linux-kernel - Re: [PATCH v6 2/3] DT/arm,gic-v3-its: add reset-on-suspend property

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, 8 Feb 2018 13:46:50 +0000
From:   Mark Rutland <mark.rutland@....com>
To:     Derek Basehore <dbasehore@...omium.org>
Cc:     linux-kernel@...r.kernel.org, Soby.Mathew@....com,
        sudeep.holla@....com, devicetree@...r.kernel.org,
        robh+dt@...nel.org, linux-pm@...r.kernel.org,
        rafael.j.wysocki@...el.com, tglx@...utronix.de,
        briannorris@...omium.org, marc.zyngier@....com
Subject: Re: [PATCH v6 2/3] DT/arm,gic-v3-its: add reset-on-suspend property

On Wed, Feb 07, 2018 at 06:36:47PM -0800, Derek Basehore wrote:
> This adds documentation for the new reset-on-suspend property. This
> property enables saving and restoring the ITS for when it loses state
> in system suspend.
> 
> Signed-off-by: Derek Basehore <dbasehore@...omium.org>
> ---
>  Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt
> index 0a57f2f4167d..a470147d4f14 100644
> --- a/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt
> +++ b/Documentation/devicetree/bindings/interrupt-controller/arm,gic-v3.txt
> @@ -78,6 +78,9 @@ These nodes must have the following properties:
>  Optional:
>  - socionext,synquacer-pre-its: (u32, u32) tuple describing the untranslated
>    address and size of the pre-ITS window.
> +- reset-on-suspend: Boolean property. Indicates that the ITS state is
> +  reset on suspend. The state is then saved on suspend and restored on
> +  resume.

The latter sentence reads like a description of SW policy, rather than a
description of what the HW does. I don't think that should be here
(though it might be worth noting the FW will not restore state).

Which state is lost? Is "ITS state" a well-defined term?

By suspend do you mean a PSCI_SYSTEM_SUSPEND, or potentially other
cases?

Thanks,
Mark.