linux-kernel - Re: [PATCH 08/15] x86/alternatives: Teach text_poke

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]

Message-ID: <20190611115210.490c345a@gandalf.local.home>
Date:   Tue, 11 Jun 2019 11:52:10 -0400
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     Andy Lutomirski <luto@...capital.net>,
        Masami Hiramatsu <mhiramat@...nel.org>, x86@...nel.org,
        linux-kernel@...r.kernel.org,
        Ard Biesheuvel <ard.biesheuvel@...aro.org>,
        Andy Lutomirski <luto@...nel.org>,
        Ingo Molnar <mingo@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Jason Baron <jbaron@...mai.com>, Jiri Kosina <jkosina@...e.cz>,
        David Laight <David.Laight@...lab.com>,
        Borislav Petkov <bp@...en8.de>,
        Julia Cartwright <julia@...com>, Jessica Yu <jeyu@...nel.org>,
        "H. Peter Anvin" <hpa@...or.com>, Nadav Amit <namit@...are.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Edward Cree <ecree@...arflare.com>,
        Daniel Bristot de Oliveira <bristot@...hat.com>
Subject: Re: [PATCH 08/15] x86/alternatives: Teach text_poke_bp() to emulate
 instructions

On Tue, 11 Jun 2019 11:22:54 -0400
Steven Rostedt <rostedt@...dmis.org> wrote:

> What would work would be to:
> 
> 	add breakpoint to first opcode.
> 
> 	call synchronize_tasks();

BTW, that should be "synchronize_rcu_tasks()"

-- Steve

> 
> 	/* All tasks now hitting breakpoint and jumping over affected
> 	code */
> 
> 	update the rest of the instructions.
> 
> 	replace breakpoint with jmp.