BUG: unable to handle page fault for address: 0000000000004007
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 908d5067 P4D 908d5067 PUD 90fcb067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8999 Comm: kworker/u4:13 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:preempt_schedule_notrace_thunk+0x16/0x31 arch/x86/entry/thunk_64.S:41
Code: 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 d5 f5 06 eb 18 55 48 89 e5 57 00 77 00 00 77 00 00 00 77 00 70 07 77 00 70 07 77 <00> 70 07 77 00 70 07 77 00 70 07 77 00 70 07 77 00 70 07 77 00 70
RSP: 0018:ffffc900178d7b30 EFLAGS: 00010246
RAX: 0000000000004000 RBX: 0000000000000000 RCX: ffffffff87f64d06
RDX: ffffed1008804401 RSI: 0000000000000008 RDI: ffff888044022000
RBP: ffffc900178d7b78 R08: 0000000000000000 R09: ffff888044022007
R10: ffffed1008804400 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880a6d733a8
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000004007 CR3: 00000000a2c94000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 trace_lock_acquire include/trace/events/lock.h:13 [inline]
 lock_acquire+0x3b5/0xae0 kernel/locking/lockdep.c:4980
 rcu_lock_acquire include/linux/rcupdate.h:241 [inline]
 rcu_read_lock include/linux/rcupdate.h:634 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline]
 batadv_nc_worker+0x12d/0xe50 net/batman-adv/network-coding.c:718
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Modules linked in:
CR2: 0000000000004007
---[ end trace ed570ae39afa0ecc ]---
RIP: 0010:preempt_schedule_notrace_thunk+0x16/0x31 arch/x86/entry/thunk_64.S:41
Code: 57 56 52 51 50 41 50 41 51 41 52 41 53 e8 a3 d5 f5 06 eb 18 55 48 89 e5 57 00 77 00 00 77 00 00 00 77 00 70 07 77 00 70 07 77 <00> 70 07 77 00 70 07 77 00 70 07 77 00 70 07 77 00 70 07 77 00 70
RSP: 0018:ffffc900178d7b30 EFLAGS: 00010246
RAX: 0000000000004000 RBX: 0000000000000000 RCX: ffffffff87f64d06
RDX: ffffed1008804401 RSI: 0000000000000008 RDI: ffff888044022000
RBP: ffffc900178d7b78 R08: 0000000000000000 R09: ffff888044022007
R10: ffffed1008804400 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: ffff8880a6d733a8
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000004007 CR3: 00000000a2c94000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400