From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f197.google.com (mail-il1-f197.google.com [209.85.166.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7073078289 for ; Sat, 30 Nov 2024 19:22:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732994550; cv=none; b=mr6MC6SKdvcrQgWM4tYJqiSIJNWw4Ssn0ph+RUStJJHieKtl3GtNeUBCXvY/qbDakCFme4coB5PWVcH+D9MtYMImoGdq5p+YH2hLMtnOOWFjblTMVhGot1t6EQSehbnHEyMiCx75uXYOvzzvKRAwvuPyFn18NBkyacV2ahtxkkA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732994550; c=relaxed/simple; bh=31/CFZJlEL6qa7SlVx8LTH8YQhk/9E3WSjuzplrxkgg=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=MXOsPdMnpE9M4NnFIkC2I/TnSIrA2IiM82YuuiXyWyNzLkwmdWxX1YTIjFOreD9EFaNXX+cKMf+EOZIOk0nbc+C5jf50YcOjg5H+HEj0y3gOc12zQcDpFS/T9PPRu4+RTUyJYW50UZVu8H3EgOy1NM6rW6emWI9QwERcnnO77Tk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f197.google.com with SMTP id e9e14a558f8ab-3a7cf41b54eso54242805ab.2 for ; Sat, 30 Nov 2024 11:22:28 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1732994547; x=1733599347; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=25b4GeI0ihUnJKqCXa6ULDLb7C7s6hytPp3kKo7gqYA=; b=DHGmK88kAdyToYzU/qjHE3nKhmMPUl/6122mHFZQBhtYtJ3FwaRUkN5SINVEeN40S6 IThpKpmJDouVPOd2x9C4nfZJav1rEAtFYeHAZ38DL6WZDmnC0D1uycjzAgRuokTnUz0j 45hVFakzwmN7z0KHbi26PeAp81tSEKv5eHaRRa8tc/jg6Ra7MRXYWHRd1ZWH43dAvrX0 cubQzpB9RovHEvgnF30JBgsnkpJOc0aFC46ODWkEO31AECqNoB9X5ts6SN8QFzsNN1sx kP1sYEUzh6Qv6EwbQ+BCyMz/WnxYzadtFBXuJ8uuuL5h08WQp7Tz+QDXg9R5X21jS9xM T+AA== X-Forwarded-Encrypted: i=1; AJvYcCUeCRdnZztwXc5ipFIukIidsavCFyn+PZdtNZN5xmfakJkm2kedTLmgiOULAXgUwFfvKeKf8m8x3ndIaWE=@vger.kernel.org X-Gm-Message-State: AOJu0YwFUAX1/EH5z721O0IZnpTZIFDBtCdUDMRwQDMICsO7V+Xzafcx hySS5jhrKENfL0UEt8MTxjYX0xY/IUH4MEbAxN++T+u1a97BJVjfT3gbyGKrDKBszp88qLX3bYo r2eXJAVwA6byydrBTH2RtXU/V4xz0N5rmLFLZQvOybD9U9vIaqhKZwx8= X-Google-Smtp-Source: AGHT+IEr2049YLIAJA3B/LRrjfhDvbrO1YvkdyhX6qWhqbv9n0J85JObyoYfM8NTB9Rc4ceSSfV6DyfigqUh+RoMqCYL9L/Pc7MB Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1d9a:b0:3a7:d7dd:e70f with SMTP id e9e14a558f8ab-3a7d7dde9dcmr63988935ab.12.1732994547648; Sat, 30 Nov 2024 11:22:27 -0800 (PST) Date: Sat, 30 Nov 2024 11:22:27 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <674b65f3.050a0220.253251.00e1.GAE@google.com> Subject: [syzbot] [block?] possible deadlock in elevator_disable From: syzbot To: axboe@kernel.dk, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 7eef7e306d3c Merge tag 'for-6.13/dm-changes' of git://git... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17c2cf5f980000 kernel config: https://syzkaller.appspot.com/x/.config?x=8df9bf3383f5970 dashboard link: https://syzkaller.appspot.com/bug?extid=dbad16606916438a362a compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/ea7fc4bd274d/disk-7eef7e30.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2b75212b0174/vmlinux-7eef7e30.xz kernel image: https://storage.googleapis.com/syzbot-assets/f1ab50706485/bzImage-7eef7e30.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+dbad16606916438a362a@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.12.0-syzkaller-09567-g7eef7e306d3c #0 Not tainted ------------------------------------------------------ syz.3.433/7118 is trying to acquire lock: ffff888025a200b8 (&eq->sysfs_lock){+.+.}-{4:4}, at: elevator_exit block/elevator.c:158 [inline] ffff888025a200b8 (&eq->sysfs_lock){+.+.}-{4:4}, at: elevator_disable+0xd3/0x3f0 block/elevator.c:674 but task is already holding lock: ffff8880256fdde0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4847 [inline] ffff8880256fdde0 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:4925 [inline] ffff8880256fdde0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x3fa/0x1ae0 block/blk-mq.c:4985 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&q->sysfs_lock){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_mq_elv_switch_none block/blk-mq.c:4847 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:4925 [inline] blk_mq_update_nr_hw_queues+0x3fa/0x1ae0 block/blk-mq.c:4985 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&q->q_usage_counter(io)#53){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x23a0 block/blk-mq.c:3092 __submit_bio+0x2c6/0x560 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2446 filemap_read_folio+0x14b/0x630 mm/filemap.c:2366 filemap_update_page mm/filemap.c:2450 [inline] filemap_get_pages+0x17af/0x2540 mm/filemap.c:2571 filemap_read+0x45c/0xf50 mm/filemap.c:2646 blkdev_read_iter+0x2d8/0x430 block/fops.c:767 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x991/0xb70 fs/read_write.c:565 ksys_read+0x18f/0x2b0 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (mapping.invalidate_lock#2){.