#define PCIM_BAR_MEM_BASE 0xfffffffffffffff0ULL
#define PCIM_BAR_MEM_BASE 0xfffffffffffff000ULL
sys/dev/PCI/pcireg.h makes the min size of a memory BAR equal to 0x1000 or 4096
bytes and it lets me passthrough the device. Any objections to this strategy?
On December 2, 2015 11:54:03 PM GMT+01:00, Neel Natu <neeln...@gmail.com> wrote:
>On Wed, Dec 2, 2015 at 3:13 AM, G. Amanakis via freebsd-virtualization
>> I am facing the following problem:
>> on a X9SCM with an E3-1220Lv2 I am trying to passthrough the
>onboard usb controllers. I disable the usb module from the kernel
>config and using pptdev the controllers are assigned to ppt devices.
>However running bhyve on FreeBSD 10.2 with:
>> sudo bhyve -AI -H -P -s 0:0,hostbridge -s 1:0,lpc -s
>2:0,virtio-net,tap0 -s 3:0,virtio-blk,./linux.img -s
>4:0,passthru,0/29/0 -l com1,stdio -c 2 -m 2048M linuxguest
>> returns :
>> passthru device 0/29/0 BAR 0: base 0xdf823000 or size 0x400 not
>> The problem probably that the length of the bar is smaller and not
>aligned with the pagesize. Could the length of the BAR be modified in
>order to perform the pci passthrough?
>Yes, that's correct - the size of the BAR is not a multiple of the
>page size which leads to the error. If this BAR is mapped into the
>guest's address space then it will "leak" an additional 3K into the
>guest (since the minimum nested mapping is 4KB in size).
>It is hard to fix this in the general case if you want to truly
>passthrough the BAR to the guest.
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