Re: [syzbot] kernel BUG in __filemap_get_folio

[syzbot <syzbot+cf4cf13056f85dec2c40@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in __filemap_get_folio

 free_contig_range+0xb1/0x180 mm/page_alloc.c:9418
 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x2a51/0x2ae3 mm/debug_vm_pgtable.c:1332
 do_one_initcall+0x103/0x650 init/main.c:1298
 do_initcall_level init/main.c:1371 [inline]
 do_initcalls init/main.c:1387 [inline]
 do_basic_setup init/main.c:1406 [inline]
 kernel_init_freeable+0x6b1/0x73a init/main.c:1613
 kernel_init+0x1a/0x1d0 init/main.c:1502
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
------------[ cut here ]------------
kernel BUG at mm/filemap.c:1972!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 4282 Comm: syz-executor.1 Not tainted 5.18.0-rc3-syzkaller-00007-g559089e0a93d-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__filemap_get_folio+0xc65/0xf00 mm/filemap.c:1972
Code: db 45 31 f6 e9 fd f5 ff ff 44 8b 6c 24 10 48 89 eb e9 f0 f5 ff ff e8 2a f2 d8 ff 48 c7 c6 80 d9 d5 89 48 89 df e8 6b 8d 0e 00 <0f> 0b e8 14 f2 d8 ff 48 89 df 31 db e8 4a af 03 00 e9 78 f7 ff ff
RSP: 0018:ffffc900037b78b0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffea00017c8800 RCX: 0000000000000000
RDX: ffff8880763fc140 RSI: ffffffff819f5bf5 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000018 R09: 00000000ffffffff
R10: ffffffff891d5eec R11: 00000000ffffffff R12: 00000000000001c0
R13: 0000000000000182 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f807ec16700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd7f356c058 CR3: 0000000078894000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pagecache_get_page+0x2e/0x290 mm/folio-compat.c:126
 shmem_getpage_gfp+0x471/0x2370 mm/shmem.c:1812
 shmem_getpage mm/shmem.c:149 [inline]
 shmem_write_begin+0xff/0x1e0 mm/shmem.c:2446
 generic_perform_write+0x249/0x560 mm/filemap.c:3788
 __generic_file_write_iter+0x2aa/0x4d0 mm/filemap.c:3916
 generic_file_write_iter+0xd7/0x220 mm/filemap.c:3948
 call_write_iter include/linux/fs.h:2050 [inline]
 new_sync_write+0x38a/0x560 fs/read_write.c:504
 vfs_write+0x7c0/0xac0 fs/read_write.c:591
 ksys_write+0x127/0x250 fs/read_write.c:644
 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: 0033:0x7f807da890e9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f807ec16168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f807db9bf60 RCX: 00007f807da890e9
RDX: 000000000208e24b RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007f807dae308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcdf2c068f R14: 00007f807ec16300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__filemap_get_folio+0xc65/0xf00 mm/filemap.c:1972
Code: db 45 31 f6 e9 fd f5 ff ff 44 8b 6c 24 10 48 89 eb e9 f0 f5 ff ff e8 2a f2 d8 ff 48 c7 c6 80 d9 d5 89 48 89 df e8 6b 8d 0e 00 <0f> 0b e8 14 f2 d8 ff 48 89 df 31 db e8 4a af 03 00 e9 78 f7 ff ff
RSP: 0018:ffffc900037b78b0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffffea00017c8800 RCX: 0000000000000000
RDX: ffff8880763fc140 RSI: ffffffff819f5bf5 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000018 R09: 00000000ffffffff
R10: ffffffff891d5eec R11: 00000000ffffffff R12: 00000000000001c0
R13: 0000000000000182 R14: 0000000000000000 R15: dffffc0000000000
FS:  00007f807ec16700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1a16b6c058 CR3: 0000000078894000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit:         559089e0 vmalloc: replace VM_NO_HUGE_VMAP with VM_ALLO..
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/
console output: https://syzkaller.appspot.com/x/log.txt?x=17b87e0cf00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=dd7c9a79dfcfa205
dashboard link: https://syzkaller.appspot.com/bug?extid=cf4cf13056f85dec2c40
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
patch:          https://syzkaller.appspot.com/x/patch.diff?x=14add062f00000