BUG: unable to handle page fault for address: ffffea600036f008 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 13fff8067 P4D 13fff8067 PUD 0 Oops: Oops: 0000 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 6345 Comm: syz.2.129 Not tainted 6.16.0-rc6-next-20250716-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:_compound_head include/linux/page-flags.h:284 [inline] RIP: 0010:move_pages+0xbe6/0x1430 mm/userfaultfd.c:1824 Code: c1 ec 06 4b 8d 1c 2c 48 83 c3 08 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 9a 30 f4 ff <48> 8b 1b 48 89 de 48 83 e6 01 31 ff e8 59 70 8f ff 48 89 d8 48 83 RSP: 0018:ffffc900030578a8 EFLAGS: 00010246 RAX: 1ffffd4c0006de01 RBX: ffffea600036f008 RCX: dffffc0000000000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200060af00 R12: 000000600036f000 R13: ffffea0000000000 R14: 300018000dbc01fd R15: 00002000003ab000 FS: 00007f62ba9af6c0(0000) GS:ffff8881258aa000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffea600036f008 CR3: 0000000022bf2000 CR4: 00000000003526f0 Call Trace: userfaultfd_move fs/userfaultfd.c:1923 [inline] userfaultfd_ioctl+0x2e8b/0x4c80 fs/userfaultfd.c:2046 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:598 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:584 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f62b9b8e929 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:00007f62ba9af038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f62b9db6160 RCX: 00007f62b9b8e929 RDX: 0000200000000180 RSI: 00000000c028aa05 RDI: 0000000000000006 RBP: 00007f62b9c10ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f62b9db6160 R15: 00007ffc5d64bec8 Modules linked in: CR2: ffffea600036f008 ---[ end trace 0000000000000000 ]--- RIP: 0010:_compound_head include/linux/page-flags.h:284 [inline] RIP: 0010:move_pages+0xbe6/0x1430 mm/userfaultfd.c:1824 Code: c1 ec 06 4b 8d 1c 2c 48 83 c3 08 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 9a 30 f4 ff <48> 8b 1b 48 89 de 48 83 e6 01 31 ff e8 59 70 8f ff 48 89 d8 48 83 RSP: 0018:ffffc900030578a8 EFLAGS: 00010246 RAX: 1ffffd4c0006de01 RBX: ffffea600036f008 RCX: dffffc0000000000 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200060af00 R12: 000000600036f000 R13: ffffea0000000000 R14: 300018000dbc01fd R15: 00002000003ab000 FS: 00007f62ba9af6c0(0000) GS:ffff8881258aa000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffea600036f008 CR3: 0000000022bf2000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: c1 ec 06 shr $0x6,%esp 3: 4b 8d 1c 2c lea (%r12,%r13,1),%rbx 7: 48 83 c3 08 add $0x8,%rbx b: 48 89 d8 mov %rbx,%rax e: 48 c1 e8 03 shr $0x3,%rax 12: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 19: fc ff df 1c: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) 20: 74 08 je 0x2a 22: 48 89 df mov %rbx,%rdi 25: e8 9a 30 f4 ff call 0xfff430c4 * 2a: 48 8b 1b mov (%rbx),%rbx <-- trapping instruction 2d: 48 89 de mov %rbx,%rsi 30: 48 83 e6 01 and $0x1,%rsi 34: 31 ff xor %edi,%edi 36: e8 59 70 8f ff call 0xff8f7094 3b: 48 89 d8 mov %rbx,%rax 3e: 48 rex.W 3f: 83 .byte 0x83