+.+}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:873 [inline] filemap_fault+0x6e8/0x1950 mm/filemap.c:3332 __do_fault+0x135/0x460 mm/memory.c:4907 do_shared_fault mm/memory.c:5386 [inline] do_fault mm/memory.c:5460 [inline] do_pte_missing mm/memory.c:3979 [inline] handle_pte_fault+0x1140/0x68a0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6112 faultin_page mm/gup.c:1187 [inline] __get_user_pages+0x1c82/0x49e0 mm/gup.c:1485 __get_user_pages_locked mm/gup.c:1751 [inline] faultin_page_range+0x4e7/0x850 mm/gup.c:1975 madvise_populate mm/madvise.c:951 [inline] do_madvise+0x6e5/0x4d10 mm/madvise.c:1681 __do_sys_madvise mm/madvise.c:1700 [inline] __se_sys_madvise mm/madvise.c:1698 [inline] __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1698 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&mm->mmap_lock ){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __might_fault+0xc6/0x120 mm/memory.c:6751 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x2a/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] __blk_trace_setup kernel/trace/blktrace.c:626 [inline] blk_trace_ioctl+0x1ad/0x9a0 kernel/trace/blktrace.c:740 blkdev_ioctl+0x40c/0x6a0 block/ioctl.c:682 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 ( &q->debugfs_mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_mq_exit_sched+0x106/0x4a0 block/blk-mq-sched.c:531 elevator_exit block/elevator.c:159 [inline] elevator_disable+0xde/0x3f0 block/elevator.c:674 blk_mq_elv_switch_none block/blk-mq.c:4861 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:4925 [inline] blk_mq_update_nr_hw_queues+0x646/0x1ae0 block/blk-mq.c:4985 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 ( &eq->sysfs_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 elevator_exit block/elevator.c:158 [inline] elevator_disable+0xd3/0x3f0 block/elevator.c:674 blk_mq_elv_switch_none block/blk-mq.c:4861 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:4925 [inline] blk_mq_update_nr_hw_queues+0x646/0x1ae0 block/blk-mq.c:4985 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &eq->sysfs_lock --> &q->q_usage_counter(io)#53 --> &q->sysfs_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->sysfs_lock); lock(&q->q_usage_counter(io)#53); lock(&q->sysfs_lock); lock(&eq->sysfs_lock); *** DEADLOCK *** 5 locks held by syz.3.433/7118: #0: ffff8880258dc198 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x13c/0xf40 drivers/block/nbd.c:1572 #1: ffff8880258dc0d8 (&set->tag_list_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0xc2/0x1ae0 block/blk-mq.c:4984 #2: ffff8880256fd8b0 (&q->q_usage_counter(io)#52){+.+.}-{0:0}, at: nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 #3: ffff8880256fd8e8 (&q->q_usage_counter(queue)#36){+.+.}-{0:0}, at: nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 #4: ffff8880256fdde0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4847 [inline] #4: ffff8880256fdde0 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:4925 [inline] #4: ffff8880256fdde0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x3fa/0x1ae0 block/blk-mq.c:4985 stack backtrace: CPU: 0 UID: 0 PID: 7118 Comm: syz.3.433 Not tainted 6.12.0-syzkaller-09567-g7eef7e306d3c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 elevator_exit block/elevator.c:158 [inline] elevator_disable+0xd3/0x3f0 block/elevator.c:674 blk_mq_elv_switch_none block/blk-mq.c:4861 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:4925 [inline] blk_mq_update_nr_hw_queues+0x646/0x1ae0 block/blk-mq.c:4985 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5d32580809 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5d333ec058 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5d32745fa0 RCX: 00007f5d32580809 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007f5d325f393e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5d32745fa0 R15: 00007ffd8ba200a8 --- 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. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup