linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: catalin.marinas@arm.com (Catalin Marinas)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] clocksource: arch_timer: Only use the virtual counter (CNTVCT) on arm64
Date: Wed, 10 Dec 2014 11:23:17 +0000	[thread overview]
Message-ID: <20141210112317.GA13994@e104818-lin.cambridge.arm.com> (raw)
In-Reply-To: <548828C6.6030500@linaro.org>

On Wed, Dec 10, 2014 at 11:04:38AM +0000, Daniel Lezcano wrote:
> On 12/10/2014 12:02 PM, Catalin Marinas wrote:
> > Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical
> > timers when requested) introduces the use of physical counters in the
> > ARM architected timer driver. However, he arm64 kernel uses CNTVCT in
> > VDSO. When booting in EL2, the kernel switches to the physical timers to
> > make things easier for KVM but it continues to use the virtual counter
> > both in user and kernel. While in such scenario CNTVCT == CNTPCT (since
> > CNTVOFF is initialised by the kernel to 0), we want to spot firmware
> > bugs corrupting CNTVOFF early (which would affect CNTVCT).
> >
> > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
> > Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
> > Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> > ---
> >
> > Daniel,
> >
> > Do you plan to take this patch and push into mainline (ideally before -rc1)?
> > Otherwise we can push it via the arm64 tree.
> 
> I will take care of it.

Thanks.

-- 
Catalin

  reply	other threads:[~2014-12-10 11:23 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-10 11:02 [PATCH] clocksource: arch_timer: Only use the virtual counter (CNTVCT) on arm64 Catalin Marinas
2014-12-10 11:04 ` Daniel Lezcano
2014-12-10 11:23   ` Catalin Marinas [this message]
2014-12-15 10:58   ` Mark Rutland
2014-12-15 13:27     ` Daniel Lezcano

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20141210112317.GA13994@e104818-lin.cambridge.arm.com \
    --to=catalin.marinas@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).