Re: 4.17-rc1: early boot crash on x86_64 & pti

[Aaro Koskinen]

Hi,

On Tue, Apr 17, 2018 at 06:01:30PM +0300, Aaro Koskinen wrote:
> I'm getting early crash on x86_64 box with 4.17-rc1 and PTI
> enabled. Bisected to:
> 
> commit 39114b7a743e6759bab4d96b7d9651d44d17e3f9
> Author: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Date:   Fri Apr 6 13:55:17 2018 -0700
> 
>     x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image

[...]

> [    0.000000] Kernel/User page tables isolation: enabled
> [    0.000000] ------------[ cut here ]------------
> [    0.000000] CPA: called for zero pte. vaddr = ffffffff8d000000 cpa->vaddr = ffffffff8d000000
> [    0.000000] WARNING: CPU: 0 PID: 0 at arch/x86/mm/pageattr.c:1189 __cpa_process_fault+0x4d6/0x510

I started enabling more .config options, and it seems that enabling
CONFIG_XEN_PV does some magic to make booting work... But I shouldn't
need it.

A.