kernel panic: Proc-ful Page Fault in zthe Kernel at ADDR!

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 8dc899e19d0f vmm: x86: Set the reserved bits in rflags
git tree: https://github.com/akaros/akaros.git/master
console output: https://syzkaller.appspot.com/x/log.txt?x=122d932c400000
kernel config: https://syzkaller.appspot.com/x/.config?x=efef8cf2939304d3
dashboard link: https://syzkaller.appspot.com/bug?extid=14b8bfe3f1deda17cb44
compiler:

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+14b8bf...@syzkaller.appspotmail.com

Ukernel panic at kern/arch/x86/trap.c:312, from core 1: �Proc-ful Page
Fault in zthe Kernel at 0x0000000000000000!
�HW TRAP frame at 0�aWV�hxfffffff0000ca620 on core 1
� rax 0x0000000000000000
� rbx 0xffffffffc210f658
� rcx 0xffff800006d0c9d8
\ rdx 0x0000000000000001
�_t rbp 0xfffffff0000ca7w48
=rs]i r0xffffffffc
210f640
� rdi 0xffffffffc210f658
� r8 0x0000000000a000000
- r9 0xffff80000324e838
� r10 0x0000000000000168
� r11 0xffff80000324e708
� r12 0wx0000 �000000000000e
'8y?�r13 0xffffffffc20b1b��00
� � r14 0xffff{80000;�Y�324�e�7� 08
� r15 0xffffffffc210f640
h trap 0x0000000e Page Fault
u MFnm gs�*C �G��WGga;A�d�Bbs 0xffffffffc8667c40
� fsbs 0x0��000000000000000
� err 0x--------00000002
� rip 0xffffffffc20�0be1c
:_ cs 0x------------0008��| �U�
(n� G�p b flag 0x0000000000010086
m rsp 0xfffffff0000ca6e8
� ssK �(!�a�!2�
0x----------{( 3--0010
��/
��
�Backtrace of kernel context on Core 1:
5#01 [<0xffffffffc200beh1c>] in sem_down
�#d02
[<0xffffffffc2�YL�v��3��c$�c,����ҿ�9?��-�S᳝�� �@P }X~��� O~M 076054>]
in consread
#03 [<0xffffffffc207d4e2>] in mntversion at drivers/dev/mnt.c:223
#04 [<0xffffffffc207e882>] in mntattach at drivers/dev/mnt.c:356
#05 [<0xffffffffc203f221>] in sysmount at src/ns/sysfile.c:528
#06 [<0xffffffffc2055b11>] in sys_nmount at src/syscall.c:2259
#07 [<0xffffffffc2059409>] in syscall at src/syscall.c:2528
#08 [<0xffffffffc20595d4>] in run_local_syscall at src/syscall.c:2563
#09 [<0xffffffffc2059b09>] in prep_syscalls at src/syscall.c:2583
#10 [<0xffffffffc20ab36a>] in sysenter_callwrapper at arch/x86/trap.c:854


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.