From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f206.google.com (mail-il1-f206.google.com [209.85.166.206]) (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 2952E217701 for ; Thu, 26 Jun 2025 10:05:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750932337; cv=none; b=fd2hpAePuvcvAD+rcCiXYahSZ6vE6nGD6vvIzA6XC+myF/xHIiw8/6BASPV0Hqur3ufi+Vx3hPRx+ZPnRsvRbJNsSp8XhAyb95mKPwB+yaPDtaAzfXY2p8AsSGRBA3QBfH4wJg1VWUu5FtCGZJe4UQuQJFvvm4W5pumWZARhTms= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750932337; c=relaxed/simple; bh=hqp5iWXg7QS0Zu8cF4dv50I19ymXxkRKzOhSmGn++Vw=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=BhkDOKZH+klvo0HZfpj5O2PkClKTpPqgkCSwzPrPnBdAKPme9YeNN7+qP9KU/bDxy/m6NUcxUoFgbTm3oQ1kljpbeSD6YLf4ZoilcAzH/DVyqdLF7i8awkO//xn2YtGQRjAN2gVJwLIF+3ViOaUJD0iY0wIa4D+s+1FCHc+HkkE= 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=209.85.166.206 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-f206.google.com with SMTP id e9e14a558f8ab-3ddb4a92e80so10483215ab.3 for ; Thu, 26 Jun 2025 03:05:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1750932334; x=1751537134; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=8SWlKXcbGfVq1bqP6GES795wTDd3bwzL3k0lB8D4I5A=; b=aa7oTcn8g02t+ORsxPgeJR7Fm3ahFA8w9RLARVGZEZzwf/00m5Oxo4M/ESeHvk1Uvu T1oNQLfO3czL3C0Xa8oeEMdlEx3yLEMkMZLMSBR1OENG305KY1Hv90vou8+taCCjleqz i5YJxozMvbgvgHe18ArlfCAGVsSlg+3BhJmhZapWN5cOws+x3eetOnc+uHvVKIIBYOPM 0nUCwjeYnqzY/5S+4c/pDC5hM0XetjyfjpiFMwoUVjzENnobIVM36lWmZtY9p33sCSDf rdmOPB8R7AVf8nmpG4RojLIE0EhFYpsgZO5mZ2P95/y8bnJ8OBQLW9yB6/rwW+HRa8Uw 9RBQ== X-Forwarded-Encrypted: i=1; AJvYcCWUMHzvDvZ/qVoPFbQXpQ+IjTlyk/8wiqNHxICMdvd1EP4KFVIOoODhR7+p0bnzwQcNJtE908ypz5kf6Q==@vger.kernel.org X-Gm-Message-State: AOJu0YzcOnhSZ2uMdyC/MvmQHpP7yOkqLgf3o7t4PA/9aWd9eypidDTC DuDCOotF7T7WBfuMh++uvtbywcIWHM+EcQEm0kOoQE4h1zn4cPc7su7xjG37VhRECAiQI7kvG+C ZBunPSpphVEhhetCNd+t+lfRJJ5d/0TPPQ0Am1L+GWFG7YZU25bkLKaDKsF0= X-Google-Smtp-Source: AGHT+IEC95MJBpOXmV0BZyyx3ets/sDykji5f1j958LFYCebNq95JTvE97nWMRpKRTGK1Us2OkmBPqvkw7VMiozqLd29WQLkIl41 Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:2703:b0:3dd:8663:d182 with SMTP id e9e14a558f8ab-3df329373fbmr58891975ab.13.1750932333860; Thu, 26 Jun 2025 03:05:33 -0700 (PDT) Date: Thu, 26 Jun 2025 03:05:33 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <685d1b6d.a00a0220.34b642.00fd.GAE@google.com> Subject: [syzbot] [btrfs?] possible deadlock in btrfs_join_transaction (2) From: syzbot To: clm@fb.com, dsterba@suse.com, josef@toxicpanda.com, linux-btrfs@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: 9aa9b43d689e Merge branch 'for-next/core' into for-kernelci git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci console output: https://syzkaller.appspot.com/x/log.txt?x=1796cdd4580000 kernel config: https://syzkaller.appspot.com/x/.config?x=27f179c74d5c35cd dashboard link: https://syzkaller.appspot.com/bug?extid=872fc61967352fcc3535 compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/974f3ac1c6a5/disk-9aa9b43d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/a5b5075d317f/vmlinux-9aa9b43d.xz kernel image: https://storage.googleapis.com/syzbot-assets/2f0ba7fec19b/Image-9aa9b43d.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+872fc61967352fcc3535@syzkaller.appspotmail.com ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 Not tainted ------------------------------------------------------ syz.2.224/7634 is trying to acquire lock: ffff0000c6b20618 (sb_internal#3){.+.