syzbot

loop0: detected capacity change from 0 to 4096
BUG: unable to handle page fault for address: ffffed1106d27487
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 5ffcd067 P4D 5ffcd067 PUD 0 
Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI
CPU: 0 UID: 16895 PID: 5317 Comm: syz.0.0 Not tainted 6.14.0-rc6-syzkaller-00016-g0fed89a961ea #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline]
RIP: 0010:tif_test_bit include/linux/thread_info.h:192 [inline]
RIP: 0010:tif_need_resched include/linux/thread_info.h:208 [inline]
RIP: 0010:need_resched include/linux/sched.h:2149 [inline]
RIP: 0010:__schedule_loop kernel/sched/core.c:6844 [inline]
RIP: 0010:schedule+0x155/0x320 kernel/sched/core.c:6857
Code: c1 eb 03 eb 0a 48 f7 45 00 08 00 00 00 74 2c bf 01 00 00 00 e8 cc 55 85 f5 31 ff e8 15 b2 ff ff bf 01 00 00 00 e8 5b 57 85 f5 <42> 80 3c 23 00 74 d4 48 89 ef e8 ec f8 1e f6 eb ca 4c 8d 75 2c 4d
RSP: 0018:ffffc9000d4ef110 EFLAGS: 00010297
RAX: 0000000080000001 RBX: 1ffff11006d27488 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffff88803693a440 R08: ffff888043cc0003 R09: 1ffff11008798000
R10: dffffc0000000000 R11: ffffed1008798001 R12: dffffc00ffffffff
R13: 0000000000000000 R14: ffffffff8c0a2b10 R15: ffff88803693b6c8
FS:  00007f63bf9306c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed1106d27487 CR3: 0000000043622000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 io_schedule+0x8d/0x110 kernel/sched/core.c:7690
 folio_wait_bit_common+0x839/0xee0 mm/filemap.c:1318
 __folio_lock mm/filemap.c:1665 [inline]
 folio_lock include/linux/pagemap.h:1163 [inline]
 __filemap_get_folio+0x14e/0xae0 mm/filemap.c:1918
 filemap_lock_folio include/linux/pagemap.h:800 [inline]
 collapse_file mm/khugepaged.c:1930 [inline]
 hpage_collapse_scan_file+0x17fd/0x5230 mm/khugepaged.c:2352
 madvise_collapse+0x5f4/0xd00 mm/khugepaged.c:2794
 madvise_vma_behavior mm/madvise.c:1330 [inline]
 madvise_walk_vmas mm/madvise.c:1511 [inline]
 do_madvise+0x183b/0x4db0 mm/madvise.c:1698
 __do_sys_madvise mm/madvise.c:1714 [inline]
 __se_sys_madvise mm/madvise.c:1712 [inline]
 __x64_sys_madvise+0xa6/0xc0 mm/madvise.c:1712
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f63beb8d169
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f63bf930038 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00007f63beda5fa0 RCX: 00007f63beb8d169
RDX: 0000000000000019 RSI: 0000000000800000 RDI: 00004000007fe000
RBP: 00007f63bec0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f63beda5fa0 R15: 00007fffe2b33b18
 </TASK>
Modules linked in:
CR2: ffffed1106d27487
---[ end trace 0000000000000000 ]---
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline]
RIP: 0010:tif_test_bit include/linux/thread_info.h:192 [inline]
RIP: 0010:tif_need_resched include/linux/thread_info.h:208 [inline]
RIP: 0010:need_resched include/linux/sched.h:2149 [inline]
RIP: 0010:__schedule_loop kernel/sched/core.c:6844 [inline]
RIP: 0010:schedule+0x155/0x320 kernel/sched/core.c:6857
Code: c1 eb 03 eb 0a 48 f7 45 00 08 00 00 00 74 2c bf 01 00 00 00 e8 cc 55 85 f5 31 ff e8 15 b2 ff ff bf 01 00 00 00 e8 5b 57 85 f5 <42> 80 3c 23 00 74 d4 48 89 ef e8 ec f8 1e f6 eb ca 4c 8d 75 2c 4d
RSP: 0018:ffffc9000d4ef110 EFLAGS: 00010297
RAX: 0000000080000001 RBX: 1ffff11006d27488 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffff88803693a440 R08: ffff888043cc0003 R09: 1ffff11008798000
R10: dffffc0000000000 R11: ffffed1008798001 R12: dffffc00ffffffff
R13: 0000000000000000 R14: ffffffff8c0a2b10 R15: ffff88803693b6c8
FS:  00007f63bf9306c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed1106d27487 CR3: 0000000043622000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	c1 eb 03             	shr    $0x3,%ebx
   3:	eb 0a                	jmp    0xf
   5:	48 f7 45 00 08 00 00 	testq  $0x8,0x0(%rbp)
   c:	00
   d:	74 2c                	je     0x3b
   f:	bf 01 00 00 00       	mov    $0x1,%edi
  14:	e8 cc 55 85 f5       	call   0xf58555e5
  19:	31 ff                	xor    %edi,%edi
  1b:	e8 15 b2 ff ff       	call   0xffffb235
  20:	bf 01 00 00 00       	mov    $0x1,%edi
  25:	e8 5b 57 85 f5       	call   0xf5855785
* 2a:	42 80 3c 23 00       	cmpb   $0x0,(%rbx,%r12,1) <-- trapping instruction
  2f:	74 d4                	je     0x5
  31:	48 89 ef             	mov    %rbp,%rdi
  34:	e8 ec f8 1e f6       	call   0xf61ef925
  39:	eb ca                	jmp    0x5
  3b:	4c 8d 75 2c          	lea    0x2c(%rbp),%r14
  3f:	4d                   	rex.WRB