======================================================== WARNING: possible irq lock inversion dependency detected 5.3.0-rc4-next-20190816 #67 Not tainted -------------------------------------------------------- udevd/3894 just changed the state of lock: ffff888097a05b58 (&(&ctx->ctx_lock)->rlock){..-.}, at: spin_lock_irq include/linux/spinlock.h:363 [inline] ffff888097a05b58 (&(&ctx->ctx_lock)->rlock){..-.}, at: free_ioctx_users+0x2d/0x490 fs/aio.c:618 but this lock took another, SOFTIRQ-unsafe lock in the past: (&fiq->waitq){+.+.} and interrupts could create inverse lock ordering between them. 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 *** 3 locks held by udevd/3894: #0: ffffffff88fa9a80 (rcu_read_lock){....}, at: file_ctx security/apparmor/include/file.h:33 [inline] #0: ffffffff88fa9a80 (rcu_read_lock){....}, at: aa_file_perm+0x125/0xdd0 security/apparmor/file.c:617 #1: ffffffff88fa99c0 (rcu_callback){....}, at: __rcu_reclaim kernel/rcu/rcu.h:210 [inline] #1: ffffffff88fa99c0 (rcu_callback){....}, at: rcu_do_batch kernel/rcu/tree.c:2157 [inline] #1: ffffffff88fa99c0 (rcu_callback){....}, at: rcu_core+0x60e/0x1560 kernel/rcu/tree.c:2377 #2: ffffffff88fa9a00 (rcu_read_lock_sched){....}, at: percpu_ref_call_confirm_rcu lib/percpu-refcount.c:126 [inline] #2: ffffffff88fa9a00 (rcu_read_lock_sched){....}, at: percpu_ref_switch_to_atomic_rcu+0x20e/0x570 lib/percpu-refcount.c:165 the shortest dependencies between 2nd lock and 1st 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 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:797 vfs_open+0xa0/0xd0 fs/open.c:914 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:1097 __do_sys_openat fs/open.c:1124 [inline] __se_sys_openat fs/open.c:1118 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1118 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 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:797 vfs_open+0xa0/0xd0 fs/open.c:914 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:1097 __do_sys_openat fs/open.c:1124 [inline] __se_sys_openat fs/open.c:1118 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1118 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 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:797 vfs_open+0xa0/0xd0 fs/open.c:914 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:1097 __do_sys_openat fs/open.c:1124 [inline] __se_sys_openat fs/open.c:1118 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1118 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe } ... key at: [] __key.45688+0x0/0x40 ... acquired at: __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:1748 [inline] __io_submit_one fs/aio.c:1822 [inline] io_submit_one+0xefa/0x2ef0 fs/aio.c:1859 __do_sys_io_submit fs/aio.c:1918 [inline] __se_sys_io_submit fs/aio.c:1888 [inline] __x64_sys_io_submit+0x1bd/0x570 fs/aio.c:1888 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> (&(&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 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 rcu_is_watching+0x1/0x30 kernel/rcu/tree.c:897 common_file_perm+0x167/0x720 security/apparmor/lsm.c:461 apparmor_file_permission+0x25/0x30 security/apparmor/lsm.c:474 security_file_permission+0x79/0x380 security/security.c:1375 rw_verify_area+0x11e/0x360 fs/read_write.c:399 vfs_write+0x149/0x5d0 fs/read_write.c:553 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 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_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] __do_sys_io_cancel fs/aio.c:2000 [inline] __se_sys_io_cancel fs/aio.c:1982 [inline] __x64_sys_io_cancel+0xd4/0x690 fs/aio.c:1982 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe } ... key at: [] __key.54219+0x0/0x40 ... acquired at: mark_lock_irq kernel/locking/lockdep.c:3317 [inline] mark_lock+0x517/0x1220 kernel/locking/lockdep.c:3666 mark_usage kernel/locking/lockdep.c:3566 [inline] __lock_acquire+0x1eaf/0x4e70 kernel/locking/lockdep.c:3909 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 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 rcu_is_watching+0x1/0x30 kernel/rcu/tree.c:897 common_file_perm+0x167/0x720 security/apparmor/lsm.c:461 apparmor_file_permission+0x25/0x30 security/apparmor/lsm.c:474 security_file_permission+0x79/0x380 security/security.c:1375 rw_verify_area+0x11e/0x360 fs/read_write.c:399 vfs_write+0x149/0x5d0 fs/read_write.c:553 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe stack backtrace: CPU: 1 PID: 3894 Comm: udevd Not tainted 5.3.0-rc4-next-20190816 #67 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_irq_inversion_bug.part.0+0x2e4/0x2f1 kernel/locking/lockdep.c:3179 print_irq_inversion_bug kernel/locking/lockdep.c:3180 [inline] check_usage_forwards.cold+0x20/0x29 kernel/locking/lockdep.c:3204 mark_lock_irq kernel/locking/lockdep.c:3317 [inline] mark_lock+0x517/0x1220 kernel/locking/lockdep.c:3666 mark_usage kernel/locking/lockdep.c:3566 [inline] __lock_acquire+0x1eaf/0x4e70 kernel/locking/lockdep.c:3909 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 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:rcu_is_watching+0x1/0x30 kernel/rcu/tree.c:897 Code: 5d d1 e8 83 f0 01 83 e0 01 c3 4c 89 e7 e8 67 41 4d 00 eb df 48 89 45 e8 e8 7c 41 4d 00 48 8b 45 e8 eb 8e 66 0f 1f 44 00 00 55 <48> 89 e5 65 ff 05 fd 31 a2 7e e8 40 ff ff ff 83 f0 01 65 ff 0d ee RSP: 0018:ffff8880966b7b80 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffff8880966a80c0 RBX: 0000000000000000 RCX: ffffffff830d6044 RDX: 0000000000000000 RSI: ffffffff830d6051 RDI: 0000000000000001 RBP: ffff8880966b7ce8 R08: ffff8880966a80c0 R09: ffffed1015d26ad5 R10: ffffed1015d26ad4 R11: ffff8880ae9356a3 R12: ffff88821bc92bb0 R13: ffff88808f1fcbc8 R14: ffff88821bc92bb0 R15: 0000000000000000 common_file_perm+0x167/0x720 security/apparmor/lsm.c:461 apparmor_file_permission+0x25/0x30 security/apparmor/lsm.c:474 security_file_permission+0x79/0x380 security/security.c:1375 rw_verify_area+0x11e/0x360 fs/read_write.c:399 vfs_write+0x149/0x5d0 fs/read_write.c:553 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f9b4c832370 Code: 73 01 c3 48 8b 0d c8 4a 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d 85 a2 2b 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 0e 8a 01 00 48 89 04 24 RSP: 002b:00007fffbe796318 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000000000a RCX: 00007f9b4c832370 RDX: 000000000000000a RSI: 00007f9b4d131000 RDI: 0000000000000005 RBP: 00007f9b4d131000 R08: 00007f9b4d12a7a0 R09: 00000000ffffffff R10: 0000000000000040 R11: 0000000000000246 R12: 00000000021a2680 R13: 000000000000000a R14: 0000000000000000 R15: 000000000000000a