linux-kernel - Re: [PATCH v3 3/5] OPP: Improve require-opps linking

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: <20190723102842.t2s45zzylsjuccm4@vireshk-i7>
Date:   Tue, 23 Jul 2019 15:58:42 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Saravana Kannan <saravanak@...gle.com>
Cc:     MyungJoo Ham <myungjoo.ham@...sung.com>,
        Kyungmin Park <kyungmin.park@...sung.com>,
        Chanwoo Choi <cw00.choi@...sung.com>,
        Viresh Kumar <vireshk@...nel.org>, Nishanth Menon <nm@...com>,
        Stephen Boyd <sboyd@...nel.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Sibi Sankar <sibis@...eaurora.org>, kernel-team@...roid.com,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 3/5] OPP: Improve require-opps linking

$subject doesn't have correct property name.

On 17-07-19, 15:23, Saravana Kannan wrote:
> Currently, the linking of required-opps fails silently if the
> destination OPP table hasn't been added before the source OPP table is
> added. This puts an unnecessary requirement that the destination table
> be added before the source table is added.
> 
> In reality, the destination table is needed only when we try to
> translate from source OPP to destination OPP. So, instead of
> completely failing, retry linking the tables when the translation is
> attempted.
> 
> Signed-off-by: Saravana Kannan <saravanak@...gle.com>
> ---
>  drivers/opp/core.c | 32 +++++++++++-----
>  drivers/opp/of.c   | 91 ++++++++++++++++++++++------------------------
>  drivers/opp/opp.h  |  5 +++
>  3 files changed, 71 insertions(+), 57 deletions(-)

Here is the general feedback and requirements I have:

- We shouldn't do it from _set_required_opps() but way earlier, it
  shouldn't affect the fast path (where we change the frequency).

- Programming required-opps for half of the properties isn't correct,
  i.e. in case only few of the required-opps are parsed until now. So
  setting of rate shouldn't even start unless the OPP table is fully
  initialized with all required-opps in it.

-- 
viresh