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Subject: RE: [PATCH] x86: Use low memory size directly from Multiboot
Date: Wed, 9 Feb 2022 12:46:07 +0100
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> The comment here is a pretty clear indication that bad values may have =
been
> observed, even if this was only in the distant past. But we have to =
not
> regress even on very old boot loaders.
>=20
> Is the kexec case recognizable by any means (including to distinguish =
kexec
> properly communicating the value vs it not doing so, as iirc it was =
said on irc
> that this didn't always work correctly there), such that we could skip =
using
> the BDA value in that case?

Old Kexec used to report the value in bytes instead of kilobytes like =
it's supposed to. I can make a special case for that so that we won't =
have to rely on the BDA.