0c25f9520c969c15f5@syzkaller.appspotmail.com > > ============================= > WARNING: suspicious RCU usage > 5.12.0-rc5-syzkaller #0 Not tainted > ----------------------------- > kernel/sched/core.c:8294 Illegal context switch in RCU-bh read-side critical section! > > other info that might help us debug this: > > > rcu_scheduler_active = 2, debug_locks = 0 > 1 lock held by syz-executor.2/10002: > #0: ffff8880129669d8 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] > #0: ffff8880129669d8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x285/0x1210 arch/x86/mm/fault.c:1331 > > stack backtrace: > CPU: 0 PID: 10002 Comm: syz-executor.2 Not tainted 5.12.0-rc5-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:79 [inline] > dump_stack+0x141/0x1d7 lib/dump_stack.c:120 > ___might_sleep+0x229/0x2c0 kernel/sched/core.c:8294 > process_huge_page mm/memory.c:5051 [inline] > clear_huge_page+0x9c/0x560 mm/memory.c:5112 > __do_huge_pmd_anonymous_page mm/huge_memory.c:607 [inline] > do_huge_pmd_anonymous_page+0x60e/0x2570 mm/huge_memory.c:772 > create_huge_pmd mm/memory.c:4189 [inline] > __handle_mm_fault+0x2e59/0x4f70 mm/memory.c:4424 > handle_mm_fault+0x1bc/0x7e0 mm/memory.c:4551 > do_user_addr_fault+0x483/0x1210 arch/x86/mm/fault.c:1390 > handle_page_fault arch/x86/mm/fault.c:1475 [inline] > exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1531 > asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577 > RIP: 0033:0x461b6d > Code: 48 01 d0 eb 0b 0f 1f 84 00 00 00 00 00 48 89 f8 48 83 fa 20 72 49 48 83 fa 40 0f 87 9f 00 00 00 c5 fe 6f 06 c5 fe 6f 4c 16 e0 fe 7f 07 c5 fe 7f 4c 17 e0 c5 f8 77 c3 48 3b 15 7e 8e 04 01 0f > RSP: 002b:00007fffc28c60c8 EFLAGS: 00010287 > RAX: 0000000020000080 RBX: 0000000000000003 RCX: 0000000000570000 > RDX: 000000000000002b RSI: 0000000000570020 RDI: 0000000020000080 > RBP: 00007fffc28c6188 R08: 0000000000970000 R09: 00007fffc2907090 > R10: 000000000000a8e8 R11: 0000000000000000 R12: 0000000000000001 > R13: 0000000000000000 R14: 000000000056bf60 R15: 0000000000035790 > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. >