linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Borislav Petkov <bp@amd64.org>
To: Robert Whitton <rwhitton@iee.org>
Cc: Clemens Ladisch <clemens@ladisch.de>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: Background memory scrubbing
Date: Wed, 20 Apr 2011 18:01:26 +0200	[thread overview]
Message-ID: <20110420160125.GC2312@gere.osrc.amd.com> (raw)
In-Reply-To: <18563.1303314382@jupiter.eclipse.co.uk>

On Wed, Apr 20, 2011 at 04:46:22PM +0100, Robert Whitton wrote:
> 
> > On Wed, Apr 20, 2011 at 05:19:41PM +0200, Clemens Ladisch wrote:
> > > > Unfortunately in common with a large number of hardware platforms
> > > > background scrubbing isn't supported in the hardware (even though ECC
> > > > error correction is supported) and thus there is no BIOS option to
> > > > enable it.
> > > 
> > > Which hardware platform is this? AFAICT all architectures with ECC
> > > (old AMD64, Family 0Fh, Family 10h) also have scrubbing support.
> > > If your BIOS is too dumb, just try enabling it directly (bits 0-4 of
> > > PCI configuration register 0x58 in function 3 of the CPU's northbridge
> > > device, see the BIOS and Kernel's Developer's Guide for details).
> > 
> > Or even better, if on AMD, you can build the amd64_edac module
> > (CONFIG_EDAC_AMD64) and do
> > 
> > echo  > /sys/devices/system/edac/mc/mc/sdram_scrub_rate
> > 
> > where x is the scrubbing bandwidth in bytes/sec and y is the memory
> > controller on the machine, i.e. node.
>
> Unfortunately that also isn't an option on my platform(s). There surely must be a way for a module to be able to get a mapping for each physical page of memory in the system and to be able to use that mapping to do atomic read/writes to scrub the memory.

For such questions I've added just the right ML to Cc :).

-- 
Regards/Gruss,
Boris.

Advanced Micro Devices GmbH
Einsteinring 24, 85609 Dornach
General Managers: Alberto Bozzo, Andrew Bowd
Registration: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

       reply	other threads:[~2011-04-20 16:01 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <18563.1303314382@jupiter.eclipse.co.uk>
2011-04-20 16:01 ` Borislav Petkov [this message]
2011-04-25 16:53   ` Chris Friesen

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=20110420160125.GC2312@gere.osrc.amd.com \
    --to=bp@amd64.org \
    --cc=clemens@ladisch.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=rwhitton@iee.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