syzbot

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WARNING: CPU: 1 PID: 2201 at kernel/sched/deadline.c:344 setup_new_dl_entity kernel/sched/deadline.c:344 [inline]
WARNING: CPU: 1 PID: 2201 at kernel/sched/deadline.c:344 switched_to_dl kernel/sched/deadline.c:1861 [inline]
WARNING: CPU: 1 PID: 2201 at kernel/sched/deadline.c:344 switched_to_dl+0x651/0x870 kernel/sched/deadline.c:1848
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 2201 Comm: syz-executor.5 Not tainted 4.9.165+ #26
 ffff88019fb67b58 ffffffff81b4ba01 0000000000000000 ffffffff82a39ba0
 00000000ffffffff 0000000000000001 0000000000000009 ffff88019fb67c38
 ffffffff813f90fa 0000000041b58ab3 ffffffff82e2e772 ffffffff813f8f21
Call Trace:
 [<ffffffff81b4ba01>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b4ba01>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff813f90fa>] panic+0x1d9/0x3bd kernel/panic.c:180
 [<ffffffff813f933b>] __warn.cold+0x2f/0x2f kernel/panic.c:546
 [<ffffffff810dac4d>] warn_slowpath_null+0x2d/0x40 kernel/panic.c:589
 [<ffffffff811e82f1>] setup_new_dl_entity kernel/sched/deadline.c:344 [inline]
 [<ffffffff811e82f1>] switched_to_dl kernel/sched/deadline.c:1861 [inline]
 [<ffffffff811e82f1>] switched_to_dl+0x651/0x870 kernel/sched/deadline.c:1848
 [<ffffffff8116ad46>] check_class_changed kernel/sched/core.c:950 [inline]
 [<ffffffff8116ad46>] __sched_setscheduler+0x906/0x3060 kernel/sched/core.c:4389
 [<ffffffff8117ae9c>] sched_setattr kernel/sched/core.c:4442 [inline]
 [<ffffffff8117ae9c>] SYSC_sched_setattr kernel/sched/core.c:4616 [inline]
 [<ffffffff8117ae9c>] SyS_sched_setattr+0x25c/0x3d0 kernel/sched/core.c:4595
 [<ffffffff810056bd>] do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285
 [<ffffffff8280c153>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..