linux-kernel - Re: [PATCH] irqchip/gic-v3: do not access GICR

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:   Wed, 13 Jun 2018 09:45:53 +0100
From:   Sudeep Holla <sudeep.holla@....com>
To:     Srinivas Kandagatla <srinivas.kandagatla@...aro.org>
Cc:     Marc Zyngier <marc.zyngier@....com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Jason Cooper <jason@...edaemon.net>,
        open list <linux-kernel@...r.kernel.org>,
        linux-arm-msm@...r.kernel.org,
        "Nayak, Rajendra" <rnayak@...eaurora.org>,
        bjorn.andersson@...aro.org, sboyd@...nel.org,
        Sudeep Holla <sudeep.holla@....com>
Subject: Re: [PATCH] irqchip/gic-v3: do not access GICR_WAKER if its secured register.

On Wed, Jun 13, 2018 at 9:21 AM, Srinivas Kandagatla
<srinivas.kandagatla@...aro.org> wrote:
>
>
> On 12/06/18 17:34, Marc Zyngier wrote:
>>
>> I suggest you find out how the GIC has been integrated on this
>> platform. If you take a fault on accessing this register, this very
>> much looks like an integration bug, and it should be quirked as such.
>
> Thanks for the suggestion, This is a bug in the firmware which is
> restricting access to this register. We have been working around this bug
> for more than 2 years due to this. Now this platform support is in mainline
> and We/I have no hope that this will be fixed in near future atleast for
> this platform.
>

>From what you are saying, you were aware of the firmware bug for 2 years as
you had work-around from then. I wish the firmware had come up with the fix
in those lost 2 years. I understand if it was discovered now, but that doesn't
seem to be the case here.

Firmware fixes are now becoming inevitable, so the attitude that firmware can't
be fixed has to slowing change. I am not saying I am against the quirk, but in
general I have seen the firmware support of QCOM parts are really bad. I waited
for almost 2 years for PSCI firmware on previous dragonboard where developer
are trying to upstream some feature.

--
Regards,
Sudeep