From: Borislav Petkov <bp@alien8.de>
To: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
Cc: Ingo Molnar <mingo@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
"H. Peter Anvin" <hpa@zytor.com>,
x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] x86/microcode/AMD: check microcode file sanity before loading it
Date: Mon, 12 Mar 2018 14:06:53 +0100 [thread overview]
Message-ID: <20180312130653.GC9431@pd.tnic> (raw)
In-Reply-To: <ddf0ddc2-bc46-d61c-7080-0eca26d6bfcf@maciej.szmigiero.name>
On Mon, Mar 12, 2018 at 01:56:59PM +0100, Maciej S. Szmigiero wrote:
> The equivalent CPU table is allocated using vmalloc() so it is nice
> when the maximum size is an integer multiple of the page size.
Arbitrary.
> Since the maximum entry count in current microcode files is 18 the
Where did you dream up that 18?
> maximum size of 256 entries (or one page) gives us plenty of headroom.
Arbitrary.
> Also, looking in the past, there probably won't be more than 256 AMD CPU
> types in one CPU family.
Wrong.
The only limitation on the equivalence table size we have is the 32-bit
unsigned length field at offset 8 in the equivalence table header.
> This limit is an absolute upper cap of a patch size.
More dreamt up crap.
See verify_patch_size() for the actual patch sizes.
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
next prev parent reply other threads:[~2018-03-12 13:07 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-11 15:27 [PATCH v2] x86/microcode/AMD: check microcode file sanity before loading it Maciej S. Szmigiero
2018-03-12 9:53 ` Borislav Petkov
2018-03-12 12:56 ` Maciej S. Szmigiero
2018-03-12 13:06 ` Borislav Petkov [this message]
2018-03-12 13:32 ` Maciej S. Szmigiero
2018-03-12 13:48 ` Borislav Petkov
2018-03-12 14:10 ` Maciej S. Szmigiero
2018-03-12 14:30 ` Borislav Petkov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180312130653.GC9431@pd.tnic \
--to=bp@alien8.de \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mail@maciej.szmigiero.name \
--cc=mingo@redhat.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox