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WARNING: CPU: 1 PID: 3067 at drivers/gpu/drm/vkms/vkms_crtc.c:21 vkms_vblank_simulate+0x150/0x154 drivers/gpu/drm/vkms/vkms_crtc.c:21
Modules linked in:
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 3067 Comm: udevd Not tainted 5.12.0-rc3-syzkaller #0
Hardware name: ARM-Versatile Express
Backtrace: 
[<81802550>] (dump_backtrace) from [<818027c4>] (show_stack+0x18/0x1c arch/arm/kernel/traps.c:252)
 r7:00000080 r6:600f0193 r5:00000000 r4:82b58344
[<818027ac>] (show_stack) from [<81809e98>] (__dump_stack lib/dump_stack.c:79 [inline])
[<818027ac>] (show_stack) from [<81809e98>] (dump_stack+0xb8/0xe8 lib/dump_stack.c:120)
[<81809de0>] (dump_stack) from [<81803358>] (panic+0x130/0x378 kernel/panic.c:231)
 r7:81f48198 r6:82a390a4 r5:00000000 r4:82c6b0d0
[<81803228>] (panic) from [<802446f4>] (__warn+0xb0/0x164 kernel/panic.c:605)
 r3:82a2248c r2:00000000 r1:00000000 r0:81f48198
 r7:00000015
[<80244644>] (__warn) from [<81803608>] (warn_slowpath_fmt+0x68/0xd4 kernel/panic.c:628)
 r7:809fa964 r6:00000015 r5:81fcbd70 r4:00000000
[<818035a4>] (warn_slowpath_fmt) from [<809fa964>] (vkms_vblank_simulate+0x150/0x154 drivers/gpu/drm/vkms/vkms_crtc.c:21)
 r8:00fe4c00 r7:844c0720 r6:82a22498 r5:00000000 r4:844c1390
[<809fa814>] (vkms_vblank_simulate) from [<80307ebc>] (__run_hrtimer kernel/time/hrtimer.c:1537 [inline])
[<809fa814>] (vkms_vblank_simulate) from [<80307ebc>] (__hrtimer_run_queues+0xd4/0x690 kernel/time/hrtimer.c:1601)
 r9:857f2000 r8:ddfdb3e0 r7:ddfdb380 r6:82a22498 r5:00000000 r4:844c1390
[<80307de8>] (__hrtimer_run_queues) from [<80308da0>] (hrtimer_interrupt+0x14c/0x2e0 kernel/time/hrtimer.c:1663)
 r10:ddfdb4d8 r9:ddfdb498 r8:ddfdb458 r7:ddfdb4a0 r6:ddfdb4e0 r5:200f0193
 r4:ddfdb380
[<80308c54>] (hrtimer_interrupt) from [<8114c308>] (timer_handler drivers/clocksource/arm_arch_timer.c:647 [inline])
[<80308c54>] (hrtimer_interrupt) from [<8114c308>] (arch_timer_handler_virt+0x30/0x38 drivers/clocksource/arm_arch_timer.c:658)
 r10:857f3d30 r9:857f3d98 r8:857f3d00 r7:8348d940 r6:82a22c34 r5:0000001c
 r4:8348b000
[<8114c2d8>] (arch_timer_handler_virt) from [<802df904>] (handle_percpu_devid_irq+0xa4/0x19c kernel/irq/chip.c:930)
[<802df860>] (handle_percpu_devid_irq) from [<802d8730>] (generic_handle_irq_desc include/linux/irqdesc.h:158 [inline])
[<802df860>] (handle_percpu_devid_irq) from [<802d8730>] (generic_handle_irq kernel/irq/irqdesc.c:652 [inline])
[<802df860>] (handle_percpu_devid_irq) from [<802d8730>] (__handle_domain_irq+0xb0/0x120 kernel/irq/irqdesc.c:689)
 r10:857f3d30 r9:857f3d98 r8:00000001 r7:00000000 r6:828ad498 r5:00000000
 r4:828ad498 r3:00010001
[<802d8680>] (__handle_domain_irq) from [<8088af70>] (handle_domain_irq include/linux/irqdesc.h:176 [inline])
