------------[ cut here ]------------
WARNING: kernel/sched/core.c:10569 at sched_mm_cid_fork+0x81/0xcc0 kernel/sched/core.c:10569, CPU#1: kworker/u32:6/15077
Modules linked in:
CPU: 1 UID: 0 PID: 15077 Comm: kworker/u32:6 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:sched_mm_cid_fork+0x81/0xcc0 kernel/sched/core.c:10569
Code: 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 2a 0a 00 00 81 bd d4 15 00 00 00 00 00 80 74 04 90 <0f> 0b 90 49 8d 84 24 c0 01 00 00 31 f6 4d 8d ac 24 80 01 00 00 48
RSP: 0018:ffffc900059d7d00 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff888029744980 RCX: ffffffff823d9361
RDX: 1ffff110052e89e3 RSI: ffffffff823d936f RDI: ffff888029744f18
RBP: ffff888029744980 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880297454b0 R12: 0000000000000000
R13: ffffed1008175c85 R14: 00000000fffffffe R15: ffffffff8e621ca0
FS:  0000000000000000(0000) GS:ffff8880d69fd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001200 CR3: 0000000027bce000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 bprm_execve fs/exec.c:1776 [inline]
 bprm_execve+0x4ff/0x1620 fs/exec.c:1729
 kernel_execve+0x2ef/0x3b0 fs/exec.c:1919
 call_usermodehelper_exec_async+0x255/0x4c0 kernel/umh.c:109
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>