kernel panic: Proc-ful Page Fault in th+e+ Kernel at 0x000K0E< 'pk$,2,Hbali3*jADDR!.G[

[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=16b5408c400000
kernel config: https://syzkaller.appspot.com/x/.config?x=efef8cf2939304d3
dashboard link: https://syzkaller.appspot.com/bug?extid=f8e1dfbc1f87f8e7c70a
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+f8e1df...@syzkaller.appspotmail.com

kernel panic at kern/arch/x86/trap.c:312, from core 1: Proc-ful Page Fault
in th+e+ Kernel at
0x000K�0E< 'p k�$�,2�, Hb�� al �i3*�j ��00000000001b!.G��㨪[
�HW TRAP frame at 0xfffffff0000a3d30 on core 1
rax 0x0000000000000000
��?���u� rbx 0x05� k�� /ff��� ^�eb� x������*ff8000069b4820
d rcx �0xfff�ffff0000a3ea0
� rdx 0xfffffff0000a3d6c
b �r�bp 0xfffffff0000�a3�e38
� r A3$�I��si 0x000000B�00000~00000
/��"^ rdi 0xfffffff800�#000a3ea0
r8 0x0000000000000001
r9 0xffffffffc8790880
r10 0x0000000000000030
r11 0xffff800015799ea0
r12 0xffff800015b18b80
r13 0x0000000020000540
r14 0x0000000000000073
r15 0x00000000000000c7
trap 0x0000000e Page Fault
gsbs 0xffffffffc8667c40
fsbs 0x0000000000000000
err 0x--------00000000
rip 0xffffffffc20583f4
cs 0x------------0008
flag 0x0000000000010246
rsp 0xfffffff0000a3df8
ss 0x------------0010
Backtrace of kernel context on Core 1:
#01 [<0xffffffffc20583f4>] in sys_readlink at src/syscall.c:2037
#02 [<0xffffffffc2059409>] in syscall at src/syscall.c:2528
#03 [<0xffffffffc20595d4>] in run_local_syscall at src/syscall.c:2563
#04 [<0xffffffffc2059b09>] in prep_syscalls at src/syscall.c:2583
#05 [<0xffffffffc20ab36a>] in sysenter_callwrapper at arch/x86/trap.c:854
[kernel] Vcoreid -1 unsafe! (too big?)


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[syzbot]

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