+}-{0:0}, at: btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:830 but task is already holding lock: ffff0000d0c2b7d0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:374 [inline] ffff0000d0c2b7d0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x180/0x43c mm/util.c:577 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&mm->mmap_lock){++++}-{4:4}: down_read_killable+0x60/0x32c kernel/locking/rwsem.c:1547 mmap_read_lock_killable+0x28/0x8c include/linux/mmap_lock.h:421 get_mmap_lock_carefully mm/mmap_lock.c:197 [inline] lock_mm_and_find_vma+0x2a4/0x2d8 mm/mmap_lock.c:248 do_page_fault+0x51c/0x1554 arch/arm64/mm/fault.c:668 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:919 el1_abort+0x3c/0x5c arch/arm64/kernel/entry-common.c:455 el1h_64_sync_handler+0x50/0xcc arch/arm64/kernel/entry-common.c:533 el1h_64_sync+0x6c/0x70 arch/arm64/kernel/entry.S:595 __uaccess_mask_ptr arch/arm64/include/asm/uaccess.h:169 [inline] filldir64+0x2ec/0x6bc fs/readdir.c:379 dir_emit include/linux/fs.h:3917 [inline] kernfs_fop_readdir+0x498/0x79c fs/kernfs/dir.c:1910 iterate_dir+0x458/0x5e0 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64 fs/readdir.c:396 [inline] __arm64_sys_getdents64+0x110/0x2fc fs/readdir.c:396 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #4 (&root->kernfs_rwsem){++++}-{4:4}: down_write+0x50/0xc0 kernel/locking/rwsem.c:1577 kernfs_add_one+0x48/0x60c fs/kernfs/dir.c:791 kernfs_create_dir_ns+0xd4/0x12c fs/kernfs/dir.c:1093 sysfs_create_dir_ns+0x114/0x24c fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x5a8/0xb20 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_init_and_add+0x118/0x17c lib/kobject.c:457 btrfs_sysfs_add_qgroups+0x110/0x268 fs/btrfs/sysfs.c:2635 btrfs_quota_enable+0x224/0x1c70 fs/btrfs/qgroup.c:1030 btrfs_ioctl_quota_ctl+0x178/0x1bc fs/btrfs/ioctl.c:3673 btrfs_ioctl+0x86c/0xc3c fs/btrfs/ioctl.c:5323 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #3 (&fs_info->qgroup_ioctl_lock){+.+.}-{4:4}: __mutex_lock_common+0x1d0/0x2190 kernel/locking/mutex.c:602 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 btrfs_quota_enable+0x270/0x1c70 fs/btrfs/qgroup.c:1059 btrfs_ioctl_quota_ctl+0x178/0x1bc fs/btrfs/ioctl.c:3673 btrfs_ioctl+0x86c/0xc3c fs/btrfs/ioctl.c:5323 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c4 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}: join_transaction+0x190/0xb5c fs/btrfs/transaction.c:321 start_transaction+0x778/0x155c fs/btrfs/transaction.c:705 btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:830 __cow_file_range_inline+0x140/0xf14 fs/btrfs/inode.c:618 cow_file_range_inline+0x27c/0x338 fs/btrfs/inode.c:690 cow_file_range+0x324/0xc70 fs/btrfs/inode.c:1293 btrfs_run_delalloc_range+0x33c/0xd7c fs/btrfs/inode.c:2348 writepage_delalloc+0x8f0/0x103c fs/btrfs/extent_io.c:1386 extent_writepage fs/btrfs/extent_io.c:1717 [inline] extent_write_cache_pages fs/btrfs/extent_io.c:2403 [inline] btrfs_writepages+0x115c/0x20dc fs/btrfs/extent_io.c:2536 do_writepages+0x270/0x468 mm/page-writeback.c:2636 __writeback_single_inode+0x15c/0x13e8 fs/fs-writeback.c:1680 writeback_sb_inodes+0x558/0xe38 fs/fs-writeback.c:1976 wb_writeback+0x3cc/0xd70 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x338/0xdc0 fs/fs-writeback.c:2343 process_one_work+0x7e8/0x155c kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3402 kthread+0x5fc/0x75c kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847 -> #1 (btrfs_trans_num_writers){++++}-{0:0}: join_transaction+0x164/0xb5c fs/btrfs/transaction.c:320 start_transaction+0x778/0x155c fs/btrfs/transaction.c:705 btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:830 __cow_file_range_inline+0x140/0xf14 fs/btrfs/inode.c:618 cow_file_range_inline+0x27c/0x338 fs/btrfs/inode.c:690 cow_file_range+0x324/0xc70 fs/btrfs/inode.c:1293 btrfs_run_delalloc_range+0x33c/0xd7c fs/btrfs/inode.c:2348 writepage_delalloc+0x8f0/0x103c fs/btrfs/extent_io.c:1386 extent_writepage fs/btrfs/extent_io.c:1717 [inline] extent_write_cache_pages fs/btrfs/extent_io.c:2403 [inline] btrfs_writepages+0x115c/0x20dc fs/btrfs/extent_io.c:2536 