1What:           /sys/bus/pci/drivers/pciback/quirks
2Date:           Oct 2011
3KernelVersion:  3.1
4Contact:        xen-devel@lists.xenproject.org
5Description:
6                If the permissive attribute is set, then writing a string in
7                the format of DDDD:BB:DD.F-REG:SIZE:MASK will allow the guest
8                to write and read from the PCI device. That is Domain:Bus:
9                Device.Function-Register:Size:Mask (Domain is optional).
10                For example:
11                #echo 00:19.0-E0:2:FF > /sys/bus/pci/drivers/pciback/quirks
12                will allow the guest to read and write to the configuration
13                register 0x0E.
14
15What:           /sys/bus/pci/drivers/pciback/allow_interrupt_control
16Date:           Jan 2020
17KernelVersion:  5.6
18Contact:        xen-devel@lists.xenproject.org
19Description:
20                List of devices which can have interrupt control flag (INTx,
21                MSI, MSI-X) set by a connected guest. It is meant to be set
22                only when the guest is a stubdomain hosting device model (qemu)
23                and the actual device is assigned to a HVM. It is not safe
24                (similar to permissive attribute) to set for a devices assigned
25                to a PV guest. The device is automatically removed from this
26                list when the connected pcifront terminates.
27