On Thu, Feb 16, 2017 at 11:04:46AM +0800, Peter Xu wrote: > On Wed, Feb 15, 2017 at 07:52:35PM -0700, Alex Williamson wrote: > > On Thu, 16 Feb 2017 10:35:28 +0800 > > Peter Xu <pet...@redhat.com> wrote: > > > > > On Wed, Feb 15, 2017 at 10:49:47PM +0200, Michael S. Tsirkin wrote: > > > > VFIO actually wants to create a capability with ID == 0. > > > > This is done to make guest drivers skip the given capability. > > > > pcie_add_capability then trips up on this capability > > > > when looking for end of capability list. > > > > > > > > To support this use-case, it's easy enough to switch to > > > > e.g. 0xffffffff for these comparisons - we can be sure > > > > it will never match a 16-bit capability ID. > > > > > > > > Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > > > > > > Reviewed-by: Peter Xu <pet...@redhat.com> > > > > > > Two nits: > > > > > > (1) maybe we can s/0xffffffff/0xffff/ in the whole patch since ecap_id > > > is 16 bits > > > > The former is used because it's beyond the address space of a valid > > capability. Using 0xffff just makes the situation different, not > > better. > > But isn't pcie_find_capability_list() defining cap_id parameter as > uint16_t? In that case, 0xffffffff will be the same as 0xffff since > we'll just take the lower 16 bits?
Alex helpped pointing out that this patch has touched the parameter while I didn't notice that. Sorry. :( Please take my r-b and ignore the two nits. Thanks, -- peterx
