linux-kernel - Re: [RFC PATCH 00/30] Code tagging framework and applications

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:   Thu, 1 Sep 2022 10:29:37 -0400
From:   Kent Overstreet <kent.overstreet@...ux.dev>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     Mel Gorman <mgorman@...e.de>,
        Suren Baghdasaryan <surenb@...gle.com>,
        akpm@...ux-foundation.org, mhocko@...e.com, vbabka@...e.cz,
        hannes@...xchg.org, roman.gushchin@...ux.dev, dave@...olabs.net,
        willy@...radead.org, liam.howlett@...cle.com, void@...ifault.com,
        juri.lelli@...hat.com, ldufour@...ux.ibm.com, peterx@...hat.com,
        david@...hat.com, axboe@...nel.dk, mcgrof@...nel.org,
        masahiroy@...nel.org, nathan@...nel.org, changbin.du@...el.com,
        ytcoode@...il.com, vincent.guittot@...aro.org,
        dietmar.eggemann@....com, rostedt@...dmis.org, bsegall@...gle.com,
        bristot@...hat.com, vschneid@...hat.com, cl@...ux.com,
        penberg@...nel.org, iamjoonsoo.kim@....com, 42.hyeyoo@...il.com,
        glider@...gle.com, elver@...gle.com, dvyukov@...gle.com,
        shakeelb@...gle.com, songmuchun@...edance.com, arnd@...db.de,
        jbaron@...mai.com, rientjes@...gle.com, minchan@...gle.com,
        kaleshsingh@...gle.com, kernel-team@...roid.com,
        linux-mm@...ck.org, iommu@...ts.linux.dev,
        kasan-dev@...glegroups.com, io-uring@...r.kernel.org,
        linux-arch@...r.kernel.org, xen-devel@...ts.xenproject.org,
        linux-bcache@...r.kernel.org, linux-modules@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH 00/30] Code tagging framework and applications

On Thu, Sep 01, 2022 at 09:00:17AM +0200, Peter Zijlstra wrote:
> On Wed, Aug 31, 2022 at 11:19:48AM +0100, Mel Gorman wrote:
> 
> > It's also unclear *who* would enable this. It looks like it would mostly
> > have value during the development stage of an embedded platform to track
> > kernel memory usage on a per-application basis in an environment where it
> > may be difficult to setup tracing and tracking. Would it ever be enabled
> > in production? 
> 
> Afaict this is developer only; it is all unconditional code.
> 
> > Would a distribution ever enable this? 
> 
> I would sincerely hope not. Because:
> 
> > If it's enabled, any overhead cannot be disabled/enabled at run or
> > boot time so anyone enabling this would carry the cost without never
> > necessarily consuming the data.
> 
> this.

We could make it a boot parameter, with the alternatives infrastructure - with a
bit of refactoring there'd be a single function call to nop out, and then we
could also drop the elf sections as well, so that when built in but disabled the
overhead would be practically nil.