Oops: general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 0 UID: 0 PID: 6626 Comm: syz.2.223 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:task_cpu include/linux/sched.h:2268 [inline]
RIP: 0010:is_task_rq_idle kernel/sched/core.c:6169 [inline]
RIP: 0010:cookie_equals kernel/sched/core.c:6174 [inline]
RIP: 0010:pick_next_task kernel/sched/core.c:6355 [inline]
RIP: 0010:__schedule+0x4030/0x5550 kernel/sched/core.c:7143
Code: 24 80 00 00 00 e8 80 67 fc f6 48 8b 84 24 80 00 00 00 48 8b 18 4c 8d 7b 14 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 87 04 00 00 45 8b 3f 49 83 ff 08 0f 83 98
RSP: 0018:ffffc9000c63f8c0 EFLAGS: 00010003
RAX: 0000000000000002 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8880b8620c60
RBP: ffffc9000c63faa8 R08: ffffffff8f8d70f7 R09: 1ffffffff1f1ae1e
R10: dffffc0000000000 R11: ffffffff8199beb0 R12: ffff8880b863c658
R13: ffff888125eb8000 R14: 1ffff110170c7922 R15: 0000000000000014
FS:  000055556a59c500(0000) GS:ffff888125eb8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005e818000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7552
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x14f/0x8c0 kernel/entry/common.c:167
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:679
RIP: 0010:check_kcov_mode kernel/kcov.c:-1 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x1f/0xa0 kernel/kcov.c:314
Code: 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d a8 ef b0 10 65 44 8b 05 c8 ef b0 10 41 81 e0 00 00 ff 00 <ba> 00 01 00 00 23 91 f4 0b 00 00 41 89 d1 45 09 c1 74 12 45 85 c0
RSP: 0018:ffffc9000c63fbd8 EFLAGS: 00000246
RAX: ffffffff81b8f18a RBX: 00000000ffffffff RCX: ffff88802cb29f00
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: ffffc9000c63fcf0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f1ae1f R12: ffff88803e0dab48
R13: ffffc9000d63fab8 R14: 00000000ffffffff R15: dffffc0000000000
 futex_wake+0x3ba/0x5e0 kernel/futex/waitwake.c:214
 do_futex+0x4a9/0x4f0 kernel/futex/syscalls.c:138
 __do_sys_futex kernel/futex/syscalls.c:210 [inline]
 __se_sys_futex+0x3a8/0x450 kernel/futex/syscalls.c:191
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f498702ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffccd548908 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f498702ce59
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f49872a5fa8
RBP: 0000000000001e10 R08: 0000000000000001 R09: 0000000000000000
R10: 00007f49872a5fa0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f49872a5fac R14: 00007f49872a5fa8 R15: 00007f49872a5fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:task_cpu include/linux/sched.h:2268 [inline]
RIP: 0010:is_task_rq_idle kernel/sched/core.c:6169 [inline]
RIP: 0010:cookie_equals kernel/sched/core.c:6174 [inline]
RIP: 0010:pick_next_task kernel/sched/core.c:6355 [inline]
RIP: 0010:__schedule+0x4030/0x5550 kernel/sched/core.c:7143
Code: 24 80 00 00 00 e8 80 67 fc f6 48 8b 84 24 80 00 00 00 48 8b 18 4c 8d 7b 14 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <0f> b6 04 08 84 c0 0f 85 87 04 00 00 45 8b 3f 49 83 ff 08 0f 83 98
RSP: 0018:ffffc9000c63f8c0 EFLAGS: 00010003
RAX: 0000000000000002 RBX: 0000000000000000 RCX: dffffc0000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff8880b8620c60
RBP: ffffc9000c63faa8 R08: ffffffff8f8d70f7 R09: 1ffffffff1f1ae1e
R10: dffffc0000000000 R11: ffffffff8199beb0 R12: ffff8880b863c658
R13: ffff888125eb8000 R14: 1ffff110170c7922 R15: 0000000000000014
FS:  000055556a59c500(0000) GS:ffff888125eb8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005e818000 CR4: 00000000003526f0
----------------
Code disassembly (best guess):
   0:	24 80                	and    $0x80,%al
   2:	00 00                	add    %al,(%rax)
   4:	00 e8                	add    %ch,%al
   6:	80 67 fc f6          	andb   $0xf6,-0x4(%rdi)
   a:	48 8b 84 24 80 00 00 	mov    0x80(%rsp),%rax
  11:	00
  12:	48 8b 18             	mov    (%rax),%rbx
  15:	4c 8d 7b 14          	lea    0x14(%rbx),%r15
  19:	4c 89 f8             	mov    %r15,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	0f b6 04 08          	movzbl (%rax,%rcx,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	0f 85 87 04 00 00    	jne    0x4bd
  36:	45 8b 3f             	mov    (%r15),%r15d
  39:	49 83 ff 08          	cmp    $0x8,%r15
  3d:	0f                   	.byte 0xf
  3e:	83                   	.byte 0x83
  3f:	98                   	cwtl