===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected 5.2.0+ #71 Not tainted ----------------------------------------------------- syz-executor.1/14753 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: 000000005abdaa18 (&fiq->waitq){+.+.}, at: spin_lock /./include/linux/spinlock.h:338 [inline] 000000005abdaa18 (&fiq->waitq){+.+.}, at: aio_poll /fs/aio.c:1751 [inline] 000000005abdaa18 (&fiq->waitq){+.+.}, at: __io_submit_one /fs/aio.c:1825 [inline] 000000005abdaa18 (&fiq->waitq){+.+.}, at: io_submit_one+0xe91/0x2de0 /fs/aio.c:1862 and this task is already holding: 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: spin_lock_irq /./include/linux/spinlock.h:363 [inline] 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: aio_poll /fs/aio.c:1749 [inline] 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: __io_submit_one /fs/aio.c:1825 [inline] 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: io_submit_one+0xe4c/0x2de0 /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+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock_irq /./include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x5d/0x80 /kernel/locking/spinlock.c:167 spin_lock_irq /./include/linux/spinlock.h:363 [inline] free_ioctx_users+0x2d/0x460 /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+0x49d/0x540 /lib/percpu-refcount.c:165 __rcu_reclaim /kernel/rcu/rcu.h:222 [inline] rcu_do_batch /kernel/rcu/tree.c:2114 [inline] rcu_core+0x66a/0x1470 /kernel/rcu/tree.c:2314 rcu_core_si+0x9/0x10 /kernel/rcu/tree.c:2323 __do_softirq+0x30d/0x970 /kernel/softirq.c:292 run_ksoftirqd /kernel/softirq.c:603 [inline] run_ksoftirqd+0x82/0x110 /kernel/softirq.c:595 smpboot_thread_fn+0x42d/0x8d0 /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+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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 cuse_send_init /fs/fuse/cuse.c:459 [inline] cuse_channel_open+0x5ba/0x830 /fs/fuse/cuse.c:519 misc_open+0x395/0x4c0 /drivers/char/misc.c:141 chrdev_open+0x245/0x6b0 /fs/char_dev.c:414 do_dentry_open+0x4df/0x1250 /fs/open.c:778 vfs_open+0xa0/0xd0 /fs/open.c:887 do_last /fs/namei.c:3416 [inline] path_openat+0x10e9/0x4630 /fs/namei.c:3533 do_filp_open+0x1a1/0x280 /fs/namei.c:3563 do_sys_open+0x3fe/0x5d0 /fs/open.c:1070 __do_sys_openat /fs/open.c:1097 [inline] __se_sys_openat /fs/open.c:1091 [inline] __x64_sys_openat+0x9d/0x100 /fs/open.c:1091 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 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.1/14753: #0: 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: spin_lock_irq /./include/linux/spinlock.h:363 [inline] #0: 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: aio_poll /fs/aio.c:1749 [inline] #0: 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: __io_submit_one /fs/aio.c:1825 [inline] #0: 0000000081456ec4 (&(&ctx->ctx_lock)->rlock){..-.}, at: io_submit_one+0xe4c/0x2de0 /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+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock_irq /./include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x5d/0x80 /kernel/locking/spinlock.c:167 spin_lock_irq /./include/linux/spinlock.h:363 [inline] free_ioctx_users+0x2d/0x460 /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+0x49d/0x540 /lib/percpu-refcount.c:165 __rcu_reclaim /kernel/rcu/rcu.h:222 [inline] rcu_do_batch /kernel/rcu/tree.c:2114 [inline] rcu_core+0x66a/0x1470 /kernel/rcu/tree.c:2314 rcu_core_si+0x9/0x10 /kernel/rcu/tree.c:2323 __do_softirq+0x30d/0x970 /kernel/softirq.c:292 run_ksoftirqd /kernel/softirq.c:603 [inline] run_ksoftirqd+0x82/0x110 /kernel/softirq.c:595 smpboot_thread_fn+0x42d/0x8d0 /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+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock_irq /./include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0x5d/0x80 /kernel/locking/spinlock.c:167 spin_lock_irq /./include/linux/spinlock.h:363 [inline] aio_poll /fs/aio.c:1749 [inline] __io_submit_one /fs/aio.c:1825 [inline] io_submit_one+0xe4c/0x2de0 /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/0x540 /fs/aio.c:1891 