qemu/hw/vfio
Alex Williamson 24acf72b9a vfio: Handle zero-length sparse mmap ranges
As reported in the link below, user has a PCI device with a 4KB BAR
which contains the MSI-X table.  This seems to hit a corner case in
the kernel where the region reports being mmap capable, but the sparse
mmap information reports a zero sized range.  It's not entirely clear
that the kernel is incorrect in doing this, but regardless, we need
to handle it.  To do this, fill our mmap array only with non-zero
sized sparse mmap entries and add an error return from the function
so we can tell the difference between nr_mmaps being zero based on
sparse mmap info vs lack of sparse mmap info.

NB, this doesn't actually change the behavior of the device, it only
removes the scary "Failed to mmap ... Performance may be slow" error
message.  We cannot currently create an mmap over the MSI-X table.

Link: http://lists.nongnu.org/archive/html/qemu-discuss/2016-10/msg00009.html
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-31 09:53:03 -06:00
..
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: Handle zero-length sparse mmap ranges 2016-10-31 09:53:03 -06:00
Makefile.objs vfio: spapr: Add DMA memory preregistering (SPAPR IOMMU v2) 2016-07-05 14:30:54 +10:00
pci-quirks.c vfio/pci: Fix vfio_rtl8168_quirk_data_read address offset 2016-10-17 10:58:02 -06:00
pci.c vfio: fix duplicate function call 2016-10-17 10:58:03 -06:00
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/pci: Conversion to realize 2016-10-17 10:58:01 -06:00