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WARNING: CPU: 1 PID: 2085 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: 2085 Comm: syz-executor338 Not tainted 4.4.174+ #4
 0000000000000000 2349228cc06b04e7 ffff8800b6a6f7b8 ffffffff81aad1a1
 0000000000000000 ffffffff82835ee0 ffffffff82831440 00000000000003f9
 ffffffff810b6b24 ffff8800b6a6f898 ffffffff813a48c2 0000000041b58ab3
Call Trace:
 [<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff813a48c2>] panic+0x1b9/0x37b kernel/panic.c:112
 [<ffffffff813a4ab9>] warn_slowpath_common kernel/panic.c:455 [inline]
 [<ffffffff813a4ab9>] warn_slowpath_common.cold+0x20/0x20 kernel/panic.c:435
 [<ffffffff810d3aaa>] warn_slowpath_null+0x2a/0x30 kernel/panic.c:492
 [<ffffffff810b6b24>] untrack_pfn+0x214/0x270 arch/x86/mm/pat.c:1017
 [<ffffffff8143315e>] unmap_single_vma+0xe2e/0x1090 mm/memory.c:1322
 [<ffffffff81434d28>] unmap_vmas+0x48/0xa0 mm/memory.c:1373
 [<ffffffff81441689>] unmap_region+0x1a9/0x320 mm/mmap.c:2499
 [<ffffffff814455ba>] do_munmap+0x4ca/0xcf0 mm/mmap.c:2696
 [<ffffffff81450e2e>] move_vma+0x50e/0x920 mm/mremap.c:334
 [<ffffffff81451c1d>] mremap_to mm/mremap.c:453 [inline]
 [<ffffffff81451c1d>] SYSC_mremap mm/mremap.c:516 [inline]
 [<ffffffff81451c1d>] SyS_mremap+0x9dd/0xd60 mm/mremap.c:483
 [<ffffffff82718ba1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
Kernel Offset: disabled
Rebooting in 86400 seconds..