linux-kernel - Re: [PATCH 01/01][retry 3] x86: L3 cache index disable for 2.6.26

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Message-ID: <20080814154605.GB27141@elf.ucw.cz>
Date:	Thu, 14 Aug 2008 17:46:05 +0200
From:	Pavel Machek <pavel@...e.cz>
To:	"Langsdorf, Mark" <mark.langsdorf@....com>
Cc:	Greg KH <greg@...ah.com>,
	"Deguara, Joachim" <joachim.deguara@....com>, gregkh@....cz,
	tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 01/01][retry 3] x86: L3 cache index disable for 2.6.26

Hi!

> > > +        val |= 0xc0000000;
> > > +        pci_write_config_dword(dev, 0x1BC + index * 4, val 
> > & ~0x40000000);
> > > +        wbinvd();
> > > +        pci_write_config_dword(dev, 0x1BC + index * 4, val);
> > 
> > Should it do if capable() test before doing such stuff?
> 
> I don't think so.  If it got this far, it is an AMD processor
> from family 0x10 or later, so it has wbinvd().

No, I meant we should check for permissions. Filesystem permissions
are traditionaly not enough for stuff like this. if
(capable(CAP_ADMIN)) or something?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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