[   12.983780] ------------[ cut here ]------------
[   12.989926] WARNING: CPU: 0 PID: 0 at drivers/gpu/drm/drm_vblank.c:1015 sun4i_tcon_handler+0x6c/0xb0 [sun4i_tcon]
[   13.003112] Modules linked in: ili9488 gpio_backlight mipi_dbi sy8106a_regulator sun8i_dw_hdmi tinydrm backlight mali(O) dw_hdmi ft6236 sun4i_drm sun8i_mixer sun4i_tcon
[   13.022636] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W  O     4.16.0-rc4-sunxi-dirty #1
[   13.034231] Hardware name: Allwinner sun8i Family
[   13.040458] [<c010e6dc>] (unwind_backtrace) from [<c010b948>] (show_stack+0x10/0x14)
[   13.051145] [<c010b948>] (show_stack) from [<c062bca0>] (dump_stack+0x88/0x9c)
[   13.061316] [<c062bca0>] (dump_stack) from [<c011ba38>] (__warn+0xdc/0xf4)
[   13.071152] [<c011ba38>] (__warn) from [<c011bb20>] (warn_slowpath_null+0x40/0x48)
[   13.081730] [<c011bb20>] (warn_slowpath_null) from [<bf000ec0>] (sun4i_tcon_handler+0x6c/0xb0 [sun4i_tcon])
[   13.094606] [<bf000ec0>] (sun4i_tcon_handler [sun4i_tcon]) from [<c0163548>] (__handle_irq_event_percpu+0x50/0x11c)
[   13.108246] [<c0163548>] (__handle_irq_event_percpu) from [<c0163630>] (handle_irq_event_percpu+0x1c/0x58)
[   13.121097] [<c0163630>] (handle_irq_event_percpu) from [<c01636b0>] (handle_irq_event+0x44/0x68)
[   13.133156] [<c01636b0>] (handle_irq_event) from [<c0166c94>] (handle_fasteoi_irq+0xa0/0x164)
[   13.144886] [<c0166c94>] (handle_fasteoi_irq) from [<c01628d4>] (generic_handle_irq+0x24/0x34)
[   13.156748] [<c01628d4>] (generic_handle_irq) from [<c0162e40>] (__handle_domain_irq+0x5c/0xb4)
[   13.168722] [<c0162e40>] (__handle_domain_irq) from [<c0372b88>] (gic_handle_irq+0x4c/0x90)
[   13.180344] [<c0372b88>] (gic_handle_irq) from [<c0101a0c>] (__irq_svc+0x6c/0x90)
[   13.191075] Exception stack(0xc0a01f40 to 0xc0a01f88)
[   13.197776] 1f40: 00000000 00010104 ef7a8398 c01176a0 ffffe000 c0a04c68 c0a04cd4 00000001
[   13.209165] 1f60: c0a597ca c07d0504 c0937a30 00000000 c0a0dd00 c0a01f90 c010871c c0108720
[   13.220538] 1f80: 600f0013 ffffffff
[   13.225608] [<c0101a0c>] (__irq_svc) from [<c0108720>] (arch_cpu_idle+0x38/0x3c)
[   13.236111] [<c0108720>] (arch_cpu_idle) from [<c0153920>] (do_idle+0xdc/0x144)
[   13.246521] [<c0153920>] (do_idle) from [<c0153bf0>] (cpu_startup_entry+0x18/0x1c)
[   13.257196] [<c0153bf0>] (cpu_startup_entry) from [<c0900c4c>] (start_kernel+0x380/0x38c)
[   13.268472] ---[ end trace b8a236ad2f3ce47a ]---