====================================================== WARNING: possible circular locking dependency detected 6.1.0-rc8-syzkaller-00018-g479174d402bc #0 Not tainted ------------------------------------------------------ syz-executor.0/3818 is trying to acquire lock: ffffffff8c6c9aa8 (zonelist_update_seq.seqcount){...-}-{0:0}, at: __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5571 but task is already holding lock: ffff88802c929418 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x60c/0xe30 kernel/time/timer.c:1096 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&base->lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 lock_timer_base+0x5a/0x1f0 kernel/time/timer.c:999 __mod_timer+0x398/0xe30 kernel/time/timer.c:1072 __queue_delayed_work+0x1a7/0x270 kernel/workqueue.c:1676 queue_delayed_work_on+0x109/0x120 kernel/workqueue.c:1701 psi_task_change+0x1bf/0x2f0 kernel/sched/psi.c:833 psi_enqueue kernel/sched/stats.h:141 [inline] enqueue_task+0x1ec/0x3a0 kernel/sched/core.c:2056 activate_task kernel/sched/core.c:2085 [inline] wake_up_new_task+0x632/0xdb0 kernel/sched/core.c:4706 kernel_clone+0x229/0x980 kernel/fork.c:2702 user_mode_thread+0xb1/0xf0 kernel/fork.c:2747 rest_init+0x27/0x270 init/main.c:694 arch_call_rest_init+0x13/0x1c init/main.c:890 start_kernel+0x477/0x498 init/main.c:1145 secondary_startup_64_no_verify+0xce/0xdb -> #3 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x34/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2f/0x120 kernel/sched/core.c:537 raw_spin_rq_lock kernel/sched/sched.h:1354 [inline] rq_lock kernel/sched/sched.h:1644 [inline] task_fork_fair+0x6c/0x520 kernel/sched/fair.c:11608 sched_cgroup_fork+0x3d1/0x540 kernel/sched/core.c:4650 copy_process+0x4351/0x7190 kernel/fork.c:2370 kernel_clone+0xeb/0x980 kernel/fork.c:2671 user_mode_thread+0xb1/0xf0 kernel/fork.c:2747 rest_init+0x27/0x270 init/main.c:694 arch_call_rest_init+0x13/0x1c init/main.c:890 start_kernel+0x477/0x498 init/main.c:1145 secondary_startup_64_no_verify+0xce/0xdb -> #2 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 try_to_wake_up+0xb2/0x20f0 kernel/sched/core.c:4076 up+0x79/0xb0 kernel/locking/semaphore.c:191 __up_console_sem+0xa4/0xc0 kernel/printk/printk.c:260 __console_unlock kernel/printk/printk.c:2651 [inline] console_unlock+0x4ce/0x600 kernel/printk/printk.c:2862 vga_remove_vgacon drivers/pci/vgaarb.c:189 [inline] vga_remove_vgacon.cold+0x99/0x9e drivers/pci/vgaarb.c:170 virtio_gpu_pci_quirk drivers/gpu/drm/virtio/virtgpu_drv.c:60 [inline] virtio_gpu_probe.cold+0xe3/0x15d drivers/gpu/drm/virtio/virtgpu_drv.c:91 virtio_dev_probe+0x57b/0x870 drivers/virtio/virtio.c:305 call_driver_probe drivers/base/dd.c:560 [inline] really_probe+0x249/0xb90 drivers/base/dd.c:639 __driver_probe_device+0x1df/0x4d0 drivers/base/dd.c:778 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:808 __driver_attach+0x1d4/0x550 drivers/base/dd.c:1190 bus_for_each_dev+0x14b/0x1d0 drivers/base/bus.c:301 bus_add_driver+0x4cd/0x640 drivers/base/bus.c:618 driver_register+0x224/0x3a0 drivers/base/driver.c:246 do_one_initcall+0x141/0x780 init/main.c:1303 do_initcall_level init/main.c:1376 [inline] do_initcalls init/main.c:1392 [inline] do_basic_setup init/main.c:1411 [inline] kernel_init_freeable+0x6ff/0x788 init/main.c:1631 kernel_init+0x1e/0x1d0 init/main.c:1519 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 -> #1 ((console_sem).lock){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 down_trylock+0x12/0x70 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x40/0x120 kernel/printk/printk.c:243 console_trylock kernel/printk/printk.c:2585 [inline] console_trylock_spinning kernel/printk/printk.c:1867 [inline] vprintk_emit+0x16b/0x600 kernel/printk/printk.c:2267 vprintk+0x84/0xa0 kernel/printk/printk_safe.c:50 _printk+0xbe/0xf1 kernel/printk/printk.c:2289 build_zonelists+0x2e7/0x400 mm/page_alloc.c:6503 __build_all_zonelists+0x122/0x180 mm/page_alloc.c:6619 build_all_zonelists_init+0x35/0x12f mm/page_alloc.c:6644 build_all_zonelists+0x123/0x140 mm/page_alloc.c:6677 start_kernel+0xbd/0x498 init/main.c:967 secondary_startup_64_no_verify+0xce/0xdb -> #0 (zonelist_update_seq.seqcount){...