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe } ... key at: [] __key.53923+0x0/0x40 ... acquired at: lock_acquire+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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+0xe91/0x2de0 /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/0x540 /fs/aio.c:1891 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 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+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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 cuse_send_init /fs/fuse/cuse.c:459 [inline] cuse_channel_open+0x5ba/0x830 /fs/fuse/cuse.c:519 misc_open+0x395/0x4c0 /drivers/char/misc.c:141 chrdev_open+0x245/0x6b0 /fs/char_dev.c:414 do_dentry_open+0x4df/0x1250 /fs/open.c:778 vfs_open+0xa0/0xd0 /fs/open.c:887 do_last /fs/namei.c:3416 [inline] path_openat+0x10e9/0x4630 /fs/namei.c:3533 do_filp_open+0x1a1/0x280 /fs/namei.c:3563 do_sys_open+0x3fe/0x5d0 /fs/open.c:1070 __do_sys_openat /fs/open.c:1097 [inline] __se_sys_openat /fs/open.c:1091 [inline] __x64_sys_openat+0x9d/0x100 /fs/open.c:1091 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe SOFTIRQ-ON-W at: lock_acquire+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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 cuse_send_init /fs/fuse/cuse.c:459 [inline] cuse_channel_open+0x5ba/0x830 /fs/fuse/cuse.c:519 misc_open+0x395/0x4c0 /drivers/char/misc.c:141 chrdev_open+0x245/0x6b0 /fs/char_dev.c:414 do_dentry_open+0x4df/0x1250 /fs/open.c:778 vfs_open+0xa0/0xd0 /fs/open.c:887 do_last /fs/namei.c:3416 [inline] path_openat+0x10e9/0x4630 /fs/namei.c:3533 do_filp_open+0x1a1/0x280 /fs/namei.c:3563 do_sys_open+0x3fe/0x5d0 /fs/open.c:1070 __do_sys_openat /fs/open.c:1097 [inline] __se_sys_openat /fs/open.c:1091 [inline] __x64_sys_openat+0x9d/0x100 /fs/open.c:1091 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe INITIAL USE at: lock_acquire+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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 cuse_send_init /fs/fuse/cuse.c:459 [inline] cuse_channel_open+0x5ba/0x830 /fs/fuse/cuse.c:519 misc_open+0x395/0x4c0 /drivers/char/misc.c:141 chrdev_open+0x245/0x6b0 /fs/char_dev.c:414 do_dentry_open+0x4df/0x1250 /fs/open.c:778 vfs_open+0xa0/0xd0 /fs/open.c:887 do_last /fs/namei.c:3416 [inline] path_openat+0x10e9/0x4630 /fs/namei.c:3533 do_filp_open+0x1a1/0x280 /fs/namei.c:3563 do_sys_open+0x3fe/0x5d0 /fs/open.c:1070 __do_sys_openat /fs/open.c:1097 [inline] __se_sys_openat /fs/open.c:1091 [inline] __x64_sys_openat+0x9d/0x100 /fs/open.c:1091 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe } ... key at: [] __key.44293+0x0/0x40 ... acquired at: lock_acquire+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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+0xe91/0x2de0 /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/0x540 /fs/aio.c:1891 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe stack backtrace: CPU: 0 PID: 14753 Comm: syz-executor.1 Not tainted 5.2.0+ #71 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+0x16f/0x1f0 /lib/dump_stack.c:113 print_bad_irq_dependency /kernel/locking/lockdep.c:2025 [inline] check_irq_usage.cold+0x5b4/0x72e /kernel/locking/lockdep.c:2223 check_prev_add /kernel/locking/lockdep.c:2409 [inline] check_prevs_add /kernel/locking/lockdep.c:2507 [inline] validate_chain /kernel/locking/lockdep.c:2897 [inline] __lock_acquire+0x25c3/0x4c30 /kernel/locking/lockdep.c:3880 lock_acquire+0x190/0x400 /kernel/locking/lockdep.c:4413 __raw_spin_lock /./include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2b/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+0xe91/0x2de0 /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/0x540 /fs/aio.c:1891 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 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:00007fb8396c4c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459819 RDX: 0000000020000200 RSI: 0000000000000001 RDI: 00007fb8396a4000 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb8396c56d4 R13: 00000000004c0c01 R14: 00000000004d39e8 R15: 00000000ffffffff