linux-kernel - Re: [PATCH v4] ARM: perf: save/restore pmu registers in pm notifier

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: <20140703175706.GI17372@arm.com>
Date:	Thu, 3 Jul 2014 18:57:06 +0100
From:	Will Deacon <will.deacon@....com>
To:	Neil Zhang <zhangwm@...vell.com>
Cc:	Sudeep Holla <Sudeep.Holla@....com>,
	"'linux@....linux.org.uk'" <linux@....linux.org.uk>,
	"'linux-arm-kernel@...ts.infradead.org'" 
	<linux-arm-kernel@...ts.infradead.org>,
	"'linux-kernel@...r.kernel.org'" <linux-kernel@...r.kernel.org>,
	"'devicetree@...r.kernel.org'" <devicetree@...r.kernel.org>
Subject: Re: [PATCH v4] ARM: perf: save/restore pmu registers in pm notifier

On Mon, Jun 30, 2014 at 11:39:15AM +0100, Neil Zhang wrote:
> > > > I will prepare another patch to add DT description under PMU since
> > > > there is no generic power domain support for pm notifier if no other
> > > concerns.
> > > > We can change the manner if there is generic power domain support
> > > > for
> > > pm notifier later.
> > > > Thanks.
> > >
> > > No, please don't add any DT bindings for power domains specific to PMU
> > > node.
> > > We can't change the DT bindings once added.
> > >
> > > As I pointed out the DT bindings for generic power domains are under
> > > discussion.
> > > See if you can reuse it, if not help in extending it so that it can be used.
> > >
> > 
> > Sorry for reply later.
> > As I said before the under discussed generic power domain is not suitable for
> > CPU peripherals since they are all known belong to CPU or cluster power
> > domain.
> > If we want to follow the way they are discussion, we need to register core
> > and cluster power provider, and need vfp/gic/pmu etc to require them.
> > Is it really suitable?
> > 
> Do you have any comments?
> If no, I would like to put it under PMU node.

Sudeep is a better person to comment than me, but I'd still rather this was
handled more generically as opposed to a PMU-specific hack. I don't see a
problem including GIC and VFP here, but only when we actually need to
save/restore them (i.e. what the hardware guys went crazy with the power
domains).

Will
--
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/