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Message-ID: <1446661738.3692.129.camel@redhat.com>
Subject: Re: [patch] vfio: make an array larger
From: Alex Williamson <alex.williamson@redhat.com>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Frank Blaschka <frank.blaschka@de.ibm.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Date: Wed, 04 Nov 2015 11:28:58 -0700
In-Reply-To: <20151104182022.GJ7289@mwanda>
References: <20151104132624.GC20966@mwanda>
	 <1446656080.3692.112.camel@redhat.com> <20151104182022.GJ7289@mwanda>
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On Wed, 2015-11-04 at 21:20 +0300, Dan Carpenter wrote:
> Sorry, I should have said that I am on linux-next at the start.
> 
> > > -static u8 pci_cap_length[] = {
> > > +static u8 pci_cap_length[PCI_CAP_ID_MAX + 1] = {
> > >  	[PCI_CAP_ID_BASIC]	= PCI_STD_HEADER_SIZEOF, /* pci config header */
> > >  	[PCI_CAP_ID_PM]		= PCI_PM_SIZEOF,
> > >  	[PCI_CAP_ID_AGP]	= PCI_AGP_SIZEOF,
> > 
> > This doesn't make a whole lot of sense to me.  The last entry we define
> > is:
> > 
> >         [PCI_CAP_ID_AF]         = PCI_CAP_AF_SIZEOF,
> 
> Yes.
> 
> > };
> > 
> > and PCI_CAP_ID_MAX is defined as:
> > 
> > #define  PCI_CAP_ID_MAX         PCI_CAP_ID_AF
> 
> No.  I am on linux-next and we appear to have added a new element
> beyond PCI_CAP_ID_AF.
> 
> #define  PCI_CAP_ID_AF          0x13    /* PCI Advanced Features */
> #define  PCI_CAP_ID_EA          0x14    /* PCI Enhanced Allocation */
> #define  PCI_CAP_ID_MAX         PCI_CAP_ID_EA
> 
> > 
> > So the array is implicitly sized to PCI_CAP_ID_MAX + 1 already, this
> > doesn't make it any larger.
> 
> In linux-next it makes it larger.  But also explicitly using
> PCI_CAP_ID_MAX + 1 is cleaner as well as fixing the bug in case we add
> more elements later again.

Ok, all the pieces line up now.  Please add mention of that to the
commit log and I'll look for the respin including the same for
pci_ext_cap_length.  Thanks for spotting this!

Alex