EXT4-fs (sda1): re-mounted. Opts: dax,,errors=continue
EXT4-fs (sda1): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
EXT4-fs (sda1): warning: refusing change of dax flag with busy inodes while remounting
EXT4-fs (sda1): re-mounted. Opts: dax,,errors=continue
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
PGD 1cea41067 P4D 1cea41067 PUD 1baa9a067 PMD 0 
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 27087 Comm: syz-executor0 Not tainted 4.19.0-rc5-next-20180925+ #80
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:          (null)
Code: Bad RIP value.
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
RSP: 0018:ffff88018df672c8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffed0031bece7f RCX: 0000000000001000
RDX: 0000000000000000 RSI: ffff8801cb994530 RDI: ffff8801ce0035c0
RBP: ffff88018df67460 R08: 0000000000000000 R09: ffff88018df67378
R10: ffffed003b585b57 R11: ffff8801dac2dabb R12: 0000000000001000
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
R13: 0000000000001000 R14: ffff8801c7fd6140 R15: dffffc0000000000
FS:  00007fd6ff4ae700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
CR2: ffffffffffffffd6 CR3: 00000001d7fec000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
Call Trace:
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
kobject: 'loop1' (00000000f53466d1): fill_kobj_path: path = '/devices/virtual/block/loop1'
 __generic_file_write_iter+0x26e/0x630 mm/filemap.c:3279
 ext4_file_write_iter+0x390/0x1420 fs/ext4/file.c:266
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
 call_write_iter include/linux/fs.h:1825 [inline]
 do_iter_readv_writev+0x8b0/0xa80 fs/read_write.c:680
 do_iter_write+0x185/0x5f0 fs/read_write.c:959
 vfs_iter_write+0x77/0xb0 fs/read_write.c:972
 iter_file_splice_write+0x90d/0x1050 fs/splice.c:750
 do_splice_from fs/splice.c:852 [inline]
 direct_splice_actor+0x128/0x190 fs/splice.c:1019
 splice_direct_to_actor+0x318/0x8f0 fs/splice.c:974
 do_splice_direct+0x2d4/0x420 fs/splice.c:1062
 do_sendfile+0x62a/0xe20 fs/read_write.c:1440
 __do_sys_sendfile64 fs/read_write.c:1495 [inline]
 __se_sys_sendfile64 fs/read_write.c:1487 [inline]
 __x64_sys_sendfile64+0x15d/0x250 fs/read_write.c:1487
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 1d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd6ff4adc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457579
RDX: 0000000020000180 RSI: 0000000000000009 RDI: 000000000000000a
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000100000001 R11: 0000000000000246 R12: 00007fd6ff4ae6d4
R13: 00000000004c34e4 R14: 00000000004d5298 R15: 00000000ffffffff
Modules linked in:
CR2: 0000000000000000
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
---[ end trace 1b27679635c6aba2 ]---
kobject: 'loop3' (00000000eca497ec): kobject_uevent_env
RIP: 0010:          (null)
kobject: 'loop3' (00000000eca497ec): fill_kobj_path: path = '/devices/virtual/block/loop3'
Code: Bad RIP value.
RSP: 0018:ffff88018df672c8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffed0031bece7f RCX: 0000000000001000
RDX: 0000000000000000 RSI: ffff8801cb994530 RDI: ffff8801ce0035c0
kobject: 'loop2' (00000000d62d581e): kobject_uevent_env
RBP: ffff88018df67460 R08: 0000000000000000 R09: ffff88018df67378
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
R10: ffffed003b585b57 R11: ffff8801dac2dabb R12: 0000000000001000
kobject: 'loop2' (00000000d62d581e): fill_kobj_path: path = '/devices/virtual/block/loop2'
R13: 0000000000001000 R14: ffff8801c7fd6140 R15: dffffc0000000000
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
kobject: 'loop5' (000000000eeeaf25): kobject_uevent_env
FS:  00007fd6ff4ae700(0000) GS:ffff8801dac00000(0000) knlGS:0000000000000000
kobject: 'loop5' (000000000eeeaf25): fill_kobj_path: path = '/devices/virtual/block/loop5'
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd9c18f3e99 CR3: 00000001d7fec000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
kobject: 'kvm' (0000000014e4d062): kobject_uevent_env
kobject: 'loop3' (00000000eca497ec): kobject_uevent_env
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
kobject: 'kvm' (0000000014e4d062): fill_kobj_path: path = '/devices/virtual/misc/kvm'
kobject: 'loop3' (00000000eca497ec): fill_kobj_path: path = '/devices/virtual/block/loop3'
kobject: 'loop1' (00000000f53466d1): kobject_uevent_env
kobject: 'loop1' (00000000f53466d1): fill_kobj_path: path = '/devices/virtual/block/loop1'
kobject: 'loop4' (00000000466c5bc3): kobject_uevent_env