WARNING in unaccount_page_cache_page

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    089cf7f6 Linux 5.3-rc7
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1210a761600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b89bb446a3faaba4
dashboard link: https://syzkaller.appspot.com/bug?extid=fe601f9e887449d40112
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+fe601f9e887449d40112@xxxxxxxxxxxxxxxxxxxxxxxxx

WARNING: CPU: 0 PID: 12560 at mm/filemap.c:220  
unaccount_page_cache_page+0x65b/0xda0 mm/filemap.c:220
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 12560 Comm: syz-executor.2 Not tainted 5.3.0-rc7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x2dc/0x755 kernel/panic.c:219
 __warn.cold+0x20/0x4c kernel/panic.c:576
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:272
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:unaccount_page_cache_page+0x65b/0xda0 mm/filemap.c:220
Code: 00 0f 85 be 06 00 00 49 8b 5d 00 31 ff 48 c1 eb 03 83 e3 01 48 89 de  
e8 c3 25 e4 ff 48 85 db 0f 84 c0 fb ff ff e8 15 24 e4 ff <0f> 0b 48 b8 00  
00 00 00 00 fc ff df 48 8b 55 d0 48 c1 ea 03 80 3c
RSP: 0018:ffff888060b7f9b8 EFLAGS: 00010016
RAX: 0000000000040000 RBX: 0000000000000001 RCX: ffffc9000a781000
RDX: 0000000000001dcb RSI: ffffffff818e513b RDI: 0000000000000007
RBP: ffff888060b7f9f8 R08: ffff8880584de400 R09: fffff940003f9169
R10: fffff940003f9168 R11: ffffea0001fc8b47 R12: ffffea0001fc8b40
R13: ffffea0001fc8b40 R14: ffffea0001fc8b40 R15: ffffea0001fc8b88
 delete_from_page_cache_batch+0x1e9/0x1170 mm/filemap.c:350
 truncate_inode_pages_range+0x622/0x1740 mm/truncate.c:366
 blkdev_fallocate+0x23a/0x410 fs/block_dev.c:2081
 vfs_fallocate+0x4aa/0xa50 fs/open.c:309
 ksys_fallocate+0x58/0xa0 fs/open.c:332
 __do_sys_fallocate fs/open.c:340 [inline]
 __se_sys_fallocate fs/open.c:338 [inline]
 __x64_sys_fallocate+0x97/0xf0 fs/open.c:338
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd75e4bfc78 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459879
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000004
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000369e5d84 R11: 0000000000000246 R12: 00007fd75e4c06d4
R13: 00000000004bffbd R14: 00000000004d1fc0 R15: 00000000ffffffff
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..


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