-}-{0:0}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 seqcount_lockdep_reader_access include/linux/seqlock.h:102 [inline] read_seqbegin include/linux/seqlock.h:836 [inline] zonelist_iter_begin mm/page_alloc.c:4730 [inline] __alloc_pages_slowpath.constprop.0+0x1ae/0x23d0 mm/page_alloc.c:5052 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5571 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x94/0x390 mm/slab.c:2570 cache_alloc_refill+0x27f/0x380 mm/slab.c:2943 ____cache_alloc mm/slab.c:3019 [inline] ____cache_alloc mm/slab.c:3002 [inline] __do_cache_alloc mm/slab.c:3202 [inline] slab_alloc_node mm/slab.c:3250 [inline] slab_alloc mm/slab.c:3265 [inline] __kmem_cache_alloc_lru mm/slab.c:3442 [inline] kmem_cache_alloc+0x364/0x460 mm/slab.c:3461 kmem_cache_zalloc include/linux/slab.h:679 [inline] fill_pool+0x264/0x5c0 lib/debugobjects.c:168 __debug_object_init+0x7a/0xd10 lib/debugobjects.c:562 debug_object_init lib/debugobjects.c:617 [inline] debug_object_activate+0x330/0x3e0 lib/debugobjects.c:703 debug_timer_activate kernel/time/timer.c:782 [inline] __mod_timer+0x77d/0xe30 kernel/time/timer.c:1103 key_schedule_gc+0x100/0x130 security/keys/gc.c:65 key_revoke+0x281/0x320 security/keys/key.c:1079 keyctl_revoke_key+0xc5/0x130 security/keys/keyctl.c:402 __do_sys_keyctl+0x463/0x610 security/keys/keyctl.c:1886 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: zonelist_update_seq.seqcount --> &rq->__lock --> &base->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&base->lock); lock(&rq->__lock); lock(&base->lock); lock(zonelist_update_seq.seqcount); *** DEADLOCK *** 2 locks held by syz-executor.0/3818: #0: ffff888022f3c798 (&type->lock_class/1){+.+.}-{3:3}, at: key_revoke+0x78/0x320 security/keys/key.c:1069 #1: ffff88802c929418 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x60c/0xe30 kernel/time/timer.c:1096 stack backtrace: CPU: 3 PID: 3818 Comm: syz-executor.0 Not tainted 6.1.0-rc8-syzkaller-00018-g479174d402bc #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 seqcount_lockdep_reader_access include/linux/seqlock.h:102 [inline] read_seqbegin include/linux/seqlock.h:836 [inline] zonelist_iter_begin mm/page_alloc.c:4730 [inline] __alloc_pages_slowpath.constprop.0+0x1ae/0x23d0 mm/page_alloc.c:5052 __alloc_pages+0x4aa/0x5b0 mm/page_alloc.c:5571 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x94/0x390 mm/slab.c:2570 cache_alloc_refill+0x27f/0x380 mm/slab.c:2943 ____cache_alloc mm/slab.c:3019 [inline] ____cache_alloc mm/slab.c:3002 [inline] __do_cache_alloc mm/slab.c:3202 [inline] slab_alloc_node mm/slab.c:3250 [inline] slab_alloc mm/slab.c:3265 [inline] __kmem_cache_alloc_lru mm/slab.c:3442 [inline] kmem_cache_alloc+0x364/0x460 mm/slab.c:3461 kmem_cache_zalloc include/linux/slab.h:679 [inline] fill_pool+0x264/0x5c0 lib/debugobjects.c:168 __debug_object_init+0x7a/0xd10 lib/debugobjects.c:562 debug_object_init lib/debugobjects.c:617 [inline] debug_object_activate+0x330/0x3e0 lib/debugobjects.c:703 debug_timer_activate kernel/time/timer.c:782 [inline] __mod_timer+0x77d/0xe30 kernel/time/timer.c:1103 key_schedule_gc+0x100/0x130 security/keys/gc.c:65 key_revoke+0x281/0x320 security/keys/key.c:1079 keyctl_revoke_key+0xc5/0x130 security/keys/keyctl.c:402 __do_sys_keyctl+0x463/0x610 security/keys/keyctl.c:1886 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fcfc308c0d9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcfc1bfe168 EFLAGS: 00000246 ORIG_RAX: 00000000000000fa RAX: ffffffffffffffda RBX: 00007fcfc31abf80 RCX: 00007fcfc308c0d9 RDX: 0000000000000000 RSI: 000000003520a605 RDI: 0000000000000003 RBP: 00007fcfc30e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffd0b3a2af R14: 00007fcfc1bfe300 R15: 0000000000022000