linux-kernel - Re: [PATCH 1/2] cpufreq: Add governor operation ongoing flag

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: <CAFgnuDe1VwH2_xyyRN382=gGO8N6QKONKpGkLBGK8Hv2Zh1orA@mail.gmail.com>
Date:	Wed, 14 Aug 2013 16:50:39 +0800
From:	Xiaoguang Chen <chenxg.marvell@...il.com>
To:	Viresh Kumar <viresh.kumar@...aro.org>
Cc:	Xiaoguang Chen <chenxg@...vell.com>,
	"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>,
	"Rafael J. Wysocki" <rjw@...k.pl>
Subject: Re: [PATCH 1/2] cpufreq: Add governor operation ongoing flag

2013/8/14 Viresh Kumar <viresh.kumar@...aro.org>:
> On 14 August 2013 13:49, Xiaoguang Chen <chenxg.marvell@...il.com> wrote:
>> Yes, "START (If STOP passed)", this is important,  we don't have this
>> patch on our code base, So even Process B's STOP failed(as governor
>> enable flag is set to false by process A already ), it can still do
>> START operation, So my problem occurs.
>> My problem is that I see ondemand governor is started twice during
>> frequent governor switch and cpu hotplug stress test.
>>
>> The After seeing your patch for the return value checking, I think my
>> problem should not occur.
>> This issue really botherred me for a long time. :(
>
> Exactly, the problem was users of this API were abusing it as they didn't
> cared for its return value. I hope that is fixed widely now and in case
> some places are still left, they should be fixed as well.
>
> --
> viresh


Hi, Viresh
After checking your patch, I find that __cpufreq_set_policy function
doesn't check STOP and EXIT 's return value
is it on purpose? if not, I can provide a patch to add it.

Thanks
Xiaoguang
--
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/