Subject: Re: [PATCH 1/1] pci: Block config access during BIST (resend)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Matthew Wilcox <matthew@wil.cx>
Cc: Brian King <brking@us.ibm.com>, Greg KH <greg@kroah.com>,
       Andi Kleen <ak@muc.de>, Paul Mackerras <paulus@samba.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>, linux-pci@atrey.karlin.mff.cuni.cz
In-Reply-To: <20050201154400.GC10088@parcelfarce.linux.theplanet.co.uk>
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Date: Wed, 02 Feb 2005 09:58:40 +1100
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On Tue, 2005-02-01 at 15:44 +0000, Matthew Wilcox wrote:

> 
> > +void pci_unblock_user_cfg_access(struct pci_dev *dev)
> > +{
> > +	unsigned long flags;
> > +
> > +	spin_lock_irqsave(&pci_lock, flags);
> > +	dev->block_ucfg_access = 0;
> > +	spin_unlock_irqrestore(&pci_lock, flags);
> > +}
> 
> If we've done a write to config space while the adapter was blocked,
> shouldn't we replay those accesses at this point?

I think no. In fact, I would be ok returning errors on writes from
userland. Need to do config space writes from userland is rare, must
more than reads, and if whatever does it can't properly arbitrate with
what's going on in the kernel, then it's broken.

Ben.


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