linux-kernel - Re: [PATCH v5 1/3] Provide in-kernel headers to make extending kernel easier

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: <20190411031540.ehezr6kq7ouobpzx@ast-mbp.dhcp.thefacebook.com>
Date:   Wed, 10 Apr 2019 20:15:42 -0700
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Olof Johansson <olof@...om.net>
Cc:     Joel Fernandes <joelaf@...gle.com>,
        Joel Fernandes <joel@...lfernandes.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Qais Yousef <qais.yousef@....com>,
        Dietmar Eggemann <dietmar.eggemann@....com>,
        Manoj Rao <linux@...ojrajarao.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Alexei Starovoitov <ast@...nel.org>,
        atish patra <atishp04@...il.com>,
        Daniel Colascione <dancol@...gle.com>,
        Dan Williams <dan.j.williams@...el.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Guenter Roeck <groeck@...omium.org>,
        Jonathan Corbet <corbet@....net>,
        Karim Yaghmour <karim.yaghmour@...rsys.com>,
        Kees Cook <keescook@...omium.org>,
        Android Kernel Team <kernel-team@...roid.com>,
        "open list:DOCUMENTATION" <linux-doc@...r.kernel.org>,
        "open list:KERNEL SELFTEST FRAMEWORK" 
        <linux-kselftest@...r.kernel.org>,
        linux-trace-devel@...r.kernel.org,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Randy Dunlap <rdunlap@...radead.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Shuah Khan <shuah@...nel.org>, Yonghong Song <yhs@...com>
Subject: Re: [PATCH v5 1/3] Provide in-kernel headers to make extending
 kernel easier

On Wed, Apr 10, 2019 at 09:34:49AM -0700, Olof Johansson wrote:
> On Wed, Apr 10, 2019 at 8:51 AM Joel Fernandes <joelaf@...gle.com> wrote:
> >
> > On Wed, Apr 10, 2019 at 11:07 AM Olof Johansson <olof@...om.net> wrote:
> > [snip]
> > > > > Wouldn't it be more convenient to provide it in a standardized format
> > > > > such that you won't have to take an additional step, and always have
> > > > > This is that form IMO.
...
> Compared to:
>  - Extract tarball
>  - Build and load
>  - Remove file tree from filesystem

I think there are too many assumptions in this thread in regard to what
is more convenient for user space.
I think bcc should try to avoid extracting tarball into file system.
For example libbcc can uncompress kheader.tar.xz into virtual file system
of clang front-end. It's more or less std::map<string, string>
with key=path, value=content of the file. Access to such in-memory
'files' is obviously faster than doing open/read syscalls.
bcc already uses this approach for some bcc internal 'files' that
it passes to clang during compilation.
All of /proc/kheaders.tar.xz files can be passed the same way
without extracting them into real file system.

Joel, would be great if you can share corresponding bcc patch
that takes advantage of /proc/kheaders