Warning: Permanently added '10.128.10.4' (ED25519) to the list of known hosts. executing program [ 74.764011][ T5823] [ 74.766391][ T5823] ====================================================== [ 74.773408][ T5823] WARNING: possible circular locking dependency detected [ 74.780425][ T5823] 6.14.0-syzkaller-05877-g1a9239bb4253 #0 Not tainted [ 74.787183][ T5823] ------------------------------------------------------ [ 74.794189][ T5823] syz-executor192/5823 is trying to acquire lock: [ 74.800611][ T5823] ffff888144302cd8 (&q->elevator_lock){+.+.}-{4:4}, at: elv_iosched_store+0x201/0x5f0 [ 74.810249][ T5823] [ 74.810249][ T5823] but task is already holding lock: [ 74.817624][ T5823] ffff8881443027a8 (&q->q_usage_counter(io)#58){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 [ 74.828890][ T5823] [ 74.828890][ T5823] which lock already depends on the new lock. [ 74.828890][ T5823] [ 74.839295][ T5823] [ 74.839295][ T5823] the existing dependency chain (in reverse order) is: [ 74.848309][ T5823] [ 74.848309][ T5823] -> #2 (&q->q_usage_counter(io)#58){++++}-{0:0}: [ 74.856947][ T5823] blk_alloc_queue+0x619/0x760 [ 74.862250][ T5823] blk_mq_alloc_queue+0x179/0x290 [ 74.867813][ T5823] __blk_mq_alloc_disk+0x29/0x120 [ 74.873385][ T5823] nbd_dev_add+0x49d/0xbb0 [ 74.878347][ T5823] nbd_init+0x181/0x320 [ 74.883054][ T5823] do_one_initcall+0x120/0x6e0 [ 74.888363][ T5823] kernel_init_freeable+0x5c2/0x900 [ 74.894111][ T5823] kernel_init+0x1c/0x2b0 [ 74.898982][ T5823] ret_from_fork+0x45/0x80 [ 74.903944][ T5823] ret_from_fork_asm+0x1a/0x30 [ 74.909252][ T5823] [ 74.909252][ T5823] -> #1 (fs_reclaim){+.+.}-{0:0}: [ 74.916486][ T5823] fs_reclaim_acquire+0x102/0x150 [ 74.922051][ T5823] blk_mq_alloc_and_init_hctx+0x503/0x11c0 [ 74.928394][ T5823] blk_mq_realloc_hw_ctxs+0x8f6/0xc00 [ 74.934313][ T5823] blk_mq_init_allocated_queue+0x3af/0x1230 [ 74.940766][ T5823] blk_mq_alloc_queue+0x1c2/0x290 [ 74.946341][ T5823] __blk_mq_alloc_disk+0x29/0x120 [ 74.951910][ T5823] loop_add+0x496/0xb70 [ 74.956600][ T5823] loop_init+0x164/0x270 [ 74.961377][ T5823] do_one_initcall+0x120/0x6e0 [ 74.966703][ T5823] kernel_init_freeable+0x5c2/0x900 [ 74.972441][ T5823] kernel_init+0x1c/0x2b0 [ 74.977303][ T5823] ret_from_fork+0x45/0x80 [ 74.982249][ T5823] ret_from_fork_asm+0x1a/0x30 [ 74.987558][ T5823] [ 74.987558][ T5823] -> #0 (&q->elevator_lock){+.+.}-{4:4}: [ 74.995400][ T5823] __lock_acquire+0x1173/0x1ba0 [ 75.000788][ T5823] lock_acquire+0x179/0x350 [ 75.005845][ T5823] __mutex_lock+0x19a/0xb00 [ 75.010886][ T5823] elv_iosched_store+0x201/0x5f0 [ 75.016365][ T5823] queue_attr_store+0x270/0x310 [ 75.021756][ T5823] sysfs_kf_write+0x117/0x170 [ 75.026968][ T5823] kernfs_fop_write_iter+0x349/0x510 [ 75.032785][ T5823] iter_file_splice_write+0x91c/0x1150 [ 75.038807][ T5823] direct_splice_actor+0x18f/0x6c0 [ 75.044452][ T5823] splice_direct_to_actor+0x342/0xa30 [ 75.050361][ T5823] do_splice_direct+0x174/0x240 [ 75.055751][ T5823] do_sendfile+0xafd/0xe50 [ 75.060708][ T5823] __x64_sys_sendfile64+0x1d8/0x220 [ 75.066455][ T5823] do_syscall_64+0xcd/0x260 [ 75.071513][ T5823] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 75.077956][ T5823] [ 75.077956][ T5823] other info that might help us debug this: [ 75.077956][ T5823] [ 75.088198][ T5823] Chain exists of: [ 75.088198][ T5823] &q->elevator_lock --> fs_reclaim --> &q->q_usage_counter(io)#58 [ 75.088198][ T5823] [ 75.101975][ T5823] Possible unsafe locking scenario: [ 75.101975][ T5823] [ 75.109516][ T5823] CPU0 CPU1 [ 75.114889][ T5823] ---- ---- [ 75.120260][ T5823] lock(&q->q_usage_counter(io)#58); [ 75.125664][ T5823] lock(fs_reclaim); [ 75.132194][ T5823] lock(&q->q_usage_counter(io)#58); [ 75.140134][ T5823] lock(&q->elevator_lock); [ 75.144746][ T5823] [ 75.144746][ T5823] *** DEADLOCK *** [ 75.144746][ T5823] [ 75.152897][ T5823] 5 locks held by syz-executor192/5823: [ 75.158446][ T5823] #0: ffff888035bd2420 (sb_writers#7){.+.