------------[ cut here ]------------
WARNING: CPU: 0 PID: 7967 at arch/x86/mm/pat.c:1017 untrack_pfn+0x214/0x270 arch/x86/mm/pat.c:1017()
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7967 Comm: syz-executor2 Not tainted 4.4.169+ #7
 0000000000000000 3f13a0d69fb8f5a4 ffff8801d0867590 ffffffff81aa635d
 ffffffff828353a0 ffff8800b46b97c0 ffffffff82830900 0000000000000009
 00000000000003f9 ffff8801d0867650 ffffffff813a22b4 0000000041b58ab3
Call Trace:
 [<ffffffff81aa635d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aa635d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff813a22b4>] panic+0x19e/0x359 kernel/panic.c:112
 [<ffffffff813a24a4>] warn_slowpath_common.cold.6+0x20/0x20 kernel/panic.c:455
 [<ffffffff810d44d9>] warn_slowpath_null+0x29/0x30 kernel/panic.c:492
 [<ffffffff810b7a04>] untrack_pfn+0x214/0x270 arch/x86/mm/pat.c:1017
 [<ffffffff8142ee93>] unmap_single_vma+0xea3/0x10d0 mm/memory.c:1322
 [<ffffffff81430a11>] unmap_vmas+0x81/0xd0 mm/memory.c:1373
 [<ffffffff814476d4>] exit_mmap+0x1d4/0x390 mm/mmap.c:2961
 [<ffffffff810cadc6>] __mmput kernel/fork.c:717 [inline]
 [<ffffffff810cadc6>] mmput+0xd6/0x350 kernel/fork.c:737
 [<ffffffff810d95dd>] exit_mm kernel/exit.c:440 [inline]
 [<ffffffff810d95dd>] do_exit+0x9ed/0x2ce0 kernel/exit.c:742
 [<ffffffff810dfb31>] do_group_exit+0x111/0x300 kernel/exit.c:885
 [<ffffffff811013ec>] get_signal+0x4ec/0x14a0 kernel/signal.c:2321
 [<ffffffff8100bdc5>] do_signal+0x95/0x1840 arch/x86/kernel/signal.c:712
 [<ffffffff81003eba>] exit_to_usermode_loop+0x11a/0x160 arch/x86/entry/common.c:184
 [<ffffffff81005784>] prepare_exit_to_usermode arch/x86/entry/common.c:221 [inline]
 [<ffffffff81005784>] syscall_return_slowpath+0x254/0x2d0 arch/x86/entry/common.c:286
 [<ffffffff82716421>] int_ret_from_sys_call+0x25/0xa3
Kernel Offset: disabled
Rebooting in 86400 seconds..