From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot0-f198.google.com (mail-ot0-f198.google.com [74.125.82.198]) by kanga.kvack.org (Postfix) with ESMTP id 622366B0003 for ; Mon, 11 Jun 2018 06:57:19 -0400 (EDT) Received: by mail-ot0-f198.google.com with SMTP id w15-v6so4471384otk.12 for ; Mon, 11 Jun 2018 03:57:19 -0700 (PDT) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [202.181.97.72]) by mx.google.com with ESMTPS id j41-v6si11691356otb.287.2018.06.11.03.57.17 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 11 Jun 2018 03:57:18 -0700 (PDT) Subject: Re: INFO: task hung in collapse_huge_page References: <000000000000a6d200056b14bfd4@google.com> From: Tetsuo Handa Message-ID: Date: Mon, 11 Jun 2018 19:56:34 +0900 MIME-Version: 1.0 In-Reply-To: <000000000000a6d200056b14bfd4@google.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: syzbot , syzkaller-bugs@googlegroups.com Cc: akpm@linux-foundation.org, gregkh@linuxfoundation.org, hannes@cmpxchg.org, kirill.shutemov@linux.intel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.com, rientjes@google.com, shli@fb.com, sj38.park@gmail.com, willy@infradead.org, yang.s@alibaba-inc.com khugepaged is trying to hold mm->mmap_sem for write, which is held for read by a thread which is stuck at __sb_start_write(). Therefore, #syz dup: INFO: task hung in __sb_start_write