Re: [PATCH 1/3 v4] x86/kdump: always reserve the low 1MiB when the crashkernel option is specified

From: Borislav Petkov
Date: Wed Oct 23 2019 - 03:43:24 EST


On Wed, Oct 23, 2019 at 01:23:33PM +0800, lijiang wrote:
> Kdump kernel will reuse the first 640k region because the real mode
> trampoline has to work in this area. When the vmcore is dumped, the
> old memory in this area may be accessed, therefore, kernel has to
> copy the contents of the first 640k area to a backup region so that
> kdump kernel can read the old memory from the backup area of the
> first 640k area, which is done in the purgatory().

That sounds better. :)

--
Regards/Gruss,
Boris.

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