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: 1 PID: 11862 Comm: syz-executor.0 Not tainted 4.19.205-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:enqueue_entity+0x3d/0x3850 kernel/sched/fair.c:3946
Code: 55 48 89 fd 53 48 83 ec 60 83 f8 01 48 8d 47 40 41 0f 95 c5 48 89 c2 48 89 44 24 28 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 3f 28 00 00 48 8b 5d 40 48 39 cb 0f 85 5a 0d 00
RSP: 0018:ffff88806b8c76b8 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff888000156540
RDX: 0000000000000008 RSI: ffff888000156540 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8c664058 R09: ffffffff8c66404f
R10: ffffffff8c664057 R11: ffffffff8c66405b R12: 0000000000000009
R13: dffffc0000000000 R14: 0000000000000009 R15: ffff888000156540
FS:  00007f29172b6700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e4b41 CR3: 00000000a3423000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 enqueue_task_fair+0x12e/0x2270 kernel/sched/fair.c:5177
 ttwu_activate kernel/sched/core.c:1639 [inline]
 ttwu_do_activate+0xce/0x1e0 kernel/sched/core.c:1698
 ttwu_queue kernel/sched/core.c:1843 [inline]
 try_to_wake_up+0x700/0x1050 kernel/sched/core.c:2052
 wake_up_process kernel/sched/core.c:2124 [inline]
 wake_up_q+0x82/0xe0 kernel/sched/core.c:442
 __mutex_unlock_slowpath+0x2be/0x610 kernel/locking/mutex.c:1260
 fb_open+0x252/0x430 drivers/video/fbdev/core/fbmem.c:1473
 chrdev_open+0x266/0x770 fs/char_dev.c:423
 do_dentry_open+0x4aa/0x1160 fs/open.c:796
 do_last fs/namei.c:3421 [inline]
 path_openat+0x793/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f29172b6188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: ffffffffffffff9c
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffc3020e51f R14: 00007f29172b6300 R15: 0000000000022000
Modules linked in:

======================================================
----------------
Code disassembly (best guess):
   0:	55                   	push   %rbp
   1:	48 89 fd             	mov    %rdi,%rbp
   4:	53                   	push   %rbx
   5:	48 83 ec 60          	sub    $0x60,%rsp
   9:	83 f8 01             	cmp    $0x1,%eax
   c:	48 8d 47 40          	lea    0x40(%rdi),%rax
  10:	41 0f 95 c5          	setne  %r13b
  14:	48 89 c2             	mov    %rax,%rdx
  17:	48 89 44 24 28       	mov    %rax,0x28(%rsp)
  1c:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  23:	fc ff df
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 3f 28 00 00    	jne    0x2873
  34:	48 8b 5d 40          	mov    0x40(%rbp),%rbx
  38:	48 39 cb             	cmp    %rcx,%rbx
  3b:	0f                   	.byte 0xf
  3c:	85 5a 0d             	test   %ebx,0xd(%rdx)