Re: [PATCH 0/2 RESEND v7] add reserved e820 ranges to the kdump kernel e820 table

From: Borislav Petkov
Date: Mon Nov 26 2018 - 13:05:06 EST

On Mon, Nov 26, 2018 at 09:44:46AM -0800, Dave Hansen wrote:
> On 11/23/18 9:12 PM, Lianbo Jiang wrote:
> > These patches add the new I/O resource descriptor 'IORES_DESC_RESERVED'
> > for the iomem resources search interfaces, and in order to make it still
> > work after the new descriptor is added, these codes originally related
> > to 'IORES_DESC_NONE' have been updated.
> I'm having a really hard time figuring out what problem these patches solve.
> What end-user visible behavior does this set change?

Yeah, that was a long process of digging out the "why".

I'd recommend reading the previous threads and, more specifically:

in short: we need to export e820 reserved ranges to the second kernel so
that it can talk to PCI devices properly. (And I'm wondering how it did
work until now...)


Good mailing practices for 400: avoid top-posting and trim the reply.