On Wed, Mar 06, 2019 at 12:40:54PM +0000, Igor Druzhinin wrote: > This aperture doesn't exist in OVMF and trying to use it causes > failing assertions later in cases there are prefetchable and > non-prefetchable BARs following each other. This configuration is > quite likely with some PCI passthrough devices.
According to the PCIe spec, it's fine to place prefetchable BARs in non-prefetchable memory space. There's a note that says that most implementations will only have 1G of non-prefetchable memory, and that most scalable platforms will map 32bit BARs into non-prefetchable memory regardless of the prefetchable bit value. Shouldn't OVMF be fine with finding both prefetchable and non-prefetchable BARs, as long as the memory region is set to non-prefetchable? Does OVMF have the capability to position BARs by itself? If so we could skip of the placement done by hvmloader and just let OVMF position things where it see fit. Thanks, Roger. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
