general protection fault in page_remove_rmap

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 483d835c8189 Add linux-next specific files for 20180713
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=177d4b2c400000
kernel config: https://syzkaller.appspot.com/x/.config?x=60e5ac2478928314
dashboard link: https://syzkaller.appspot.com/bug?extid=12e30f90dab58d4f3edb
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
CC: [ak...@linux-foundation.org bornt...@de.ibm.com
jgl...@redhat.com khali...@oracle.com kirill....@linux.intel.com
linux-...@vger.kernel.org linu...@kvack.org mgo...@techsingularity.net
n-hor...@ah.jp.nec.com rp...@linux.vnet.ibm.com]

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+12e30f...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 1 PID: 974 Comm: syz-executor6 Not tainted 4.18.0-rc4-next-20180713+ #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:328 [inline]
RIP: 0010:PageHead include/linux/page-flags.h:500 [inline]
RIP: 0010:page_remove_file_rmap mm/rmap.c:1214 [inline]
RIP: 0010:page_remove_rmap+0xba5/0x1260 mm/rmap.c:1300
Code: f9 ff ff e8 ed 74 cb ff 4d 8d a7 48 37 00 00 e9 16 fd ff ff e8 dc 74
cb ff 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f
85 97 05 00 00 4c 8b 23 31 ff 49 c1 ec 0f 41 83 e4
RSP: 0000:ffff8801903bf300 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: ffffffff81b0f683
RDX: 1bffff8000000000 RSI: ffffffff81b0fb74 RDI: 0000000000000001
RBP: ffff8801903bf4f0 R08: ffff880196ef8480 R09: 0000000000000000
R10: ffffed0039706788 R11: ffff8801cb833c47 R12: ffff8801903bf580
R13: ffff8801cc3452f0 R14: ffff8801cc345318 R15: ffffffff81b5e2ac
FS: 0000000001b07940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4c9a2abd90 CR3: 00000001b3cfd000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
shrink_slab_memcg mm/vmscan.c:598 [inline]
shrink_slab+0x861/0xa60 mm/vmscan.c:671
shrink_node+0x429/0x16a0 mm/vmscan.c:2735
shrink_zones mm/vmscan.c:2964 [inline]
do_try_to_free_pages+0x3e7/0x1290 mm/vmscan.c:3026
try_to_free_mem_cgroup_pages+0x49d/0xc90 mm/vmscan.c:3324
reclaim_high.constprop.73+0x137/0x1e0 mm/memcontrol.c:2060
mem_cgroup_handle_over_high+0x8d/0x130 mm/memcontrol.c:2085
tracehook_notify_resume include/linux/tracehook.h:195 [inline]
exit_to_usermode_loop+0x287/0x380 arch/x86/entry/common.c:166
prepare_exit_to_usermode+0x342/0x3b0 arch/x86/entry/common.c:197
retint_user+0x8/0x18
RIP: 0033:0x40d7ef
Code: 0f 84 c8 02 00 00 48 83 bd 78 ff ff ff 00 0f 84 f9 04 00 00 48 8b 95
68 ff ff ff 44 89 95 38 ff ff ff 4c 8d ac 10 00 f7 ff ff <49> 89 85 90 06
00 00 49 8d 85 10 03 00 00 49 89 95 98 06 00 00 41
RSP: 002b:00007fff161d9e10 EFLAGS: 00010206
RAX: 00007f4c9a28b000 RBX: 0000000000020000 RCX: 0000000000455b0a
RDX: 0000000000021000 RSI: 0000000000021000 RDI: 0000000000000000
RBP: 00007fff161d9ef0 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff161d9f00
R13: 00007f4c9a2ab700 R14: 000000000072bf6c R15: 0000000000000001
Modules linked in:
Dumping ftrace buffer:
(ftrace buffer empty)
---[ end trace 7eb2a0c9a055ca2c ]---
RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:328 [inline]
RIP: 0010:PageHead include/linux/page-flags.h:500 [inline]
RIP: 0010:page_remove_file_rmap mm/rmap.c:1214 [inline]
RIP: 0010:page_remove_rmap+0xba5/0x1260 mm/rmap.c:1300
Code: f9 ff ff e8 ed 74 cb ff 4d 8d a7 48 37 00 00 e9 16 fd ff ff e8 dc 74
cb ff 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f
85 97 05 00 00 4c 8b 23 31 ff 49 c1 ec 0f 41 83 e4
RSP: 0000:ffff8801903bf300 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: ffffffff81b0f683
RDX: 1bffff8000000000 RSI: ffffffff81b0fb74 RDI: 0000000000000001
RBP: ffff8801903bf4f0 R08: ffff880196ef8480 R09: 0000000000000000
R10: ffffed0039706788 R11: ffff8801cb833c47 R12: ffff8801903bf580
R13: ffff8801cc3452f0 R14: ffff8801cc345318 R15: ffffffff81b5e2ac
FS: 0000000001b07940(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4c9a2abd90 CR3: 00000001b3cfd000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

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