====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc7-next-20230206 #1 Not tainted ------------------------------------------------------ syz-executor.0/31913 is trying to acquire lock: ffff88800ff643f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x238/0x4b0 but task is already holding lock: ffff88801bfd4990 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_fallocate+0x2e1/0x3f50 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#6){++++}-{3:3}: down_read+0x3d/0x50 ext4_bmap+0x52/0x470 bmap+0xb0/0x130 jbd2_journal_bmap+0xac/0x1d0 jbd2_journal_flush+0x87f/0xc90 __ext4_ioctl+0x9fd/0x4330 __x64_sys_ioctl+0x19e/0x210 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc -> #0 (&journal->j_checkpoint_mutex){+.+.}-{3:3}: __lock_acquire+0x2da7/0x63b0 lock_acquire.part.0+0xec/0x320 mutex_lock_io_nested+0x149/0x1300 __jbd2_log_wait_for_space+0x238/0x4b0 add_transaction_credits+0xa42/0xb80 start_this_handle+0x3a6/0x14d0 jbd2__journal_start+0x394/0x6b0 __ext4_journal_start_sb+0x4c2/0x6f0 ext4_alloc_file_blocks.isra.0+0x2a2/0xbd0 ext4_fallocate+0x437/0x3f50 vfs_fallocate+0x48d/0xe30 __x64_sys_fallocate+0xd3/0x140 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#6); lock(&journal->j_checkpoint_mutex); lock(&sb->s_type->i_mutex_key#6); lock(&journal->j_checkpoint_mutex); *** DEADLOCK *** 2 locks held by syz-executor.0/31913: #0: ffff88800ff60438 (sb_writers#3){.+.+}-{0:0}, at: __x64_sys_fallocate+0xd3/0x140 #1: ffff88801bfd4990 (&sb->s_type->i_mutex_key#6){++++}-{3:3}, at: ext4_fallocate+0x2e1/0x3f50 stack backtrace: CPU: 0 PID: 31913 Comm: syz-executor.0 Not tainted 6.2.0-rc7-next-20230206 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0x91/0xf0 check_noncircular+0x263/0x2e0 __lock_acquire+0x2da7/0x63b0 lock_acquire.part.0+0xec/0x320 mutex_lock_io_nested+0x149/0x1300 __jbd2_log_wait_for_space+0x238/0x4b0 add_transaction_credits+0xa42/0xb80 start_this_handle+0x3a6/0x14d0 jbd2__journal_start+0x394/0x6b0 __ext4_journal_start_sb+0x4c2/0x6f0 ext4_alloc_file_blocks.isra.0+0x2a2/0xbd0 ext4_fallocate+0x437/0x3f50 vfs_fallocate+0x48d/0xe30 __x64_sys_fallocate+0xd3/0x140 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7face6975b19 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:00007face3eeb188 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007face6a88f60 RCX: 00007face6975b19 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007face69cff6d R08: 0000000000000000 R09: 0000000000000000 R10: 00000000087ffffc R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc27b96f8f R14: 00007face3eeb300 R15: 0000000000022000 audit: type=1400 audit(1675682253.199:62): avc: denied { tracepoint } for pid=32252 comm="syz-executor.0" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=perf_event permissive=1 EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted EXT4-fs warning (device sda): ext4_group_extend:1862: can't shrink FS - resize aborted