Re: [PATCH][RFC] x86/microcode/intel: check cpu stepping and processor flag before saving microcode

From: Raj, Ashok
Date: Thu Nov 12 2020 - 16:54:47 EST


Hi ChenYu

I think you can drop the RFC tag.

I suppose you can add Cc stable as well. Boris should return next week to
take a look.


On Tue, Nov 10, 2020 at 09:52:47PM +0800, Chen Yu wrote:
> Currently scan_microcode() leverages microcode_matches() to check if the
> microcode matches the CPU by comparing the family and model. However before
> saving the microcode in scan_microcode(), the processor stepping and flag
> of the microcode signature should also be considered in order to avoid
> incompatible update and caused the failure of microcode update.
>
>
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=208535
> Fixes: 06b8534cb728 ("x86/microcode: Rework microcode loading")
> Suggested-by: "Raj, Ashok" <ashok.raj@xxxxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxxxx>
> Cc: Len Brown <len.brown@xxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> Cc: "Raj, Ashok" <ashok.raj@xxxxxxxxx>
> Cc: Tony Luck <tony.luck@xxxxxxxxx>
> Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
> --

Reviewed-by: Ashok Raj <ashok.raj@xxxxxxxxx>

Cheers,
Ashok