BUG: unable to handle kernel paging request in vga16fb

BUG: unable to handle kernel paging request in vga16fb_imageblit
Status: upstream: reported on 2020/04/16 00:46
Reported-by: syzbot+9594fea1f21d8be845b8@syzkaller.appspotmail.com
First crash: 327d, last: 47d

similar bugs (4):
Kernel	Title	Count	Last	Reported	Patched	Status
linux-4.19	BUG: unable to handle kernel paging request in vga16fb_imageblit	4	341d	437d	0/1	auto-closed as invalid on 2020/07/31 03:49
upstream	BUG: unable to handle kernel paging request in vga16fb_imageblit	1	439d	438d	0/21	auto-closed as invalid on 2020/04/23 17:11
upstream	BUG: unable to handle kernel paging request in vga16fb_imageblit (2)	20	58d	305d	0/21	upstream: reported on 2020/05/08 07:07
linux-4.19	BUG: unable to handle kernel paging request in vga16fb_imageblit (2)	6	28d	127d	0/1	upstream: reported on 2020/11/01 15:15

Sample crash report:

PM: Marking nosave pages: [mem 0x00000000-0x00000fff]
PM: Marking nosave pages: [mem 0x0009f000-0x000fffff]
PM: Marking nosave pages: [mem 0xbfffd000-0xffffffff]
PM: Basic memory bitmaps created
PM: Basic memory bitmaps freed
BUG: unable to handle kernel paging request at ffff888001000040
IP: writeb arch/x86/include/asm/io.h:65 [inline]
IP: vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1177 [inline]
IP: vga16fb_imageblit+0xb68/0x2140 drivers/video/fbdev/vga16fb.c:1261
PGD c9c6067 P4D c9c6067 PUD c9c7067 PMD 80000000010001e1 
Oops: 0003 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 8431 Comm: syz-executor.3 Not tainted 4.14.216-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888091ada380 task.stack: ffff88808de78000
RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline]
RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1177 [inline]
RIP: 0010:vga16fb_imageblit+0xb68/0x2140 drivers/video/fbdev/vga16fb.c:1261
RSP: 0018:ffff88808de7f558 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888001000045 RCX: 0000000000000004
RDX: ffff888001000040 RSI: ffffffff833b5727 RDI: ffff888238858994
RBP: dffffc0000000000 R08: 0000000000003133 R09: 0000000000000010
R10: 0000000000000005 R11: 0000000000000000 R12: ffff888238858995
R13: ffff88808de7f6f0 R14: ffff888001000041 R15: ffff888001000040
FS:  00007f8c25264700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888001000040 CR3: 0000000091757000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline]
 bit_putcs+0x81e/0xc30 drivers/video/fbdev/core/bitblit.c:188
 fbcon_putcs+0x2fe/0x480 drivers/video/fbdev/core/fbcon.c:1247
 do_update_region+0x34b/0x5b0 drivers/tty/vt/vt.c:373
 redraw_screen+0x56e/0x790 drivers/tty/vt/vt.c:705
 fbcon_blank+0x986/0xd50 drivers/video/fbdev/core/fbcon.c:2201
 do_unblank_screen+0x1fd/0x4e0 drivers/tty/vt/vt.c:3937
 vt_ioctl+0xf43/0x1d50 drivers/tty/vt/vt_ioctl.c:498
 tty_ioctl+0x50f/0x13c0 drivers/tty/tty_io.c:2661
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45e219
RSP: 002b:00007f8c25263c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045e219
RDX: 0000000000000000 RSI: 0000000000004b3a RDI: 0000000000000004
RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007ffecc53ab8f R14: 00007f8c252649c0 R15: 000000000119bf8c
Code: 49 83 c4 01 48 89 f8 48 89 f9 49 83 c6 01 48 c1 e8 03 83 e1 07 0f b6 04 28 38 c8 7f 08 84 c0 0f 85 0f 0f 00 00 41 0f b6 44 24 ff <88> 02 49 39 de 75 c3 48 8b 74 24 18 48 01 74 24 08 e8 f2 cd 19 
RIP: writeb arch/x86/include/asm/io.h:65 [inline] RSP: ffff88808de7f558
RIP: vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1177 [inline] RSP: ffff88808de7f558
RIP: vga16fb_imageblit+0xb68/0x2140 drivers/video/fbdev/vga16fb.c:1261 RSP: ffff88808de7f558
CR2: ffff888001000040
---[ end trace c044015ab81b5322 ]---

Crashes (7):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-linux-4-14	2021/01/20 08:31	linux-4.14.y	2762b48e	63631df1	.config	log	report	info	BUG: unable to handle kernel paging request in vga16fb_imageblit
ci2-linux-4-14	2020/12/28 05:56	linux-4.14.y	3f2ecb86	2242f77f	.config	log	report	info
ci2-linux-4-14	2020/12/26 19:19	linux-4.14.y	3f2ecb86	821e0b09	.config	log	report	info
ci2-linux-4-14	2020/12/20 23:42	linux-4.14.y	3f2ecb86	04201c06	.config	log	report	info
ci2-linux-4-14	2020/09/28 03:50	linux-4.14.y	cbfa1702	5dd8aee8	.config	log	report	info
ci2-linux-4-14	2020/06/03 01:19	linux-4.14.y	4f68020f	f3ba1b5b	.config	log	report
ci2-linux-4-14	2020/04/16 00:45	linux-4.14.y	c10b57a5	3f3c5574	.config	log	report