kernel BUG at mm/vmscan.c:LINE! (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    0d8b3265 Add linux-next specific files for 20190729
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1663c7d0600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ae96f3b8a7e885f7
dashboard link: https://syzkaller.appspot.com/bug?extid=8e6326965378936537c3
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=133c437c600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15645854600000

The bug was bisected to:

commit 06a833a1167e9cbb43a9a4317ec24585c6ec85cb
Author: Minchan Kim <minchan@xxxxxxxxxx>
Date:   Sat Jul 27 05:12:38 2019 +0000

    mm: introduce MADV_PAGEOUT

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1545f764600000
final crash:    https://syzkaller.appspot.com/x/report.txt?x=1745f764600000
console output: https://syzkaller.appspot.com/x/log.txt?x=1345f764600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+8e6326965378936537c3@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 06a833a1167e ("mm: introduce MADV_PAGEOUT")

raw: 01fffc0000090025 dead000000000100 dead000000000122 ffff88809c49f741
raw: 0000000000020000 0000000000000000 00000002ffffffff ffff88821b6eaac0
page dumped because: VM_BUG_ON_PAGE(PageActive(page))
page->mem_cgroup:ffff88821b6eaac0
------------[ cut here ]------------
kernel BUG at mm/vmscan.c:1156!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 9846 Comm: syz-executor110 Not tainted 5.3.0-rc2-next-20190729  
#54
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:shrink_page_list+0x2872/0x5430 mm/vmscan.c:1156
Code: d9 ea ff ff e8 df 3c dd ff 4c 8d 6b ff e9 1c db ff ff e8 d1 3c dd ff  
48 8b bd 10 ff ff ff 48 c7 c6 80 85 93 87 e8 fe 10 07 00 <0f> 0b e8 b7 3c  
dd ff be 08 00 00 00 4c 89 ef e8 0a f2 17 00 4c 89
RSP: 0018:ffff888092427598 EFLAGS: 00010293
RAX: ffff88809a6a43c0 RBX: 0000000000000020 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff819bfec7 RDI: ffffed1012484e97
RBP: ffff888092427730 R08: 0000000000000021 R09: ffffed1015d260d1
R10: ffffed1015d260d0 R11: ffff8880ae930687 R12: dffffc0000000000
R13: ffffea0002198000 R14: 0000000000000000 R15: ffffea0002198008
FS:  000055555617d880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000080 CR3: 00000000a818a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 reclaim_pages+0x3b8/0x8f0 mm/vmscan.c:2202
 madvise_cold_or_pageout_pte_range+0x18c4/0x2e20 mm/madvise.c:391
 walk_pmd_range mm/pagewalk.c:51 [inline]
 walk_pud_range mm/pagewalk.c:109 [inline]
 walk_p4d_range mm/pagewalk.c:135 [inline]
 walk_pgd_range mm/pagewalk.c:161 [inline]
 __walk_page_range+0xd2a/0x1680 mm/pagewalk.c:254
 walk_page_range+0x1a6/0x3e0 mm/pagewalk.c:335
 madvise_pageout_page_range.isra.0+0xdd/0x120 mm/madvise.c:532
 madvise_pageout+0x227/0x3a0 mm/madvise.c:568
 madvise_vma mm/madvise.c:965 [inline]
 __do_sys_madvise mm/madvise.c:1145 [inline]
 __se_sys_madvise mm/madvise.c:1073 [inline]
 __x64_sys_madvise+0x719/0x1500 mm/madvise.c:1073
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440149
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdb1a77db8 EFLAGS: 00000246 ORIG_RAX: 000000000000001c
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440149
RDX: 0000000000000015 RSI: 0000000000600003 RDI: 0000000020000000
RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004019d0
R13: 0000000000401a60 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace f888ef64246a2afc ]---
RIP: 0010:shrink_page_list+0x2872/0x5430 mm/vmscan.c:1156
Code: d9 ea ff ff e8 df 3c dd ff 4c 8d 6b ff e9 1c db ff ff e8 d1 3c dd ff  
48 8b bd 10 ff ff ff 48 c7 c6 80 85 93 87 e8 fe 10 07 00 <0f> 0b e8 b7 3c  
dd ff be 08 00 00 00 4c 89 ef e8 0a f2 17 00 4c 89
RSP: 0018:ffff888092427598 EFLAGS: 00010293
RAX: ffff88809a6a43c0 RBX: 0000000000000020 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff819bfec7 RDI: ffffed1012484e97
RBP: ffff888092427730 R08: 0000000000000021 R09: ffffed1015d260d1
R10: ffffed1015d260d0 R11: ffff8880ae930687 R12: dffffc0000000000
R13: ffffea0002198000 R14: 0000000000000000 R15: ffffea0002198008
FS:  000055555617d880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000080 CR3: 00000000a818a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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