do_writepages+0x270/0x468 mm/page-writeback.c:2636 __writeback_single_inode+0x15c/0x13e8 fs/fs-writeback.c:1680 writeback_sb_inodes+0x558/0xe38 fs/fs-writeback.c:1976 wb_writeback+0x3cc/0xd70 fs/fs-writeback.c:2156 wb_do_writeback fs/fs-writeback.c:2303 [inline] wb_workfn+0x338/0xdc0 fs/fs-writeback.c:2343 process_one_work+0x7e8/0x155c kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x958/0xed8 kernel/workqueue.c:3402 kthread+0x5fc/0x75c kernel/kthread.c:464 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847 -> #0 (sb_internal#3){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5240 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1793 [inline] sb_start_intwrite include/linux/fs.h:1976 [inline] start_transaction+0x5bc/0x155c fs/btrfs/transaction.c:699 btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:830 btrfs_dirty_inode+0x90/0x190 fs/btrfs/inode.c:6225 btrfs_update_time+0xa0/0xd0 fs/btrfs/inode.c:6259 inode_update_time fs/inode.c:2076 [inline] touch_atime+0x2e4/0x818 fs/inode.c:2149 file_accessed include/linux/fs.h:2650 [inline] btrfs_file_mmap+0xac/0x118 fs/btrfs/file.c:1988 call_mmap include/linux/fs.h:2284 [inline] mmap_file mm/internal.h:167 [inline] __mmap_new_file_vma mm/vma.c:2405 [inline] __mmap_new_vma mm/vma.c:2467 [inline] __mmap_region mm/vma.c:2622 [inline] mmap_region+0xe9c/0x1c0c mm/vma.c:2692 do_mmap+0x968/0xfac mm/mmap.c:561 vm_mmap_pgoff+0x2b8/0x43c mm/util.c:579 ksys_mmap_pgoff+0x394/0x5b8 mm/mmap.c:607 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline] __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline] __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 other info that might help us debug this: Chain exists of: sb_internal#3 --> &root->kernfs_rwsem --> &mm->mmap_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_lock); lock(&root->kernfs_rwsem); lock(&mm->mmap_lock); rlock(sb_internal#3); *** DEADLOCK *** 2 locks held by syz.2.224/7634: #0: ffff0000d0c2b7d0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:374 [inline] #0: ffff0000d0c2b7d0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x180/0x43c mm/util.c:577 #1: ffff0000c6b20428 (sb_writers#23){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2650 [inline] #1: ffff0000c6b20428 (sb_writers#23){.+.+}-{0:0}, at: btrfs_file_mmap+0xac/0x118 fs/btrfs/file.c:1988 stack backtrace: CPU: 1 UID: 0 PID: 7634 Comm: syz.2.224 Not tainted 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:501 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x324/0x32c kernel/locking/lockdep.c:2046 check_noncircular+0x154/0x174 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5240 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1793 [inline] sb_start_intwrite include/linux/fs.h:1976 [inline] start_transaction+0x5bc/0x155c fs/btrfs/transaction.c:699 btrfs_join_transaction+0x30/0x40 fs/btrfs/transaction.c:830 btrfs_dirty_inode+0x90/0x190 fs/btrfs/inode.c:6225 btrfs_update_time+0xa0/0xd0 fs/btrfs/inode.c:6259 inode_update_time fs/inode.c:2076 [inline] touch_atime+0x2e4/0x818 fs/inode.c:2149 file_accessed include/linux/fs.h:2650 [inline] btrfs_file_mmap+0xac/0x118 fs/btrfs/file.c:1988 call_mmap include/linux/fs.h:2284 [inline] mmap_file mm/internal.h:167 [inline] __mmap_new_file_vma mm/vma.c:2405 [inline] __mmap_new_vma mm/vma.c:2467 [inline] __mmap_region mm/vma.c:2622 [inline] mmap_region+0xe9c/0x1c0c mm/vma.c:2692 do_mmap+0x968/0xfac mm/mmap.c:561 vm_mmap_pgoff+0x2b8/0x43c mm/util.c:579 ksys_mmap_pgoff+0x394/0x5b8 mm/mmap.c:607 __do_sys_mmap arch/arm64/kernel/sys.c:28 [inline] __se_sys_mmap arch/arm64/kernel/sys.c:21 [inline] __arm64_sys_mmap+0xf8/0x110 arch/arm64/kernel/sys.c:21 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 --- 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