warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow ====================================================== WARNING: possible circular locking dependency detected 6.0.0-rc3-next-20220829 #1 Not tainted ------------------------------------------------------ syz-executor.5/4897 is trying to acquire lock: ffff88800c9c0400 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_bmap+0x4e/0x470 but task is already holding lock: ffff88800ffee3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x48b/0xc00 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&journal->j_checkpoint_mutex){+.+.}-{3:3}: mutex_lock_io_nested+0x148/0x1310 jbd2_journal_flush+0x19a/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #3 (&journal->j_barrier){+.+.}-{3:3}: __mutex_lock+0x136/0x14d0 jbd2_journal_lock_updates+0x15e/0x310 ext4_change_inode_journal_flag+0x17f/0x530 ext4_fileattr_set+0x140d/0x18a0 vfs_fileattr_set+0x77c/0xb80 do_vfs_ioctl+0xfc2/0x1610 __x64_sys_ioctl+0x10c/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&sbi->s_writepages_rwsem){++++}-{0:0}: ext4_writepages+0x1d2/0x3690 do_writepages+0x1b0/0x6a0 filemap_fdatawrite_wbc+0x147/0x1b0 __filemap_fdatawrite_range+0xb6/0x100 filemap_write_and_wait_range+0x89/0x110 __ext4_ioctl+0x1547/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (mapping.invalidate_lock){++++}-{3:3}: down_write+0x90/0x150 ext4_setattr+0x970/0x2b90 notify_change+0xcce/0x1420 do_truncate+0x13c/0x200 do_sys_ftruncate+0x3ec/0x730 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&sb->s_type->i_mutex_key#6){++++}-{3:3}: __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 down_read+0x98/0x450 ext4_bmap+0x4e/0x470 bmap+0xac/0x120 jbd2_journal_bmap+0xa8/0x180 jbd2_journal_flush+0x853/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#6 --> &journal->j_barrier --> &journal->j_checkpoint_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&journal->j_checkpoint_mutex); lock(&journal->j_barrier); lock(&journal->j_checkpoint_mutex); lock(&sb->s_type->i_mutex_key#6); *** DEADLOCK *** 2 locks held by syz-executor.5/4897: #0: ffff88800ffee170 (&journal->j_barrier){+.+.}-{3:3}, at: jbd2_journal_lock_updates+0x15e/0x310 #1: ffff88800ffee3f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: jbd2_journal_flush+0x48b/0xc00 stack backtrace: CPU: 0 PID: 4897 Comm: syz-executor.5 Not tainted 6.0.0-rc3-next-20220829 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x8b/0xb3 check_noncircular+0x263/0x2e0 __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 down_read+0x98/0x450 ext4_bmap+0x4e/0x470 bmap+0xac/0x120 jbd2_journal_bmap+0xa8/0x180 jbd2_journal_flush+0x853/0xc00 __ext4_ioctl+0x9e9/0x4090 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2721629b19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f271eb9f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f272173cf60 RCX: 00007f2721629b19 RDX: 0000000020000340 RSI: 000000004004662b RDI: 0000000000000007 RBP: 00007f2721683f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffda28097f R14: 00007f271eb9f300 R15: 0000000000022000 EXT4-fs warning (device loop0): ext4_multi_mount_protect:328: MMP startup interrupted, failing mount warning: checkpointing journal with EXT4_IOC_CHECKPOINT_FLAG_ZEROOUT can be slow EXT4-fs (loop7): unmounting filesystem. loop1: detected capacity change from 0 to 2048 loop0: detected capacity change from 0 to 2048 EXT4-fs (loop1): mounted filesystem without journal. Quota mode: writeback. EXT4-fs (loop1): unmounting filesystem. EXT4-fs warning (device loop0): ext4_multi_mount_protect:328: MMP startup interrupted, failing mount loop0: detected capacity change from 0 to 2048 loop7: detected capacity change from 0 to 2048 EXT4-fs (loop7): mounted filesystem without journal. Quota mode: none. ext4 filesystem being mounted at /syzkaller-testdir044950926/syzkaller.fxaZJd/45/file0 supports timestamps until 2038 (0x7fffffff) EXT4-fs (loop7): unmounting filesystem. EXT4-fs warning (device loop0): ext4_multi_mount_protect:328: MMP startup interrupted, failing mount loop5: detected capacity change from 0 to 5392 loop0: detected capacity change from 0 to 40 random: crng reseeded on system resumption random: crng reseeded on system resumption random: crng reseeded on system resumption syz-executor.0: attempt to access beyond end of device loop0: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop0, logical block 10, lost async page write loop0: detected capacity change from 0 to 40 loop6: detected capacity change from 0 to 40 random: crng reseeded on system resumption syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 10, lost async page write syz-executor.0: attempt to access beyond end of device loop0: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop0, logical block 10, lost async page write loop6: detected capacity change from 0 to 40 loop0: detected capacity change from 0 to 40 loop7: detected capacity change from 0 to 40 random: crng reseeded on system resumption syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 10, lost async page write syz-executor.0: attempt to access beyond end of device loop0: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop0, logical block 10, lost async page write syz-executor.7: attempt to access beyond end of device loop7: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop7, logical block 10, lost async page write loop0: detected capacity change from 0 to 40 loop6: detected capacity change from 0 to 40 syz-executor.0: attempt to access beyond end of device loop0: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop0, logical block 10, lost async page write syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 10, lost async page write loop7: detected capacity change from 0 to 40 syz-executor.7: attempt to access beyond end of device loop7: rw=2049, sector=40, nr_sectors = 4 limit=40 Buffer I/O error on dev loop7, logical block 10, lost async page write loop7: detected capacity change from 0 to 40