qemu/hw/vfio
Alex Williamson d0d1cd70d1 vfio/pci: Improve extended capability comments, skip masked caps
Since commit 4bb571d857 ("pci/pcie: don't assume cap id 0 is
reserved") removes the internal use of extended capability ID 0, the
comment here becomes invalid.  However, peeling back the onion, the
code is still correct and we still can't seed the capability chain
with ID 0, unless we want to muck with using the version number to
force the header to be non-zero, which is much uglier to deal with.
The comment also now covers some of the subtleties of using cap ID 0,
such as transparently indicating absence of capabilities if none are
added.  This doesn't detract from the correctness of the referenced
commit as vfio in the kernel also uses capability ID zero to mask
capabilties.  In fact, we should skip zero capabilities precisely
because the kernel might also expose such a capability at the head
position and re-introduce the problem.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Reported-by: Jintack Lim <jintack@cs.columbia.edu>
Tested-by: Jintack Lim <jintack@cs.columbia.edu>
2017-02-22 13:19:58 -07:00
..
amd-xgbe.c all: Clean up includes 2016-02-23 12:43:05 +00:00
calxeda-xgmac.c hw/vfio: Clean up includes 2016-01-29 15:07:24 +00:00
common.c vfio: allow to notify unmap for very large region 2017-02-17 21:52:31 +02:00
Makefile.objs hw/vfio: Add CONFIG switches for calxeda-xgmac and amd-xgbe 2017-02-10 13:12:03 -07:00
pci-quirks.c hw/vfio/pci-quirks: Set category of the "vfio-pci-igd-lpc-bridge" device 2017-02-10 13:12:03 -07:00
pci.c vfio/pci: Improve extended capability comments, skip masked caps 2017-02-22 13:19:58 -07:00
pci.h vfio/pci: Pass an error object to vfio_pci_igd_opregion_init 2016-10-17 10:57:59 -06:00
platform.c vfio/platform: Pass an error object to vfio_base_device_init 2016-10-17 10:58:01 -06:00
spapr.c memory: Replace skip_dump flag with "ram_device" 2016-10-31 09:53:03 -06:00
trace-events vfio: trace map/unmap for notify as well 2017-02-17 21:52:31 +02:00