bisecting fixing commit since b850307b279cbd12ab8c654d1a3dfe55319cc475
building syzkaller on 6e569755ce2f0efcad474398871ff75693e770fc
testing commit b850307b279cbd12ab8c654d1a3dfe55319cc475 with gcc (GCC) 8.1.0
kernel signature: feeb1b29e5d78fc94c7e61d17d6e23dfec443094da70c3cd86b0493fcc5dca99
all runs: crashed: general protection fault in do_con_write
testing current HEAD 87335852c5d9ec629f80bb2257b9a9945962b719
testing commit 87335852c5d9ec629f80bb2257b9a9945962b719 with gcc (GCC) 8.1.0
kernel signature: d6f16821cda172d5969eeb1e8b2b1cd62c0d194897fc94e7dcc0c6fb7749f765
all runs: crashed: divide error in fbcon_init
revisions tested: 2, total time: 23m9.560103213s (build: 17m10.100190637s, test: 5m28.158019439s)
the crash still happens on HEAD
commit msg: Linux 4.14.209
crash: divide error in fbcon_init
batman_adv: batadv0: Interface activated: batadv_slave_1
IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_batadv: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready
divide error: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 7790 Comm: syz-executor.0 Not tainted 4.14.209-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880a2596340 task.stack: ffff8880a1308000
RIP: 0010:fbcon_init+0x6ee/0x1d50 drivers/video/fbdev/core/fbcon.c:1065
RSP: 0018:ffff8880a130f698 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880b56c6240 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 1ffff11016ad8cbe RDI: ffff8880b56c65f4
RBP: ffff8880a130f728 R08: ffffffff8a4467c0 R09: 0000000000000000
R10: ffff8880b56c6574 R11: ffff8880b56c6578 R12: ffff888239212640
R13: 0000000000000014 R14: ffff8880b1a19580 R15: ffff8880b1a19738
FS:  00007f0ab4602700(0000) GS:ffff8880ba900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0132408db8 CR3: 00000000a1074000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 visual_init+0x314/0x5d0 drivers/tty/vt/vt.c:746
 vc_allocate+0x2d3/0x700 drivers/tty/vt/vt.c:802
 con_install+0x4d/0x4c0 drivers/tty/vt/vt.c:2899
 tty_driver_install_tty drivers/tty/tty_io.c:1225 [inline]
 tty_init_dev+0xdb/0x350 drivers/tty/tty_io.c:1338
 tty_open_by_driver drivers/tty/tty_io.c:1973 [inline]
 tty_open+0x608/0x8e0 drivers/tty/tty_io.c:2021
 chrdev_open+0x1e9/0x5b0 fs/char_dev.c:423
 do_dentry_open+0x3e4/0xde0 fs/open.c:777
 vfs_open+0xfc/0x240 fs/open.c:888
 do_last fs/namei.c:3428 [inline]
 path_openat+0xb73/0x27a0 fs/namei.c:3569
 do_filp_open+0x16b/0x220 fs/namei.c:3603
 do_sys_open+0x1c2/0x340 fs/open.c:1081
 SYSC_open fs/open.c:1099 [inline]
 SyS_open+0x19/0x20 fs/open.c:1094
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x416921
RSP: 002b:00007f0ab46017a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 000000000050ada0 RCX: 0000000000416921
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00007f0ab46017d0
RBP: 000000000078c040 R08: 0000000000000000 R09: 000000000000000e
R10: 0000000000000064 R11: 0000000000000293 R12: 00000000ffffffff
R13: 0000000000000c5b R14: 00000000004cebf0 R15: 00007f0ab46026d4
Code: 89 d0 48 ba 00 00 00 00 00 fc ff df 48 8b 75 b0 48 c1 ee 03 0f b6 14 16 84 d2 74 09 80 fa 03 0f 8e 6f 10 00 00 31 d2 48 8b 7d a0 <f7> b3 b0 03 00 00 48 89 fa 48 c1 ea 03 41 89 c0 48 b8 00 00 00 
RIP: fbcon_init+0x6ee/0x1d50 drivers/video/fbdev/core/fbcon.c:1065 RSP: ffff8880a130f698
---[ end trace f10f5e54bc44f3b8 ]---