Re: [PATCH] x86-64: disable the GART before allocate aperture

Yinghai Lu
2007-06-22T19:48:27Z

Muli Ben-Yehuda wrote:
> On Fri, Jun 22, 2007 at 12:19:15PM -0700, Yinghai Lu wrote:
>> [PATCH] x86-64: disable the GART before allocate aperture
>>
>> For K8 system: 4G RAM with memory hole remapping enabled, or more
>> than 4G RAM installed. when mem is allocated for GART, it will do
>> the memset for clear. and for kexec case, the first kernel already
>> enable that, the memset in second kernel will cause the system
>> restart. So disable that at first before we try to allocate mem for
>> it.
>
> Why does the memset in the second kernel cause a system restart?
>
GART is enabled by first kernel, and some driver is using that for DMA.

YH