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WARNING: CPU: 1 PID: 9537 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: 1 PID: 9537 Comm: syz-executor2 Not tainted 4.4.166+ #1
 0000000000000000 c402ed2c6b9a6083 ffff88008e467760 ffffffff81aa62ad
 ffffffff828353a0 ffff8801ba68c740 ffffffff82830900 0000000000000009
 00000000000003f9 ffff88008e467820 ffffffff813a2274 0000000041b58ab3
Call Trace:
 [<ffffffff81aa62ad>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aa62ad>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff813a2274>] panic+0x19e/0x359 kernel/panic.c:112
 [<ffffffff813a2464>] warn_slowpath_common.cold.6+0x20/0x20 kernel/panic.c:455
 [<ffffffff810d4489>] warn_slowpath_null+0x29/0x30 kernel/panic.c:492
 [<ffffffff810b79b4>] untrack_pfn+0x214/0x270 arch/x86/mm/pat.c:1017
 [<ffffffff8142ee73>] unmap_single_vma+0xea3/0x10d0 mm/memory.c:1322
 [<ffffffff814309f1>] unmap_vmas+0x81/0xd0 mm/memory.c:1373
 [<ffffffff8143ce8e>] unmap_region+0x1ae/0x300 mm/mmap.c:2499
 [<ffffffff8144103d>] do_munmap+0x80d/0xd40 mm/mmap.c:2696
 [<ffffffff8144c630>] move_vma+0x550/0x9a0 mm/mremap.c:334
 [<ffffffff8144d47a>] mremap_to mm/mremap.c:453 [inline]
 [<ffffffff8144d47a>] SYSC_mremap mm/mremap.c:516 [inline]
 [<ffffffff8144d47a>] SyS_mremap+0x9fa/0xd90 mm/mremap.c:483
 [<ffffffff82715ce1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
Kernel Offset: disabled
Rebooting in 86400 seconds..