===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 5.3.0+ #0 Not tainted ----------------------------------------------------- syz-executor.0/14749 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: ffff888095a752a8 (&fiq->waitq){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline] ffff888095a752a8 (&fiq->waitq){+.+.}, at: aio_poll fs/aio.c:1751 [inline] ffff888095a752a8 (&fiq->waitq){+.+.}, at: __io_submit_one fs/aio.c:1825 [inline] ffff888095a752a8 (&fiq->waitq){+.+.}, at: io_submit_one+0xefa/0x2ef0 fs/aio.c:1862 and this task is already holding: ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: spin_lock_irq include/linux/spinlock.h:363 [inline] ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: aio_poll fs/aio.c:1749 [inline] ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: __io_submit_one fs/aio.c:1825 [inline] ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: io_submit_one+0xeb5/0x2ef0 fs/aio.c:1862 which would create a new lock dependency: (&(&ctx->ctx_lock)->rlock){..-.} -> (&fiq->waitq){+.+.} but this new dependency connects a SOFTIRQ-irq-safe lock: (&(&ctx->ctx_lock)->rlock){..-.} ... which became SOFTIRQ-irq-safe at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x60/0x80 kernel/locking/spinlock.c:167 spin_lock_irq include/linux/spinlock.h:363 [inline] free_ioctx_users+0x2d/0x490 fs/aio.c:618 percpu_ref_put_many include/linux/percpu-refcount.h:293 [inline] percpu_ref_put include/linux/percpu-refcount.h:309 [inline] percpu_ref_call_confirm_rcu lib/percpu-refcount.c:130 [inline] percpu_ref_switch_to_atomic_rcu+0x4c0/0x570 lib/percpu-refcount.c:165 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2157 [inline] rcu_core+0x581/0x1560 kernel/rcu/tree.c:2377 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2386 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 to a SOFTIRQ-irq-unsafe lock: (&fiq->waitq){+.+.} ... which became SOFTIRQ-irq-unsafe at: ... lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] flush_bg_queue+0x1f3/0x3c0 fs/fuse/dev.c:415 fuse_request_queue_background+0x2f8/0x5a0 fs/fuse/dev.c:676 fuse_request_send_background+0x58/0x110 fs/fuse/dev.c:687 fuse_send_init fs/fuse/inode.c:986 [inline] fuse_fill_super+0x13cd/0x1730 fs/fuse/inode.c:1211 mount_nodev+0x66/0x110 fs/super.c:1458 fuse_mount+0x2d/0x40 fs/fuse/inode.c:1236 legacy_get_tree+0x108/0x220 fs/fs_context.c:659 vfs_get_tree+0x8e/0x390 fs/super.c:1542 do_new_mount fs/namespace.c:2825 [inline] do_mount+0x1453/0x1d80 fs/namespace.c:3145 ksys_mount+0xdb/0x150 fs/namespace.c:3354 __do_sys_mount fs/namespace.c:3368 [inline] __se_sys_mount fs/namespace.c:3365 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3365 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fiq->waitq); local_irq_disable(); lock(&(&ctx->ctx_lock)->rlock); lock(&fiq->waitq); lock(&(&ctx->ctx_lock)->rlock); *** DEADLOCK *** 1 lock held by syz-executor.0/14749: #0: ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: spin_lock_irq include/linux/spinlock.h:363 [inline] #0: ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: aio_poll fs/aio.c:1749 [inline] #0: ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: __io_submit_one fs/aio.c:1825 [inline] #0: ffff88808bd59d18 (&(&ctx->ctx_lock)->rlock){..-.}, at: io_submit_one+0xeb5/0x2ef0 fs/aio.c:1862 the dependencies between SOFTIRQ-irq-safe lock and the holding lock: -> (&(&ctx->ctx_lock)->rlock){..-.} { IN-SOFTIRQ-W at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x60/0x80 kernel/locking/spinlock.c:167 spin_lock_irq include/linux/spinlock.h:363 [inline] free_ioctx_users+0x2d/0x490 fs/aio.c:618 percpu_ref_put_many include/linux/percpu-refcount.h:293 [inline] percpu_ref_put include/linux/percpu-refcount.h:309 [inline] percpu_ref_call_confirm_rcu lib/percpu-refcount.c:130 [inline] percpu_ref_switch_to_atomic_rcu+0x4c0/0x570 lib/percpu-refcount.c:165 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2157 [inline] rcu_core+0x581/0x1560 kernel/rcu/tree.c:2377 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2386 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 INITIAL USE at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x60/0x80 kernel/locking/spinlock.c:167 spin_lock_irq include/linux/spinlock.h:363 [inline] free_ioctx_users+0x2d/0x490 fs/aio.c:618 percpu_ref_put_many include/linux/percpu-refcount.h:293 [inline] percpu_ref_put include/linux/percpu-refcount.h:309 [inline] percpu_ref_call_confirm_rcu lib/percpu-refcount.c:130 [inline] percpu_ref_switch_to_atomic_rcu+0x4c0/0x570 lib/percpu-refcount.c:165 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2157 [inline] rcu_core+0x581/0x1560 kernel/rcu/tree.c:2377 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2386 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 } ... key at: [] __key.54293+0x0/0x40 ... acquired at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] aio_poll fs/aio.c:1751 [inline] __io_submit_one fs/aio.c:1825 [inline] io_submit_one+0xefa/0x2ef0 fs/aio.c:1862 __do_sys_io_submit fs/aio.c:1921 [inline] __se_sys_io_submit fs/aio.c:1891 [inline] __x64_sys_io_submit+0x1bd/0x570 fs/aio.c:1891 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe the dependencies between the lock to be acquired and SOFTIRQ-irq-unsafe lock: -> (&fiq->waitq){+.