linux-kernel - Re: [PATCH] x86/alternative: Support relocations in alternatives

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 8 Feb 2023 09:58:53 +0100
From:   Peter Zijlstra <peterz@...radead.org>
To:     "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
Cc:     x86@...nel.org, Borislav Petkov <bp@...en8.de>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Andrew Cooper <Andrew.Cooper3@...rix.com>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] x86/alternative: Support relocations in alternatives

On Tue, Feb 07, 2023 at 05:05:27PM +0100, Peter Zijlstra wrote:

> Also, Masami, how difficuly would it be to do insn_is_nop() that matches
> most/all conventional NOP instructions?

Just looked at that, while NOP and NOPL are relatively easy to do, the
32bit NOPs are a pain to decode since they're actual instructions with
the side-effect of not actually doing anything, like 'mov %reg,%reg' and
'lea (%reg),%reg'. Esp. that latter is popular since it has all the
various displacement encodings to grow it into a very long instruction.

I'll put it on the todo list I suppose, not something for now.