linux-kernel - Re: [PATCH V2 2/3] sched: Fix race in idle

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:	Thu, 13 Feb 2014 15:40:00 +0530
From:	Preeti U Murthy <preeti@...ux.vnet.ibm.com>
To:	Alex Shi <alex.shi@...aro.org>
CC:	Daniel Lezcano <daniel.lezcano@...aro.org>,
	Preeti Murthy <preeti.lkml@...il.com>,
	Peter Zijlstra <peterz@...radead.org>, mingo@...nel.org,
	LKML <linux-kernel@...r.kernel.org>,
	Lists linaro-kernel <linaro-kernel@...ts.linaro.org>
Subject: Re: [PATCH V2 2/3] sched: Fix race in idle_balance()

Hi,

On 02/13/2014 01:15 PM, Alex Shi wrote:
> On 02/11/2014 07:11 PM, Daniel Lezcano wrote:
>> On 02/10/2014 10:24 AM, Preeti Murthy wrote:
>>> HI Daniel,
>>>
>>> Isn't the only scenario where another cpu can put an idle task on
>>> our runqueue,
>>
>> Well, I am not sure to understand what you meant, but I assume you are
>> asking if it is possible to have a task to be pulled when we are idle,
>> right ?
>>
>> This patch fixes the race when the current cpu is *about* to enter idle
>> when calling schedule().
> 
> Preeti said the she didn't see a possible to insert a task on the cpu.
> 
> I also did a quick check, maybe task come from wakeup path?

Yes this is possible. Thanks for pointing this :)

Reviewed-by: Preeti U Murthy <preeti@...ux.vnet.ibm.com>
> 

--
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/