Re: [patch 0/4] x86: AMD microcode patch loading v2 fixes

From: Dmitry Adamushko
Date: Wed Jul 30 2008 - 05:57:36 EST


2008/7/30 Peter Oruba <peter.oruba@xxxxxxx>:
>> [ ... ]
>
> Since ucode updates may fix severe issues, it is supposed to happen as early
> as possible. If you re-plug your CPU into your socket, your BIOS also
> applies a ucode patch, but that won't necessarily be the latest and critical
> one.

Hum, let's say we don't do it from cpu-hotplug handlers [1] but from
start_secondary() before calling cpu_idle()? [*]

This way, we do it before any other task may have a chance to run on a
cpu which is not a case with cpu-hotplug handlers
(and we don't mess-up with cpu-hotplug events :-)

[ the drawback is that 'microcode' subsystem is not local to
microcode.c anymore ]

[1] if we need a sync. operation in cpu-hotplug handlers and IPI is
not ok (say, we need to run in a sleepablel context) then perhaps it's
workqueues + wait_on_cpu_work(). But then it's not a bit later than
could have been with [*].

heh, this issue has already popped up in another thread so it should
be fixed asap, imho.

Ingo, Peter? What would be the best way from your pov?


>
> Peter
>

--
Best regards,
Dmitry Adamushko
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