Hello, syzbot found the following issue on: HEAD commit: 736b6d81d93c Add linux-next specific files for 20221123 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=13780ab1880000 kernel config: https://syzkaller.appspot.com/x/.config?x=84cf3b793149c9bf dashboard link: https://syzkaller.appspot.com/bug?extid=62debf5fcd57b5a592e1 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/b1f9b28c7e06/disk-736b6d81.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/139697685008/vmlinux-736b6d81.xz kernel image: https://storage.googleapis.com/syzbot-assets/6ff62230b292/bzImage-736b6d81.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+62debf5fcd57b5a592e1@xxxxxxxxxxxxxxxxxxxxxxxxx QNX4 filesystem 0.2.3 registered. qnx6: QNX6 filesystem 1.0.0 registered. fuse: init (API version 7.38) orangefs_debugfs_init: called with debug mask: :none: :0: orangefs_init: module version upstream loaded JFS: nTxBlock = 8192, nTxLock = 65536 SGI XFS with ACLs, security attributes, realtime, quota, no debug enabled 9p: Installing v9fs 9p2000 file system support NILFS version 2 loaded befs: version: 0.9.3 ocfs2: Registered cluster interface o2cb ocfs2: Registered cluster interface user OCFS2 User DLM kernel interface loaded gfs2: GFS2 installed ceph: loaded (mds proto 32) NET: Registered PF_ALG protocol family xor: automatically using best checksumming function avx async_tx: api initialized (async) Key type asymmetric registered Asymmetric key parser 'x509' registered Asymmetric key parser 'pkcs8' registered Key type pkcs7_test registered alg: self-tests for CTR-KDF (hmac(sha256)) passed Block layer SCSI generic (bsg) driver version 0.4 loaded (major 240) io scheduler mq-deadline registered io scheduler kyber registered io scheduler bfq registered input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0 ACPI: button: Power Button [PWRF] input: Sleep Button as /devices/LNXSYSTM:00/LNXSLPBN:00/input/input1 ACPI: button: Sleep Button [SLPF] ACPI: \_SB_.LNKC: Enabled at IRQ 11 virtio-pci 0000:00:03.0: virtio_pci: leaving for legacy driver ACPI: \_SB_.LNKD: Enabled at IRQ 10 virtio-pci 0000:00:04.0: virtio_pci: leaving for legacy driver ACPI: \_SB_.LNKB: Enabled at IRQ 10 virtio-pci 0000:00:06.0: virtio_pci: leaving for legacy driver virtio-pci 0000:00:07.0: virtio_pci: leaving for legacy driver N_HDLC line discipline registered with maxframe=4096 Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled 00:03: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A 00:04: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A 00:05: ttyS2 at I/O 0x3e8 (irq = 6, base_baud = 115200) is a 16550A 00:06: ttyS3 at I/O 0x2e8 (irq = 7, base_baud = 115200) is a 16550A Non-volatile memory driver v1.3 Linux agpgart interface v0.103 ACPI: bus type drm_connector registered [drm] Initialized vgem 1.0.0 20120112 for vgem on minor 0 [drm] Initialized vkms 1.0.0 20180514 for vkms on minor 1 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at drivers/video/fbdev/core/fb_defio.c:340 fb_deferred_io_schedule_flush+0x9f/0xf0 drivers/video/fbdev/core/fb_defio.c:340 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc6-next-20221123-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:fb_deferred_io_schedule_flush+0x9f/0xf0 drivers/video/fbdev/core/fb_defio.c:340 Code: c1 e8 03 80 3c 30 00 75 38 48 8b 35 43 81 27 0a bf 08 00 00 00 e8 c1 05 06 fd 48 83 c4 10 5b 5d e9 66 76 34 fd e8 61 76 34 fd <0f> 0b 48 83 c4 10 5b 5d e9 54 76 34 fd e8 6f 97 82 fd e9 7a ff ff RSP: 0000:ffffc900000672d8 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88801e2d0000 RCX: 0000000000000000 RDX: ffff888140150000 RSI: ffffffff844c552f RDI: ffff88801e2d0418 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffffff9133aa47 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000008 R14: ffff88801e281940 R15: 00000000000000d0 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff88823ffff000 CR3: 000000000c48e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> drm_fb_helper_damage drivers/gpu/drm/drm_fb_helper.c:602 [inline] drm_fb_helper_sys_imageblit+0x2c9/0x380 drivers/gpu/drm/drm_fb_helper.c:883 drm_fbdev_fb_imageblit+0x17d/0x260 drivers/gpu/drm/drm_fbdev_generic.c:157 soft_cursor+0x514/0xa30 drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0xf13/0x17a0 drivers/video/fbdev/core/bitblit.c:377 fbcon_cursor+0x3e0/0x550 drivers/video/fbdev/core/fbcon.c:1330 hide_cursor+0x85/0x280 drivers/tty/vt/vt.c:907 redraw_screen+0x5b8/0x740 drivers/tty/vt/vt.c:1012 vc_do_resize+0xed6/0x1170 drivers/tty/vt/vt.c:1342 fbcon_init+0x1061/0x1920 drivers/video/fbdev/core/fbcon.c:1125 visual_init+0x326/0x620 drivers/tty/vt/vt.c:1074 do_bind_con_driver.isra.0+0x52f/0x910 drivers/tty/vt/vt.c:3694 do_take_over_console+0x450/0x5c0 drivers/tty/vt/vt.c:4273 do_fbcon_takeover+0xe8/0x210 drivers/video/fbdev/core/fbcon.c:530 do_fb_registered drivers/video/fbdev/core/fbcon.c:3008 [inline] fbcon_fb_registered+0x34a/0x460 drivers/video/fbdev/core/fbcon.c:3028 do_register_framebuffer drivers/video/fbdev/core/fbmem.c:1597 [inline] register_framebuffer+0x6b7/0xb60 drivers/video/fbdev/core/fbmem.c:1703 __drm_fb_helper_initial_config_and_unlock+0xe30/0x13e0 drivers/gpu/drm/drm_fb_helper.c:2117 drm_fb_helper_initial_config drivers/gpu/drm/drm_fb_helper.c:2183 [inline] drm_fb_helper_initial_config+0x4a/0x60 drivers/gpu/drm/drm_fb_helper.c:2175 drm_fbdev_client_hotplug+0x2b4/0x3d0 drivers/gpu/drm/drm_fbdev_generic.c:406 drm_fbdev_generic_setup+0x165/0x440 drivers/gpu/drm/drm_fbdev_generic.c:488 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:208 [inline] vkms_init+0x569/0x5ed drivers/gpu/drm/vkms/vkms_drv.c:233 do_one_initcall+0x141/0x790 init/main.c:1306 do_initcall_level init/main.c:1379 [inline] do_initcalls init/main.c:1395 [inline] do_basic_setup init/main.c:1414 [inline] kernel_init_freeable+0x6f9/0x782 init/main.c:1634 kernel_init+0x1e/0x1d0 init/main.c:1522 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> --- This report is generated by a bot. 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