syzbot

 exit_mm kernel/exit.c:501 [inline]
 do_exit+0xabc/0x2a30 kernel/exit.c:812
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x47f/0x2160 kernel/signal.c:2868
 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302
------------[ cut here ]------------
WARNING: CPU: 1 PID: 28130 at mm/huge_memory.c:2301 unmap_page mm/huge_memory.c:2301 [inline]
WARNING: CPU: 1 PID: 28130 at mm/huge_memory.c:2301 split_huge_page_to_list+0x24ff/0x3bb0 mm/huge_memory.c:2676
Modules linked in:
CPU: 1 PID: 28130 Comm: syz-executor.3 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unmap_page mm/huge_memory.c:2301 [inline]
RIP: 0010:split_huge_page_to_list+0x24ff/0x3bb0 mm/huge_memory.c:2676
Code: 89 de e8 24 5b b5 ff 84 db 0f 85 7d e1 ff ff e8 d7 54 b5 ff 48 c7 c6 60 5c 98 89 48 89 ef e8 18 1d e9 ff c6 05 03 15 99 0b 01 <0f> 0b e9 5b e1 ff ff bb 02 00 00 00 e9 cd f0 ff ff e8 ab 54 b5 ff
RSP: 0018:ffffc9000a0ef288 EFLAGS: 00010246
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc9000f7ff000
RDX: 0000000000040000 RSI: ffffffff81c0b718 RDI: 0000000000000003
RBP: ffffea0002458000 R08: 0000000000000024 R09: 00000000ffffffff
R10: ffffffff88f44b19 R11: 00000000ffffffff R12: ffff888010e6d2d8
R13: ffffea0002458008 R14: ffffea0002458000 R15: 0000000000000000
FS:  00007f669dab1700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffa393e1000 CR3: 000000002ee5b000 CR4: 0000000000350ee0
Call Trace:
 split_huge_page include/linux/huge_mm.h:192 [inline]
 deferred_split_scan+0x5fa/0xbd0 mm/huge_memory.c:2836
 do_shrink_slab+0x42d/0xbd0 mm/vmscan.c:758
 shrink_slab+0x17c/0x6e0 mm/vmscan.c:918
 drop_slab_node+0x9c/0x160 mm/vmscan.c:953
 drop_slab+0x97/0x130 mm/vmscan.c:963
 drop_caches_sysctl_handler+0xf6/0x110 fs/drop_caches.c:66
 proc_sys_call_handler+0x346/0x630 fs/proc/proc_sysctl.c:586
 call_write_iter include/linux/fs.h:2163 [inline]
 do_iter_readv_writev+0x472/0x750 fs/read_write.c:729
 do_iter_write+0x188/0x710 fs/read_write.c:855
 vfs_iter_write+0x70/0xa0 fs/read_write.c:896
 iter_file_splice_write+0x71b/0xc60 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x110/0x180 fs/splice.c:936
 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891
 do_splice_direct+0x1b3/0x280 fs/splice.c:979
 do_sendfile+0xae9/0x1240 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1314 [inline]
 __se_sys_sendfile64 fs/read_write.c:1300 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1300
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f66a053a739
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:00007f669dab1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f66a063ef80 RCX: 00007f66a053a739
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004
RBP: 00007f66a0594cc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 00007f66a063ef80
R13: 00007fff069bf54f R14: 00007f669dab1300 R15: 0000000000022000