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=-8.7 required=3.0 tests=BAYES_00,FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 39F15C433E0 for ; Fri, 19 Mar 2021 09:45:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B9F164EE2 for ; Fri, 19 Mar 2021 09:45:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229519AbhCSJpZ (ORCPT ); Fri, 19 Mar 2021 05:45:25 -0400 Received: from mail-il1-f200.google.com ([209.85.166.200]:37860 "EHLO mail-il1-f200.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229766AbhCSJpU (ORCPT ); Fri, 19 Mar 2021 05:45:20 -0400 Received: by mail-il1-f200.google.com with SMTP id a14so15879479ilj.4 for ; Fri, 19 Mar 2021 02:45:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=GKPXbiVNuIwQHsRuMAbWdUTxkPnfWdxXiRjOZg6AQ8o=; b=R/aI/VDHlGIWm17hg6AKHcdN9ZxIoyPVWZXmLKQt0CVPweLyiRmKRxrwlFvfh1wxfa ejK8XMDnfU2tfYKawjUCuRVbEBUc48VOTVKszzJQTZiOxyITcMoHAeqOD02byXF2alz1 46W5hk9YjoyVrQG08Pf2jqNIV7wz0lTG0qskimPQu3e5+lM4fX4tbRDxVVa6DNatyZcD AT6y6L9buOKre0AOHv52skg0LNdG6/pzY/KXLS8tX54PWpa7GA0iw+WGLVUK7xfM6EJw u9IHh0qeqm40+XkslC4zx20ThuWuKFKqLETwRNdDQvVJod85DyRl43ZK6UZyEekWR2vx ssxw== X-Gm-Message-State: AOAM532jZK6GLX25y5kk6K89Op8mCh5Y6MB8czfqfoYzAHTErREo3aVh Uf43zrFj+Vk4sMGoFIsWu1syZJQQrnAGUAL0oPo97O2lgIB/ X-Google-Smtp-Source: ABdhPJzFsa8iygFbN7hXAnw0CQ8QrVL80j/Moe3pG4vWZO4TIsqy8BNsvqV6wI+wIxFnNVAI9mM6pRVrRHC7Hu2Ls5SXJl3Ra17u MIME-Version: 1.0 X-Received: by 2002:a05:6602:14cb:: with SMTP id b11mr2114361iow.175.1616147119654; Fri, 19 Mar 2021 02:45:19 -0700 (PDT) Date: Fri, 19 Mar 2021 02:45:19 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000f8ca3305bde0922e@google.com> Subject: [syzbot] WARNING in percpu_ref_exit (3) From: syzbot To: asml.silence@gmail.com, axboe@kernel.dk, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Hello, syzbot found the following issue on: HEAD commit: bf152b0b Merge tag 'for_linus' of git://git.kernel.org/pub.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14532c1ad00000 kernel config: https://syzkaller.appspot.com/x/.config?x=e2f52d48cfe68458 dashboard link: https://syzkaller.appspot.com/bug?extid=fedc0f6148b1b9a42593 compiler: Debian clang version 11.0.1-2 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+fedc0f6148b1b9a42593@syzkaller.appspotmail.com ------------[ cut here ]------------ WARNING: CPU: 0 PID: 68 at lib/percpu-refcount.c:113 __percpu_ref_exit lib/percpu-refcount.c:113 [inline] WARNING: CPU: 0 PID: 68 at lib/percpu-refcount.c:113 percpu_ref_exit+0x1e0/0x1f0 lib/percpu-refcount.c:134 Modules linked in: CPU: 1 PID: 68 Comm: kworker/u4:2 Not tainted 5.12.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound io_ring_exit_work RIP: 0010:__percpu_ref_exit lib/percpu-refcount.c:113 [inline] RIP: 0010:percpu_ref_exit+0x1e0/0x1f0 lib/percpu-refcount.c:134 Code: c7 c7 80 67 ce 8c 4c 89 e6 e8 9c 96 84 05 48 8b 3c 24 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d e9 65 8b e8 fd e8 00 68 a5 fd <0f> 0b e9 d0 fe ff ff 66 0f 1f 84 00 00 00 00 00 41 57 41 56 41 55 RSP: 0018:ffffc90000fbfba0 EFLAGS: 00010293 RAX: ffffffff83d35710 RBX: 0000607f46034a90 RCX: ffff88801195b780 RDX: 0000000000000000 RSI: 0000607f46034a90 RDI: 0000000000000000 RBP: ffff8880292ae580 R08: ffffffff83d355a5 R09: fffffbfff1f290ca R10: fffffbfff1f290ca R11: 0000000000000000 R12: ffff8880292ae590 R13: ffff8880121a6000 R14: 1ffff11002434c00 R15: 1ffff11002434c01 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32d23000 CR3: 0000000013897000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: io_ring_ctx_free fs/io_uring.c:8419 [inline] io_ring_exit_work+0x580/0xa90 fs/io_uring.c:8565 process_one_work+0x789/0xfd0 kernel/workqueue.c:2275 worker_thread+0xac1/0x1300 kernel/workqueue.c:2421 kthread+0x39a/0x3c0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 --- 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.