+.} { HARDIRQ-ON-W at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] flush_bg_queue+0x1f3/0x3c0 fs/fuse/dev.c:415 fuse_request_queue_background+0x2f8/0x5a0 fs/fuse/dev.c:676 fuse_request_send_background+0x58/0x110 fs/fuse/dev.c:687 fuse_send_init fs/fuse/inode.c:986 [inline] fuse_fill_super+0x13cd/0x1730 fs/fuse/inode.c:1211 mount_nodev+0x66/0x110 fs/super.c:1458 fuse_mount+0x2d/0x40 fs/fuse/inode.c:1236 legacy_get_tree+0x108/0x220 fs/fs_context.c:659 vfs_get_tree+0x8e/0x390 fs/super.c:1542 do_new_mount fs/namespace.c:2825 [inline] do_mount+0x1453/0x1d80 fs/namespace.c:3145 ksys_mount+0xdb/0x150 fs/namespace.c:3354 __do_sys_mount fs/namespace.c:3368 [inline] __se_sys_mount fs/namespace.c:3365 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3365 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe SOFTIRQ-ON-W at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] flush_bg_queue+0x1f3/0x3c0 fs/fuse/dev.c:415 fuse_request_queue_background+0x2f8/0x5a0 fs/fuse/dev.c:676 fuse_request_send_background+0x58/0x110 fs/fuse/dev.c:687 fuse_send_init fs/fuse/inode.c:986 [inline] fuse_fill_super+0x13cd/0x1730 fs/fuse/inode.c:1211 mount_nodev+0x66/0x110 fs/super.c:1458 fuse_mount+0x2d/0x40 fs/fuse/inode.c:1236 legacy_get_tree+0x108/0x220 fs/fs_context.c:659 vfs_get_tree+0x8e/0x390 fs/super.c:1542 do_new_mount fs/namespace.c:2825 [inline] do_mount+0x1453/0x1d80 fs/namespace.c:3145 ksys_mount+0xdb/0x150 fs/namespace.c:3354 __do_sys_mount fs/namespace.c:3368 [inline] __se_sys_mount fs/namespace.c:3365 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3365 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe INITIAL USE at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] flush_bg_queue+0x1f3/0x3c0 fs/fuse/dev.c:415 fuse_request_queue_background+0x2f8/0x5a0 fs/fuse/dev.c:676 fuse_request_send_background+0x58/0x110 fs/fuse/dev.c:687 fuse_send_init fs/fuse/inode.c:986 [inline] fuse_fill_super+0x13cd/0x1730 fs/fuse/inode.c:1211 mount_nodev+0x66/0x110 fs/super.c:1458 fuse_mount+0x2d/0x40 fs/fuse/inode.c:1236 legacy_get_tree+0x108/0x220 fs/fs_context.c:659 vfs_get_tree+0x8e/0x390 fs/super.c:1542 do_new_mount fs/namespace.c:2825 [inline] do_mount+0x1453/0x1d80 fs/namespace.c:3145 ksys_mount+0xdb/0x150 fs/namespace.c:3354 __do_sys_mount fs/namespace.c:3368 [inline] __se_sys_mount fs/namespace.c:3365 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3365 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe } ... key at: [] __key.44672+0x0/0x40 ... acquired at: lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] aio_poll fs/aio.c:1751 [inline] __io_submit_one fs/aio.c:1825 [inline] io_submit_one+0xefa/0x2ef0 fs/aio.c:1862 __do_sys_io_submit fs/aio.c:1921 [inline] __se_sys_io_submit fs/aio.c:1891 [inline] __x64_sys_io_submit+0x1bd/0x570 fs/aio.c:1891 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe stack backtrace: CPU: 0 PID: 14749 Comm: syz-executor.0 Not tainted 5.3.0+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_bad_irq_dependency kernel/locking/lockdep.c:2095 [inline] check_irq_usage.cold+0x586/0x6fe kernel/locking/lockdep.c:2293 check_prev_add kernel/locking/lockdep.c:2480 [inline] check_prevs_add kernel/locking/lockdep.c:2581 [inline] validate_chain kernel/locking/lockdep.c:2971 [inline] __lock_acquire+0x25d0/0x4e70 kernel/locking/lockdep.c:3955 lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:338 [inline] aio_poll fs/aio.c:1751 [inline] __io_submit_one fs/aio.c:1825 [inline] io_submit_one+0xefa/0x2ef0 fs/aio.c:1862 __do_sys_io_submit fs/aio.c:1921 [inline] __se_sys_io_submit fs/aio.c:1891 [inline] __x64_sys_io_submit+0x1bd/0x570 fs/aio.c:1891 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a09 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8aef0cec78 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a09 RDX: 0000000020002600 RSI: 0000000000000002 RDI: 00007f8aef0ae000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8aef0cf6d4 R13: 00000000004c0dea R14: 00000000004d3f98 R15: 00000000ffffffff