linux-kernel - [RFC][PATCH 0/8] jump_label, x86: Support variable sized JMP instructions

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-next>] [day] [month] [year] [list]

Message-Id: <20190628102113.360432762@infradead.org>
Date:   Fri, 28 Jun 2019 12:21:13 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     x86@...nel.org, peterz@...radead.org, linux-kernel@...r.kernel.org
Cc:     Josh Poimboeuf <jpoimboe@...hat.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Daniel Bristot de Oliveira <bristot@...hat.com>,
        Jason Baron <jbaron@...mai.com>, Nadav Amit <namit@...are.com>,
        Andy Lutomirski <luto@...nel.org>,
        Eugeniy Paltsev <Eugeniy.Paltsev@...opsys.com>,
        Vineet Gupta <Vineet.Gupta1@...opsys.com>
Subject: [RFC][PATCH 0/8] jump_label, x86: Support variable sized JMP instructions

After discussing jump_labels with Eugeny and Vineet the other day, I started
playing with adding support for our 2 byte JMP/8 instruction. Much thanks to
Josh for (re)discovering the .skip trick.

These patches boot an x86_64 defconfig in kvm, so it must be perfect.

Using the 2 byte jumps saves about ~6k text for an x86_64-defconfig build.