RAX: ffffffffffffffda RBX: 0000000000012e80 RCX: 000000000045de59
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fd5094dfca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 00007ffe638637af R14: 00007fd5094e09c0 R15: 000000000118bf2c
BUG: unable to handle kernel NULL pointer dereference at 0000000000000120
IP: set_bit arch/x86/include/asm/bitops.h:81 [inline]
IP: cpumask_set_cpu include/linux/cpumask.h:283 [inline]
IP: blk_mq_map_swqueue+0x253/0x990 block/blk-mq.c:2171
PGD b4f19067 P4D b4f19067 PUD 92b50067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 26218 Comm: syz-executor.1 Not tainted 4.14.202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88805e65e580 task.stack: ffff888093b30000
RIP: 0010:set_bit arch/x86/include/asm/bitops.h:81 [inline]
RIP: 0010:cpumask_set_cpu include/linux/cpumask.h:283 [inline]
RIP: 0010:blk_mq_map_swqueue+0x253/0x990 block/blk-mq.c:2171
RSP: 0018:ffff888093b37a80 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff8880ae8f4540 RCX: ffffc900062cd000
RDX: 0000000000040000 RSI: ffffffff83129023 RDI: ffffffff88cbcd68
RBP: 0000000000000001 R08: ffff8880ae855d00 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff88823854dd00 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007fd5094e0700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000120 CR3: 0000000099107000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 blk_mq_queue_reinit block/blk-mq.c:2512 [inline]
 __blk_mq_update_nr_hw_queues block/blk-mq.c:2750 [inline]
 blk_mq_update_nr_hw_queues+0x246/0x3e0 block/blk-mq.c:2760
 nbd_start_device+0x1d7/0xc90 drivers/block/nbd.c:1192
 nbd_start_device_ioctl drivers/block/nbd.c:1243 [inline]
 __nbd_ioctl drivers/block/nbd.c:1325 [inline]
 nbd_ioctl+0x3a8/0xa80 drivers/block/nbd.c:1365
 __blkdev_driver_ioctl block/ioctl.c:297 [inline]
 blkdev_ioctl+0x540/0x1830 block/ioctl.c:594
 block_ioctl+0xd9/0x120 fs/block_dev.c:1893
 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: 0033:0x45de59
RSP: 002b:00007fd5094dfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000012e80 RCX: 000000000045de59
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fd5094dfca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 00007ffe638637af R14: 00007fd5094e09c0 R15: 000000000118bf2c
Code: 4d 8d 34 c8 4c 89 f1 48 c1 e9 03 42 80 3c 39 00 0f 85 37 05 00 00 83 fd 07 4d 8b 36 0f 87 42 04 00 00 48 89 04 24 e8 7d ac 44 fe <f0> 4d 0f ab a6 20 01 00 00 49 8d be 78 01 00 00 48 8b 04 24 48 
RIP: set_bit arch/x86/include/asm/bitops.h:81 [inline] RSP: ffff888093b37a80
RIP: cpumask_set_cpu include/linux/cpumask.h:283 [inline] RSP: ffff888093b37a80
RIP: blk_mq_map_swqueue+0x253/0x990 block/blk-mq.c:2171 RSP: ffff888093b37a80
CR2: 0000000000000120
---[ end trace ddb9049a889ef10d ]---