linux-kernel - Re: [PATCH v2 0/5] arm-cci400: PMU monitoring support on ARM64

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: <54F6F7E3.40302@arm.com>
Date:	Wed, 04 Mar 2015 12:17:39 +0000
From:	"Suzuki K. Poulose" <Suzuki.Poulose@....com>
To:	Sudeep Holla <Sudeep.Holla@....com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
CC:	"nico@...aro.org" <nico@...aro.org>,
	"b.zolnierkie@...sung.com" <b.zolnierkie@...sung.com>,
	"kgene@...nel.org" <kgene@...nel.org>,
	"a.kesavan@...sung.com" <a.kesavan@...sung.com>,
	"arnd@...db.de" <arnd@...db.de>,
	"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Liviu Dudau <Liviu.Dudau@....com>,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@....com>,
	Pawel Moll <Pawel.Moll@....com>,
	"olof@...om.net" <olof@...om.net>,
	Punit Agrawal <Punit.Agrawal@....com>,
	Will Deacon <Will.Deacon@....com>,
	Catalin Marinas <Catalin.Marinas@....com>
Subject: Re: [PATCH v2 0/5] arm-cci400: PMU monitoring support on ARM64

On 03/03/15 16:00, Sudeep Holla wrote:
>
>
> On 02/03/15 11:29, Suzuki K. Poulose wrote:
>> From: "Suzuki K. Poulose" <suzuki.poulose@....com>
>>
>> This series enables the PMU monitoring support for CCI400 on ARM64.
>> The existing CCI400 driver code is a mix of PMU driver and the MCPM
>> driver code. The MCPM driver is only used on ARM(32) and contains
>> arm32 assembly and hence can't be built on ARM64. This patch splits
>> the code to
>>
>>    - ARM_CCI400_PORT_CTRL driver - depends on ARM && V7
>>    - ARM_CCI400_PMU driver
>>
>> Accessing the Peripheral ID2 register(PID2) on CCI-400, to detect
>> the revision of the chipset, is a secure operation. Hence, it prevents
>> us from running this on non-secure platforms. The issue is overcome by
>> explicitly mentioning the revision number of the CCI PMU in the device tree
>> binding. The device-tree binding has been updated with the new bindings.
>>
>> i.e,	arm-cci-400-pmu,r0 => revision 0
>> 	arm-cci-400-pmu,r1 => revision 1
>> 	arm-cci-400-pmu => (old) DEPRECATED
>>
>> The old binding has been DEPRECATED and must be used only on ARM32
>> system with secure access. We don't have a reliable dynamic way to detect
>> if the system is running secure. This series tries to use the best safe
>> method by relying on the availability of MCPM(as it was prior to the series).
>> It is upto the MCPM platform driver to decide, if the system is secure before
>> it goes ahead and registers its drivers and pokes the CCI. This series doesn't
>> address/solve the problem of MCPM. I will be happy to use a better approach,
>> if there is any.
>>
>> Tested on (non-secure)TC2 and Juno.
>>
>
> For the series:
> Tested-by: Sudeep Holla <sudeep.holla@....com> (on secure/MCPM TC2)
>

Thanks a lot for the testing

Suzuki

--
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/