__invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]
 el0_svc_common.constprop.0+0x60/0x120 arch/arm64/kernel/syscall.c:129
 do_el0_svc+0x74/0x90 arch/arm64/kernel/syscall.c:168
 el0_svc+0x2c/0x54 arch/arm64/kernel/entry-common.c:416
 el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:432
 el0_sync+0x18c/0x1c0 arch/arm64/kernel/entry.S:699
------------[ cut here ]------------
WARNING: CPU: 1 PID: 9367 at block/genhd.c:620 __device_add_disk+0x458/0x4a0 block/genhd.c:632
Modules linked in:
CPU: 1 PID: 9367 Comm: syz-executor.1 Not tainted 5.12.0-rc1-syzkaller-00022-gf69d02e37a85 #0
Hardware name: linux,dummy-virt (DT)
pstate: 60400009 (nZCv daif +PAN -UAO -TCO BTYPE=--)
pc : __device_add_disk+0x458/0x4a0 block/genhd.c:620
lr : __device_add_disk+0x34c/0x4a0 block/genhd.c:619
sp : ffff800017abbcd0
x29: ffff800017abbcd0 x28: f5ff000029988000 
x27: 0000000000000000 x26: ffff800013ce3000 
x25: fcff00000c04f000 x24: f5ff00002998420c 
x23: 0000000000000001 x22: 0000000000000000 
x21: 0000000000000000 x20: f6ff00000457f0e0 
x19: f5ff000029984200 x18: 00000000fffffffb 
x17: 0000000000000000 x16: 0000000000000000 
x15: 0000000000000020 x14: ffffffffffffffff 
x13: 0000000000000d12 x12: ffff800017abb670 
x11: ffff800013a0b570 x10: 00000000ffffe000 
x9 : ffff800013a0b570 x8 : ffff80001395b570 
x7 : ffff800013a0b570 x6 : 0000000000000000 
x5 : ffff00007fbd7948 x4 : 0000000000015ff5 
x3 : 0000000000000000 x2 : 0000000000000000 
x1 : f5ff000029988000 x0 : fffffffffffffff4 
Call trace:
 __device_add_disk+0x458/0x4a0 block/genhd.c:632
 device_add_disk+0x14/0x20 block/genhd.c:642
 add_disk include/linux/genhd.h:231 [inline]
 loop_add+0x1f4/0x260 drivers/block/loop.c:2172
 loop_control_ioctl drivers/block/loop.c:2268 [inline]
 loop_control_ioctl+0xc4/0x1b0 drivers/block/loop.c:2250
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __arm64_sys_ioctl+0xa8/0xec fs/ioctl.c:739
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]
 el0_svc_common.constprop.0+0x60/0x120 arch/arm64/kernel/syscall.c:129
 do_el0_svc+0x74/0x90 arch/arm64/kernel/syscall.c:168
 el0_svc+0x2c/0x54 arch/arm64/kernel/entry-common.c:416
 el0_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:432
 el0_sync+0x18c/0x1c0 arch/arm64/kernel/entry.S:699