syzbot

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WARNING: kernel/sched/core.c:10569 at sched_mm_cid_fork+0x66/0xc30 kernel/sched/core.c:10569, CPU#0: kworker/u4:4/5674
Modules linked in:
CPU: 0 UID: 0 PID: 5674 Comm: kworker/u4:4 Not tainted syzkaller #0 PREEMPT(full) 
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+0x66/0xc30 kernel/sched/core.c:10569
Code: 4c 8b 3b 4d 85 ff 74 21 49 8d 9d d4 15 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 0f 85 13 0a 00 00 31 c0 3b 03 70 04 90 <0f> 0b 90 49 8d 9f 00 01 00 00 49 8d bf c0 01 00 00 48 89 7c 24 20
RSP: 0000:ffffc900036cfbd8 EFLAGS: 00010246
RAX: 1ffff110067b79e3 RBX: ffff888033dbcf18 RCX: ffff888033dbc980
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888033dbc980
RBP: ffffc900036cfd68 R08: ffffffff8e295e83 R09: 1ffffffff1c52bd0
R10: dffffc0000000000 R11: fffffbfff1c52bd1 R12: ffff888033dbc980
R13: ffff888033dbc980 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88808d22f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ad913e000 CR3: 0000000041a50000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 bprm_execve+0xd88/0x1400 fs/exec.c:1776
 kernel_execve+0x8f0/0x9f0 fs/exec.c:1919
 call_usermodehelper_exec_async+0x210/0x360 kernel/umh.c:109
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>