BUG: unable to handle kernel paging request in set_pfnblock_flags_mask

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b7a42146 Merge tag 'mips_fixes_5.1_1' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=115881a3200000
kernel config: https://syzkaller.appspot.com/x/.config?x=9a31fb246de2a622
dashboard link: https://syzkaller.appspot.com/bug?extid=ce068eed8bfb73c5f3d1
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [ak...@linux-foundation.org arya...@virtuozzo.com
iamjoon...@lge.com linux-...@vger.kernel.org linu...@kvack.org
mgo...@techsingularity.net mho...@suse.com vba...@suse.cz]

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+ce068e...@syzkaller.appspotmail.com

BUG: unable to handle kernel paging request at fffff10843ffe200
#PF error: [normal kernel read fault]
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 1050 Comm: khugepaged Not tainted 5.1.0-rc1+ #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__nr_to_section include/linux/mmzone.h:1165 [inline]
RIP: 0010:__pfn_to_section include/linux/mmzone.h:1238 [inline]
RIP: 0010:get_pageblock_bitmap mm/page_alloc.c:391 [inline]
RIP: 0010:set_pfnblock_flags_mask+0x6c/0x360 mm/page_alloc.c:468
Code: 35 a9 2c d0 08 48 85 f6 0f 84 c6 01 00 00 48 89 d7 48 c1 ef 16 48 8d
1c fe 48 be 00 00 00 00 00 fc ff df 48 89 df 48 c1 ef 03 <80> 3c 37 00 0f
85 8e 02 00 00 4c 8b 33 4d 85 f6 74 0a 83 e0 7f 48
RSP: 0018:ffff8880a82c70a8 EFLAGS: 00010a06
RAX: 0001fc0000000002 RBX: ffffa8421fff1000 RCX: 0000000000000003
RDX: fe00000000014200 RSI: dffffc0000000000 RDI: 1ffff50843ffe200
RBP: ffff8880a82c70f8 R08: 0000000000000001 R09: ffffed1015d25bc8
R10: ffffed1015d25bc7 R11: ffff8880ae92de3b R12: 0000000000000001
R13: 0000000000000001 R14: ffff8880a82c7550 R15: 7fffea0000508000
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff10843ffe200 CR3: 00000000901e9000 CR4: 00000000001406e0
Call Trace:
fast_isolate_around mm/compaction.c:1240 [inline]
fast_isolate_freepages mm/compaction.c:1411 [inline]
isolate_freepages mm/compaction.c:1431 [inline]
compaction_alloc+0x1b02/0x2290 mm/compaction.c:1543
unmap_and_move mm/migrate.c:1175 [inline]
migrate_pages+0x484/0x2cd0 mm/migrate.c:1426
compact_zone+0x1b56/0x38d0 mm/compaction.c:2174
compact_zone_order+0x1af/0x2a0 mm/compaction.c:2299
try_to_compact_pages+0x268/0xaf0 mm/compaction.c:2351
__alloc_pages_direct_compact+0x154/0x4d0 mm/page_alloc.c:3770
__alloc_pages_slowpath+0xb14/0x28b0 mm/page_alloc.c:4414
__alloc_pages_nodemask+0x57e/0x7e0 mm/page_alloc.c:4622
__alloc_pages include/linux/gfp.h:473 [inline]
__alloc_pages_node include/linux/gfp.h:486 [inline]
khugepaged_alloc_page+0x96/0x160 mm/khugepaged.c:773
collapse_huge_page+0x130/0x3f60 mm/khugepaged.c:962
khugepaged_scan_pmd mm/khugepaged.c:1215 [inline]
khugepaged_scan_mm_slot mm/khugepaged.c:1725 [inline]
khugepaged_do_scan mm/khugepaged.c:1806 [inline]
khugepaged+0x28c3/0x3f40 mm/khugepaged.c:1851
kthread+0x357/0x430 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: fffff10843ffe200
---[ end trace 5465243b0014feb9 ]---
RIP: 0010:__nr_to_section include/linux/mmzone.h:1165 [inline]
RIP: 0010:__pfn_to_section include/linux/mmzone.h:1238 [inline]
RIP: 0010:get_pageblock_bitmap mm/page_alloc.c:391 [inline]
RIP: 0010:set_pfnblock_flags_mask+0x6c/0x360 mm/page_alloc.c:468
Code: 35 a9 2c d0 08 48 85 f6 0f 84 c6 01 00 00 48 89 d7 48 c1 ef 16 48 8d
1c fe 48 be 00 00 00 00 00 fc ff df 48 89 df 48 c1 ef 03 <80> 3c 37 00 0f
85 8e 02 00 00 4c 8b 33 4d 85 f6 74 0a 83 e0 7f 48
RSP: 0018:ffff8880a82c70a8 EFLAGS: 00010a06
RAX: 0001fc0000000002 RBX: ffffa8421fff1000 RCX: 0000000000000003
RDX: fe00000000014200 RSI: dffffc0000000000 RDI: 1ffff50843ffe200
RBP: ffff8880a82c70f8 R08: 0000000000000001 R09: ffffed1015d25bc8
R10: ffffed1015d25bc7 R11: ffff8880ae92de3b R12: 0000000000000001
R13: 0000000000000001 R14: ffff8880a82c7550 R15: 7fffea0000508000
FS: 0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff10843ffe200 CR3: 00000000901e9000 CR4: 00000000001406e0


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.