linux-kernel - Re: [RFC PATCH 0/2] improve vmalloc allocation

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: <20181023072306.GN18839@dhcp22.suse.cz>
Date:   Tue, 23 Oct 2018 09:23:06 +0200
From:   Michal Hocko <mhocko@...nel.org>
To:     Uladzislau Rezki <urezki@...il.com>, Shuah Khan <shuah@...nel.org>
Cc:     Matthew Wilcox <willy@...radead.org>,
        Andrew Morton <akpm@...ux-foundation.org>, linux-mm@...ck.org,
        LKML <linux-kernel@...r.kernel.org>,
        Thomas Garnier <thgarnie@...gle.com>,
        Oleksiy Avramchenko <oleksiy.avramchenko@...ymobile.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Joel Fernandes <joelaf@...gle.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...e.hu>, Tejun Heo <tj@...nel.org>
Subject: Re: [RFC PATCH 0/2] improve vmalloc allocation

Hi Shuah,

On Mon 22-10-18 18:52:53, Uladzislau Rezki wrote:
> On Mon, Oct 22, 2018 at 02:51:42PM +0200, Michal Hocko wrote:
> > Hi,
> > I haven't read through the implementation yet but I have say that I
> > really love this cover letter. It is clear on intetion, it covers design
> > from high level enough to start discussion and provides a very nice
> > testing coverage. Nice work!
> > 
> > I also think that we need a better performing vmalloc implementation
> > long term because of the increasing number of kvmalloc users.
> > 
> > I just have two mostly workflow specific comments.
> > 
> > > A test-suite patch you can find here, it is based on 4.18 kernel.
> > > ftp://vps418301.ovh.net/incoming/0001-mm-vmalloc-stress-test-suite-v4.18.patch
> > 
> > Can you fit this stress test into the standard self test machinery?
> > 
> If you mean "tools/testing/selftests", then i can fit that as a kernel module.
> But not all the tests i can trigger from kernel module, because 3 of 8 tests
> use __vmalloc_node_range() function that is not marked as EXPORT_SYMBOL.

Is there any way to conditionally export these internal symbols just for
kselftests? Or is there any other standard way how to test internal
functionality that is not exported to modules?
-- 
Michal Hocko
SUSE Labs