general protection fault in page_vma_mapped_walk

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4938296e03bd Linux 4.19.198
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13edd338300000
kernel config: https://syzkaller.appspot.com/x/.config?x=9013c716691ad1fe
dashboard link: https://syzkaller.appspot.com/bug?extid=fa151651c4146a3ba664
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fa1516...@syzkaller.appspotmail.com

ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
Bluetooth: hci4: command 0x0409 tx timeout
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 13055 Comm: kworker/u4:0 Not tainted 4.19.198-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:page_vma_mapped_walk+0x86a/0x27d0 mm/page_vma_mapped.c:196
Code: 8b 44 24 08 80 38 00 0f 85 58 1a 00 00 48 8b 44 24 20 4c 89 f5 48 c1 ed 24 81 e5 f8 0f 00 00 48 03 68 50 48 89 e8 48 c1 e8 03 <42> 80 3c 38 00 0f 85 3e 19 00 00 4c 8b 65 00 31 ff 44 89 e5 83 e5
RSP: 0018:ffff88823ac0eeb8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88823ac0efa0 RCX: ffffffff818f2a67
RDX: 0000000000000000 RSI: ffffffff818f2b8f RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 000000004a5c62ec R12: 0000000000000000
R13: 0000000000000001 R14: 0000001b2e322000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b98b5378e0 CR3: 000000009c0f4000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
page_mkclean_one+0x3af/0x860 mm/rmap.c:899
rmap_walk_file+0x539/0xb10 mm/rmap.c:1897
rmap_walk+0x105/0x190 mm/rmap.c:1915
page_mkclean+0x20f/0x2b0 mm/rmap.c:981
clear_page_dirty_for_io+0x305/0xee0 mm/page-writeback.c:2687
mpage_submit_page+0x80/0x250 fs/ext4/inode.c:2215
mpage_process_page_bufs+0x534/0x630 fs/ext4/inode.c:2345
mpage_prepare_extent_to_map+0x9a2/0xf10 fs/ext4/inode.c:2707
ext4_writepages+0x111d/0x37f0 fs/ext4/inode.c:2835
do_writepages+0xe5/0x290 mm/page-writeback.c:2344
__writeback_single_inode+0x10c/0x11d0 fs/fs-writeback.c:1385
writeback_sb_inodes+0x537/0xef0 fs/fs-writeback.c:1647
__writeback_inodes_wb+0xc6/0x280 fs/fs-writeback.c:1716
wb_writeback+0x841/0xcc0 fs/fs-writeback.c:1822
wb_check_old_data_flush fs/fs-writeback.c:1924 [inline]
wb_do_writeback fs/fs-writeback.c:1977 [inline]
wb_workfn+0x92b/0x1350 fs/fs-writeback.c:2006
process_one_work+0x864/0x1570 kernel/workqueue.c:2153
worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
kthread+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace 21c3892683b722bb ]---
RIP: 0010:page_vma_mapped_walk+0x86a/0x27d0 mm/page_vma_mapped.c:196
Code: 8b 44 24 08 80 38 00 0f 85 58 1a 00 00 48 8b 44 24 20 4c 89 f5 48 c1 ed 24 81 e5 f8 0f 00 00 48 03 68 50 48 89 e8 48 c1 e8 03 <42> 80 3c 38 00 0f 85 3e 19 00 00 4c 8b 65 00 31 ff 44 89 e5 83 e5
RSP: 0018:ffff88823ac0eeb8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88823ac0efa0 RCX: ffffffff818f2a67
RDX: 0000000000000000 RSI: ffffffff818f2b8f RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 000000004a5c62ec R12: 0000000000000000
R13: 0000000000000001 R14: 0000001b2e322000 R15: dffffc0000000000
Bluetooth: hci4: command 0x041b tx timeout
FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b98b5378e0 CR3: 000000009c0f4000 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.