general protection fault in set_next_entity

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b9959c7a filldir[64]: remove WARN_ON_ONCE() for bad direct..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13ed2540e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=e0ac4d9b35046343
dashboard link: https://syzkaller.appspot.com/bug?extid=788bb62fbd6b685f88b7
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [dvh...@infradead.org linux-...@vger.kernel.org
mi...@redhat.com pet...@infradead.org tg...@linutronix.de]

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+788bb6...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 14226 Comm: syz-executor.3 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:set_next_entity+0x2c/0x940 kernel/sched/fair.c:4156
Code: 00 00 00 00 00 fc ff df 55 48 89 e5 41 57 41 56 41 55 41 54 49 89 fc
48 8d 7e 40 53 48 89 f3 48 89 fa 48 83 ec 20 48 c1 ea 03 <0f> b6 04 02 84
c0 74 08 3c 03 0f 8e ac 04 00 00 8b 4b 40 4d 8d bc
RSP: 0018:ffff88805ebd77e8 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880ae834d80
RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000040
RBP: ffff88805ebd7830 R08: 0000000000000004 R09: ffffed100bd7aee5
R10: ffffed100bd7aee4 R11: 0000000000000003 R12: ffff8880ae834d80
R13: dffffc0000000000 R14: ffff8880ae834d80 R15: ffff8880ae834d18
FS: 0000000002640940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000068 CR3: 000000005eb1a000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
pick_next_task_fair+0x2f4/0xc60 kernel/sched/fair.c:6835
pick_next_task kernel/sched/core.c:3941 [inline]
__schedule+0x1362/0x1e70 kernel/sched/core.c:4039
schedule+0xd9/0x260 kernel/sched/core.c:4136
freezable_schedule include/linux/freezer.h:172 [inline]
futex_wait_queue_me+0x2c4/0x590 kernel/futex.c:2627
futex_wait+0x217/0x5d0 kernel/futex.c:2733
do_futex+0x175/0x1de0 kernel/futex.c:3644
__do_sys_futex kernel/futex.c:3705 [inline]
__se_sys_futex kernel/futex.c:3673 [inline]
__x64_sys_futex+0x3f7/0x590 kernel/futex.c:3673
do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffe5e483088 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00000000000003e8 RCX: 0000000000459a59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bfd4
RBP: 000000000000002d R08: ffffffffffffffff R09: ffffffffffffffff
R10: 00007ffe5e483160 R11: 0000000000000246 R12: 000000000075bfc8
R13: 00000000000ade45 R14: 00000000000ade72 R15: 000000000075bfd4
Modules linked in:

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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.