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generic_make_request: Trying to write to read-only block-device nullb0 (partno 0)
WARNING: CPU: 0 PID: 20509 at block/blk-core.c:801 bio_check_ro block/blk-core.c:801 [inline]
WARNING: CPU: 0 PID: 20509 at block/blk-core.c:801 generic_make_request_checks+0x1c8a/0x2140 block/blk-core.c:906
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 20509 Comm: blkid Not tainted 5.0.0-rc7-next-20190222 #41
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x2cb/0x65c kernel/panic.c:214
 __warn.cold+0x20/0x45 kernel/panic.c:571
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:bio_check_ro block/blk-core.c:801 [inline]
RIP: 0010:generic_make_request_checks+0x1c8a/0x2140 block/blk-core.c:906
Code: 00 00 44 8b ab b4 04 00 00 48 8d b5 78 ff ff ff 4c 89 ff e8 58 80 05 00 48 c7 c7 20 2d a1 87 48 89 c6 44 89 ea e8 e4 cd 26 fe <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 80 3c 02
RSP: 0018:ffff88808bacf340 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8880a34d4e80 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815ac616 RDI: ffffed1011759e5a
RBP: ffff88808bacf440 R08: ffff88808ee2a2c0 R09: ffffed1015d05011
R10: ffffed1015d05010 R11: ffff8880ae828087 R12: ffff88809ffb3d48
R13: 0000000000000000 R14: 0000000000000001 R15: ffff88809ffb3d40
 generic_make_request+0x24c/0x12d0 block/blk-core.c:1032
 submit_bio+0xba/0x480 block/blk-core.c:1197
 submit_bh_wbc+0x5f7/0x7f0 fs/buffer.c:3128
 __block_write_full_page+0x771/0x1020 fs/buffer.c:1803
 block_write_full_page+0x21f/0x270 fs/buffer.c:2993
 blkdev_writepage+0x25/0x30 fs/block_dev.c:618
 __writepage+0x67/0xe0 mm/page-writeback.c:2300
 write_cache_pages+0x8af/0x1560 mm/page-writeback.c:2235
 generic_writepages mm/page-writeback.c:2326 [inline]
 generic_writepages+0xed/0x160 mm/page-writeback.c:2315
 blkdev_writepages+0x1e/0x30 fs/block_dev.c:2002
 do_writepages+0xfc/0x2a0 mm/page-writeback.c:2341
 __filemap_fdatawrite_range+0x26d/0x340 mm/filemap.c:413
 __filemap_fdatawrite mm/filemap.c:421 [inline]
 filemap_fdatawrite mm/filemap.c:426 [inline]
 filemap_write_and_wait mm/filemap.c:607 [inline]
 filemap_write_and_wait+0x47/0xd0 mm/filemap.c:602
 __sync_blockdev fs/block_dev.c:500 [inline]
 sync_blockdev fs/block_dev.c:509 [inline]
 __blkdev_put+0x204/0x810 fs/block_dev.c:1834
 blkdev_put+0x98/0x560 fs/block_dev.c:1903
 blkdev_close+0x8b/0xb0 fs/block_dev.c:1910
 __fput+0x2e5/0x8d0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x14a/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fcb8c7302b0
Code: 40 75 0b 31 c0 48 83 c4 08 e9 0c ff ff ff 48 8d 3d c5 32 08 00 e8 c0 07 02 00 83 3d 45 a3 2b 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ce 8a 01 00 48 89 04 24
RSP: 002b:00007ffc2fccfad8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fcb8c7302b0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000028 R09: 0000000001680000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000023f6030
R13: 0000000000000000 R14: 0000000000000003 R15: 0000000000000005
Kernel Offset: disabled
Rebooting in 86400 seconds..