Hello,

syzkaller hit the following crash on  
37759fa6d0fa9e4d6036d19ac12f555bfc0aeafd
git://git.cmpxchg.org/linux-mmots.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers


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Reported-by: syzbot+1d7d9ce4ce4a23cb7d3b@syzkaller.appspotmail.com
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WARNING: CPU: 0 PID: 3192 at ./arch/x86/include/asm/fpu/internal.h:340  
paravirt_write_msr arch/x86/include/asm/paravirt.h:21 [inline]
WARNING: CPU: 0 PID: 3192 at ./arch/x86/include/asm/fpu/internal.h:340  
wrmsrl arch/x86/include/asm/paravirt.h:149 [inline]
WARNING: CPU: 0 PID: 3192 at ./arch/x86/include/asm/fpu/internal.h:340  
load_seg_legacy arch/x86/kernel/process_64.c:255 [inline]
WARNING: CPU: 0 PID: 3192 at ./arch/x86/include/asm/fpu/internal.h:340  
__switch_to+0x10bd/0x13c0 arch/x86/kernel/process_64.c:455
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3192 Comm: syzkaller835319 Not tainted 4.15.0-rc4-mm1+ #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
Shutting down cpus with NMI
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user [me m   
or41y .3ac65ce0s98s
]
Rebooting in 86400 seconds..
---[ end trace 2d2aa5997809e25d ]---


---
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