[<802d8680>] (__handle_domain_irq) from [<8088af70>] (gic_handle_irq+0x84/0xac drivers/irqchip/irq-gic.c:370)
 r10:0000000c r9:857f2000 r8:e000200c r7:828ad4bc r6:e0002000 r5:857f3d98
 r4:82a22c34
[<8088aeec>] (gic_handle_irq) from [<80200abc>] (__irq_svc+0x5c/0x94 arch/arm/kernel/entry-armv.S:205)
Exception stack(0x857f3d98 to 0x857f3de0)
3d80:                                                       00000001 00000003
3da0: 00000001 857f2000 ddfe3a40 835e2738 8046d9a4 82a22498 0018f988 81f9f564
3dc0: 0000000c 857f3e04 857f3dd8 857f3de8 8181daac 802eb5f8 200f0013 ffffffff
 r9:857f2000 r8:0018f988 r7:857f3dcc r6:ffffffff r5:200f0013 r4:802eb5f8
[<802eb5b8>] (rcu_lockdep_current_cpu_online) from [<802e7e00>] (rcu_read_lock_held_common kernel/rcu/update.c:112 [inline])
[<802eb5b8>] (rcu_lockdep_current_cpu_online) from [<802e7e00>] (rcu_read_lock_held_common kernel/rcu/update.c:102 [inline])
[<802eb5b8>] (rcu_lockdep_current_cpu_online) from [<802e7e00>] (rcu_read_lock_sched_held+0x30/0x7c kernel/rcu/update.c:123)
 r4:82bfd3d6
[<802e7dd0>] (rcu_read_lock_sched_held) from [<802bfa2c>] (trace_lock_release include/trace/events/lock.h:58 [inline])
[<802e7dd0>] (rcu_read_lock_sched_held) from [<802bfa2c>] (lock_release+0x4c0/0x534 kernel/locking/lockdep.c:5521)
[<802bf56c>] (lock_release) from [<8046d9e4>] (__might_fault mm/memory.c:5021 [inline])
[<802bf56c>] (lock_release) from [<8046d9e4>] (__might_fault+0xa4/0xb4 mm/memory.c:5006)
 r10:0000000c r9:81f9f564 r8:0018f988 r7:00000020 r6:0000000c r5:00000000
 r4:857f2000
[<8046d940>] (__might_fault) from [<804f436c>] (filldir64+0x184/0x260 fs/readdir.c:336)
 r5:857f3f58 r4:ffffe000
[<804f41e8>] (filldir64) from [<805b8e04>] (dir_emit include/linux/fs.h:3521 [inline])
[<804f41e8>] (filldir64) from [<805b8e04>] (kernfs_fop_readdir+0x118/0x288 fs/kernfs/dir.c:1692)
 r10:00000000 r9:00004c5a r8:82b2f2ec r7:00000000 r6:31d98417 r5:857f3f58
 r4:84518f70
[<805b8cec>] (kernfs_fop_readdir) from [<804f40e4>] (iterate_dir+0x8c/0x190 fs/readdir.c:67)
 r10:000000d9 r9:861240bc r8:86124000 r7:857f3f58 r6:86cdc280 r5:00000001
 r4:00000000
[<804f4058>] (iterate_dir) from [<804f45ec>] (__do_sys_getdents64 fs/readdir.c:366 [inline])
[<804f4058>] (iterate_dir) from [<804f45ec>] (sys_getdents64+0x6c/0x13c fs/readdir.c:351)
 r9:857f2000 r8:80200224 r7:86cdc280 r6:00008000 r5:0018f8d4 r4:86cdc280
[<804f4580>] (sys_getdents64) from [<80200060>] (ret_fast_syscall+0x0/0x2c arch/arm/mm/proc-v7.S:64)
Exception stack(0x857f3fa8 to 0x857f3ff0)
3fa0:                   0018f8d0 0018f8d4 0000000e 0018f8f0 00008000 00000000
3fc0: 0018f8d0 0018f8d4 76efc840 000000d9 0018f8f0 0000c2df 7e8c452c 000000fd
3fe0: 000562ac 7e8c450c 76b9bd28 76b9bc50
 r9:857f2000 r8:80200224 r7:000000d9 r6:76efc840 r5:0018f8d4 r4:0018f8d0
Rebooting in 86400 seconds..