linux-kernel - Re: [PATCH] cpufreq: set value of CPUFREQ_BOOST

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:	Fri, 28 Mar 2014 14:25:04 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	"Rafael J. Wysocki" <rjw@...ysocki.net>
Cc:	Lists linaro-kernel <linaro-kernel@...ts.linaro.org>,
	"cpufreq@...r.kernel.org" <cpufreq@...r.kernel.org>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	"Srivatsa S. Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>,
	"ego@...ux.vnet.ibm.com" <ego@...ux.vnet.ibm.com>,
	Vaidyanathan Srinivasan <svaidy@...ux.vnet.ibm.com>,
	Lukasz Majewski <l.majewski@...sung.com>,
	Viresh Kumar <viresh.kumar@...aro.org>
Subject: Re: [PATCH] cpufreq: set value of CPUFREQ_BOOST_FREQ to 0xABABABAB

On 24 March 2014 12:18, Viresh Kumar <viresh.kumar@...aro.org> wrote:
> Ideally, .driver_data field of struct cpufreq_frequency_table must not be used
> by core at all. But during a recent change if its value is same as
> CPUFREQ_BOOST_FREQ macro, then it is treated specially by core.
>
> The value of this macro was set to ~2 earlier, i.e. 0xFFFFFFFD. In case some
> driver is using this field for its own data and sets this field to -3, then with
> two's complement that value will also become 0xFFFFFFFD.
>
> To fix this issue, lets change value of this flag to a very uncommon value which
> shouldn't be used by any driver unless they want to use BOOST feature.
>
> Along with this update comments to make this more clear.
>
> Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
> ---

Please discard this patch now as I have sent a replacement patch.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/