+}-{0:0}, at: splice_direct_to_actor+0x342/0xa30 [ 75.168507][ T5823] #1: ffff888033e17088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x287/0x510 [ 75.178293][ T5823] #2: ffff8880258933c8 (kn->active#47){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2aa/0x510 [ 75.188360][ T5823] #3: ffff8881443027a8 (&q->q_usage_counter(io)#58){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 [ 75.200170][ T5823] #4: ffff8881443027e0 (&q->q_usage_counter(queue)#10){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 [ 75.212142][ T5823] [ 75.212142][ T5823] stack backtrace: [ 75.218044][ T5823] CPU: 0 UID: 0 PID: 5823 Comm: syz-executor192 Not tainted 6.14.0-syzkaller-05877-g1a9239bb4253 #0 PREEMPT(full) [ 75.218073][ T5823] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 [ 75.218090][ T5823] Call Trace: [ 75.218099][ T5823] [ 75.218111][ T5823] dump_stack_lvl+0x116/0x1f0 [ 75.218138][ T5823] print_circular_bug+0x275/0x350 [ 75.218169][ T5823] check_noncircular+0x14c/0x170 [ 75.218200][ T5823] __lock_acquire+0x1173/0x1ba0 [ 75.218233][ T5823] ? __lock_acquire+0xaa4/0x1ba0 [ 75.218264][ T5823] lock_acquire+0x179/0x350 [ 75.218293][ T5823] ? elv_iosched_store+0x201/0x5f0 [ 75.218323][ T5823] ? __pfx___might_resched+0x10/0x10 [ 75.218358][ T5823] __mutex_lock+0x19a/0xb00 [ 75.218378][ T5823] ? elv_iosched_store+0x201/0x5f0 [ 75.218407][ T5823] ? mark_held_locks+0x49/0x80 [ 75.218436][ T5823] ? elv_iosched_store+0x201/0x5f0 [ 75.218464][ T5823] ? lockdep_hardirqs_on+0x7c/0x110 [ 75.218500][ T5823] ? __pfx___mutex_lock+0x10/0x10 [ 75.218522][ T5823] ? blk_mq_freeze_queue_wait+0xad/0x1b0 [ 75.218557][ T5823] ? __pfx_autoremove_wake_function+0x10/0x10 [ 75.218589][ T5823] ? elv_iosched_store+0x201/0x5f0 [ 75.218618][ T5823] elv_iosched_store+0x201/0x5f0 [ 75.218646][ T5823] ? do_syscall_64+0xcd/0x260 [ 75.218667][ T5823] ? __pfx_elv_iosched_store+0x10/0x10 [ 75.218697][ T5823] ? __mutex_trylock_common+0xe9/0x250 [ 75.218729][ T5823] ? __pfx_elv_iosched_store+0x10/0x10 [ 75.218758][ T5823] queue_attr_store+0x270/0x310 [ 75.218794][ T5823] ? __pfx_queue_attr_store+0x10/0x10 [ 75.218829][ T5823] ? __lock_acquire+0x5ca/0x1ba0 [ 75.218860][ T5823] ? kernfs_fop_write_iter+0x287/0x510 [ 75.218892][ T5823] ? __pfx_queue_attr_store+0x10/0x10 [ 75.218928][ T5823] sysfs_kf_write+0x117/0x170 [ 75.218956][ T5823] kernfs_fop_write_iter+0x349/0x510 [ 75.219000][ T5823] ? __pfx_sysfs_kf_write+0x10/0x10 [ 75.219031][ T5823] iter_file_splice_write+0x91c/0x1150 [ 75.219074][ T5823] ? __pfx_iter_file_splice_write+0x10/0x10 [ 75.219111][ T5823] ? __pfx_copy_splice_read+0x10/0x10 [ 75.219149][ T5823] ? __pfx_iter_file_splice_write+0x10/0x10 [ 75.219184][ T5823] direct_splice_actor+0x18f/0x6c0 [ 75.219219][ T5823] splice_direct_to_actor+0x342/0xa30 [ 75.219253][ T5823] ? __pfx_direct_splice_actor+0x10/0x10 [ 75.219288][ T5823] ? __pfx_splice_direct_to_actor+0x10/0x10 [ 75.219325][ T5823] do_splice_direct+0x174/0x240 [ 75.219364][ T5823] ? __pfx_do_splice_direct+0x10/0x10 [ 75.219396][ T5823] ? __pfx_direct_file_splice_eof+0x10/0x10 [ 75.219430][ T5823] ? rw_verify_area+0xcf/0x680 [ 75.219460][ T5823] do_sendfile+0xafd/0xe50 [ 75.219491][ T5823] ? __pfx_do_sendfile+0x10/0x10 [ 75.219526][ T5823] __x64_sys_sendfile64+0x1d8/0x220 [ 75.219548][ T5823] ? __pfx___x64_sys_sendfile64+0x10/0x10 [ 75.219574][ T5823] do_syscall_64+0xcd/0x260 [ 75.219603][ T5823] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 75.219646][ T5823] RIP: 0033:0x7ff2c3abb2e9 [ 75.219670][ T5823] Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 [ 75.219698][ T5823] RSP: 002b:00007fffc4e88b88 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 [ 75.219721][ T5823] RAX: ffffffffffffffda RBX: 00007fffc4e88d58 RCX: 00007ff2c3abb2e9 [ 75.219737][ T5823] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003 [ 75.219752][ T5823] RBP: 00007ff2c3b2e610 R08: 0000000000000000 R09: 00007fffc4e88d58 [ 75.219768][ T5823] R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000001 [ 75.219783][ T5823] R13: 00007fffc4e88d48 R14: 0000000000000001 R15: 0000