Re: commit 3c2e7f7de3 (KVM use NPT page attributes) causes boot failures

[Xiao Guangrong]

On 09/01/2015 09:56 PM, Markus Trippelsdorf wrote:
> On 2015.09.01 at 21:00 +0800, Xiao Guangrong wrote:
> > Did it trigger the BUG()/BUG_ON() in mtrr2protval()/fallback_mtrr_type()?
> > If yes, could you please print the actual value out?
>
> It is the BUG() in fallback_mtrr_type(). I changed it to a printk and
> it prints 1 for the value of mtrr.
>
>   MTRR_TYPE_WRCOMB     1

Then I suspect pat is not enabled in your box, could you please check
CONFIG_X86_PAT is selected in your .config file, pat is shown in
/proc/cpuid, "nopat" kernel parameter is used, and dmesg | grep PAT.

I will post a fix if the suspect is right.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/