linux-kernel - Re: [PATCH v2] perf tools: allow map files to specify DSO

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] [day] [month] [year] [list]

Message-ID: <20180508003416.GG4050@tassilo.jf.intel.com>
Date:   Mon, 7 May 2018 17:34:16 -0700
From:   Andi Kleen <ak@...ux.intel.com>
To:     Josh Hunt <johunt@...mai.com>
Cc:     mingo@...hat.com, acme@...nel.org, peterz@...radead.org,
        alexander.shishkin@...ux.intel.com, jolsa@...hat.com,
        namhyung@...nel.org, wangnan0@...wei.com,
        linux-perf-users@...r.kernel.org, linux-kernel@...r.kernel.org,
        eranian@...gle.com, kirill.shutemov@...ux.intel.com
Subject: Re: [PATCH v2] perf tools: allow map files to specify DSO

On Mon, May 07, 2018 at 02:30:32PM -0700, Josh Hunt wrote:
> On 05/07/2018 11:40 AM, Andi Kleen wrote:
> > On Mon, May 07, 2018 at 02:24:16PM -0400, Josh Hunt wrote:
> > > Add the ability to specify a DSO in the /tmp/perf-<PID>.map file.
> > > The DSO should be the first line in the file and readable by the
> > > running user. If a valid DSO is found all other contents of the
> > > file will be ignored. This allows things like callchain unwinding
> > > with DWARF to work.
> > 
> > FWIW it's ok, but also obsolete with Kirill's large-pages-in-tmpfs
> > work in newer kernels. With that you can just copy the executable into
> > a 2MB tmpfs and disable the manual huge page copying and everything
> > should work as usually.
> > 
> > So essentially it's only a hack for old kernels and old binaries.
> > 
> > But doesn't hurt I guess.
> 
> Ah, very interesting. I wasn't aware of this. Can you point me to some more
> details on this process?

See commit 5a6e75f8110c97e2a5488894d4e922187e6cb343

-Andi