Re: [PATCH v2 0/2] Reset PCIe devices to address DMA problem on kdump with iommu

Takao Indoh
2012-10-03T01:02:43Z

(2012/10/03 4:37), Andi Kleen wrote:
> Takao Indoh <indou.takao@jp.fujitsu.com> writes:
>
>> These patches reset PCIe devices at boot time to address DMA problem on
>> kdump with iommu. When "reset_devices" is specified, a hot reset is
>> triggered on each PCIe root port and downstream port to reset its
>> downstream endpoint.
>
> Great. I've been pondering this for a long time, but you did finally
> implement it. I hope this will make kdump a lot more reliable at least
> on the systems that support per port reset.

Actually I got the idea of this patch from your comment below;-)
http://permalink.gmane.org/gmane.linux.network/162414

>
> Now the only question is: why make it a option and not default?

Except kdump I don't know the situation where this reset is useful, so I
introduced it as option so that it works only during kdump.

Thanks,
Takao Indoh