linux-kernel - Re: [PATCH 3/3] x86/static_call: Add support for Jcc tail-calls

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:   Tue, 24 Jan 2023 10:07:53 -0500
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     mingo@...nel.org, tglx@...utronix.de, bp@...en8.de,
        dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com,
        jpoimboe@...nel.org, jbaron@...mai.com, ardb@...nel.org,
        linux-kernel@...r.kernel.org, erhard_f@...lbox.org,
        ndesaulniers@...gle.com, mhiramat@...nel.org, sandipan.das@....com
Subject: Re: [PATCH 3/3] x86/static_call: Add support for Jcc tail-calls

On Tue, 24 Jan 2023 14:06:49 +0100
Peter Zijlstra <peterz@...radead.org> wrote:

> > Just to confirm, as it's not clear if this is the static call site or one
> > of the functions that is being called.  
> 
> Ah, you've not looked at enough asm then? ;-) Yes this is the static
> call site, see the __SCT_ target (instruction at 0x35d).

Yeah, could you specify it a bit more in the change log such that those
looking back at this don't have to have that requirement of staring at
enough asm ;-)

It's actually been some time since I stared at compiler output (although
now that I'm starting to play with rust, that's going to start back up
soon).

-- Steve