------------[ cut here ]------------
[PLANE:35:plane-0] pixel format with alpha exposed but blend mode not setup
WARNING: drivers/gpu/drm/drm_mode_config.c:872 at validate_blend_mode_for_alpha_formats drivers/gpu/drm/drm_mode_config.c:872 [inline], CPU#1: syz.3.185/4480
WARNING: drivers/gpu/drm/drm_mode_config.c:872 at drm_mode_config_validate+0xa64/0x1914 drivers/gpu/drm/drm_mode_config.c:938, CPU#1: syz.3.185/4480
Modules linked in:
CPU: 1 UID: 0 PID: 4480 Comm: syz.3.185 Tainted: G        W           syzkaller #0 PREEMPT 
Tainted: [W]=WARN
Hardware name: linux,dummy-virt (DT)
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : validate_blend_mode_for_alpha_formats drivers/gpu/drm/drm_mode_config.c:872 [inline]
pc : drm_mode_config_validate+0xa64/0x1914 drivers/gpu/drm/drm_mode_config.c:938
lr : validate_blend_mode_for_alpha_formats drivers/gpu/drm/drm_mode_config.c:872 [inline]
lr : drm_mode_config_validate+0xa64/0x1914 drivers/gpu/drm/drm_mode_config.c:938
sp : ffff8000a08a7870
x29: ffff8000a08a7880 x28: ffff00002113b080 x27: 0000000000000001
x26: dfff800000000000 x25: ffff00003f5347c0 x24: ffff00002113b170
x23: ffff00002113b178 x22: 0000000000000003 x21: ffff60000422762e
x20: 0000000000000000 x19: 1fffe0000422762f x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: ffff8000877cb698
x14: 00000000000017d0 x13: ffff800089ecdca8 x12: ffff60000d7f6a22
x11: 1fffe0000d7f6a21 x10: ffff60000d7f6a21 x9 : dfff800000000000
x8 : ffff8000a08a73a0 x7 : ffff8000a08a7520 x6 : ffff8000a08a74c0
x5 : ffff8000a08a7400 x4 : 0000000000000005 x3 : 1fffe0000d7f5b5d
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000153a5700
Call trace:
 validate_blend_mode_for_alpha_formats drivers/gpu/drm/drm_mode_config.c:872 [inline] (P)
 drm_mode_config_validate+0xa64/0x1914 drivers/gpu/drm/drm_mode_config.c:938 (P)
 drm_dev_register+0x3d0/0x7e0 drivers/gpu/drm/drm_drv.c:1077
 vkms_create+0x378/0x450 drivers/gpu/drm/vkms/vkms_drv.c:208
 device_enabled_store+0x1c8/0x22c drivers/gpu/drm/vkms/vkms_configfs.c:719
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x244/0x398 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x4c0/0xbac fs/read_write.c:687
 ksys_write+0xf0/0x1e0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __arm64_sys_write+0x70/0xa0 fs/read_write.c:747
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x74/0x240 arch/arm64/kernel/syscall.c:49
 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:121
 do_el0_svc_compat+0x40/0x58 arch/arm64/kernel/syscall.c:146
 el0_svc_compat+0x54/0x264 arch/arm64/kernel/entry-common.c:909
 el0t_32_sync_handler+0x88/0xac arch/arm64/kernel/entry-common.c:927
 el0t_32_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:595
irq event stamp: 3152
hardirqs last  enabled at (3151): [<ffff8000802d5f94>] raw_spin_rq_unlock_irq kernel/sched/sched.h:1698 [inline]
hardirqs last  enabled at (3151): [<ffff8000802d5f94>] finish_lock_switch kernel/sched/core.c:5251 [inline]
hardirqs last  enabled at (3151): [<ffff8000802d5f94>] finish_task_switch.isra.0+0x1e4/0x9f0 kernel/sched/core.c:5369
hardirqs last disabled at (3152): [<ffff8000859a90d0>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:445
softirqs last  enabled at (3108): [<ffff80008023b5b8>] softirq_handle_end kernel/softirq.c:491 [inline]
softirqs last  enabled at (3108): [<ffff80008023b5b8>] handle_softirqs+0xa98/0x1048 kernel/softirq.c:673
softirqs last disabled at (3093): [<ffff8000800103d4>] __do_softirq+0x14/0x20 kernel/softirq.c:679
---[ end trace 0000000000000000 ]---
[drm] Initialized vkms 1.0.0 for mydev on minor 2
faux_driver mydev: [drm] fb1: vkmsdrmfb frame buffer device