From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Xu <peterx@redhat.com>
Subject: Re: [PATCH kvm-unit-tests v5 13/14] pci: add msi support for
 32/64bit address
Date: Tue, 22 Nov 2016 12:59:20 +0800
Message-ID: <20161122045920.GA425@pxdev.xzpeter.org>
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To: Alexander Gordeev <agordeev@redhat.com>
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On Mon, Nov 21, 2016 at 08:27:52PM +0100, Alexander Gordeev wrote:

[...]

> > +void pci_cap_walk(struct pci_dev *dev)
> > +{
> > +	uint8_t cap_offset;
> > +	uint8_t cap_id;
> > +
> > +	cap_offset = pci_config_readb(dev->bdf, PCI_CAPABILITY_LIST);
> > +	while (cap_offset) {
> > +		cap_id = pci_config_readb(dev->bdf, cap_offset);
> > +		printf("PCI detected cap 0x%x\n", cap_id);
> > +		if (cap_handlers[cap_id])
> > +			cap_handlers[cap_id](dev, cap_offset);
> > +		cap_offset = pci_config_readb(dev->bdf, cap_offset + 1);
> > +	}
> > +}
> 
> Are you sure the function above is safe without range (sanity) checks?

No. :) But if something goes wrong, I guess that's possibly a QEMU PCI
bug. I can add some check if you think is necessary, like, make sure
the loop goes no more than a specific value?

Thanks,

-- peterx