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WARNING: CPU: 0 PID: 1814 at drivers/gpu/drm/vkms/vkms_crtc.c:21 vkms_vblank_simulate+0x23e/0x242 drivers/gpu/drm/vkms/vkms_crtc.c:21
Modules linked in:
CPU: 0 PID: 1814 Comm: kworker/u4:3 Not tainted 5.12.0-rc8-syzkaller-00194-g18a3c5f7abfd #0
Hardware name: riscv-virtio,qemu (DT)
epc : vkms_vblank_simulate+0x23e/0x242 drivers/gpu/drm/vkms/vkms_crtc.c:21
 ra : vkms_vblank_simulate+0x23e/0x242 drivers/gpu/drm/vkms/vkms_crtc.c:21
epc : ffffffe000f5c40a ra : ffffffe000f5c40a sp : ffffffe00ac0b300
 gp : ffffffe004588b78 tp : ffffffe005ed5f00 t0 : 0000000000046000
 t1 : 0000000000000001 t2 : 0000000000000000 s0 : ffffffe00ac0b340
 s1 : ffffffe00a8e1e58 a0 : 0000000000000000 a1 : 00000000000f0000
 a2 : 0000000000010101 a3 : ffffffe000f5c40a a4 : ffffffe005ed5f00
 a5 : 0000000000000000 a6 : 0000000000f00000 a7 : ffffffe000f5c224
 s2 : ffffffe00a8e0d30 s3 : 0000000000000002 s4 : 0000000000fe4c00
 s5 : 0000000000001000 s6 : ffffffe067d481c8 s7 : 0000000000000000
 s8 : ffffffe067d48190 s9 : ffffffe00a8e1e90 s10: ffffffe067d48100
 s11: ffffffe000f5c1cc t3 : 0a4e80e38745b900 t4 : ffffffc401581696
 t5 : ffffffc401581697 t6 : 0000000000000007
status: 0000000000000100 badaddr: 0000000000000000 cause: 0000000000000003
Call Trace:
[<ffffffe000f5c40a>] vkms_vblank_simulate+0x23e/0x242 drivers/gpu/drm/vkms/vkms_crtc.c:21
[<ffffffe0001217ee>] __run_hrtimer kernel/time/hrtimer.c:1537 [inline]
[<ffffffe0001217ee>] __hrtimer_run_queues+0x4aa/0x9ba kernel/time/hrtimer.c:1601
[<ffffffe0001224de>] hrtimer_interrupt+0x1e6/0x50a kernel/time/hrtimer.c:1663
[<ffffffe001da6e9c>] riscv_timer_interrupt+0x5c/0x6a drivers/clocksource/timer-riscv.c:88
[<ffffffe0000ef812>] handle_percpu_devid_irq+0x17e/0x2be kernel/irq/chip.c:930
[<ffffffe0000e46fe>] generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
[<ffffffe0000e46fe>] generic_handle_irq kernel/irq/irqdesc.c:652 [inline]
[<ffffffe0000e46fe>] __handle_domain_irq+0x13e/0x1ea kernel/irq/irqdesc.c:689
[<ffffffe000a91d96>] handle_domain_irq include/linux/irqdesc.h:176 [inline]
[<ffffffe000a91d96>] riscv_intc_irq+0x82/0xcc drivers/irqchip/irq-riscv-intc.c:40
[<ffffffe000005586>] ret_from_exception+0x0/0x14
[<ffffffe00010691c>] rcu_nocb_unlock_irqrestore kernel/rcu/tree_plugin.h:2801 [inline]
[<ffffffe00010691c>] rcu_core+0xb94/0xd9a kernel/rcu/tree.c:2786