On 03/15/2016 09:40 PM, Or Gerlitz wrote:
On Tue, Mar 15, 2016 at 12:19 PM, Alexey Kardashevskiy <a...@ozlabs.ru> wrote:
This reverts commit 85743f1eb34548ba4b056d2f184a3d107a3b8917.
Without this revert, POWER "pseries" KVM guests with a VF passed to a guest
using VFIO fail to bring the driver up:
mlx4_core: Mellanox ConnectX core driver v2.2-1 (Feb, 2014)
mlx4_core: Initializing 0000:00:00.0
mlx4_core 0000:00:00.0: enabling device (0000 -> 0002)
mlx4_core 0000:00:00.0: Detected virtual function - running in slave mode
mlx4_core 0000:00:00.0: Sending reset
mlx4_core 0000:00:00.0: Sending vhcr0
mlx4_core 0000:00:00.0: HCA minimum page size:512
mlx4_core 0000:00:00.0: UAR size:4096 != kernel PAGE_SIZE of 65536
mlx4_core 0000:00:00.0: Failed to obtain slave caps
Both host and guest use 64K system pages.
How to fix this properly? Thanks.
The commit message says:
"[..] Regarding backward compatibility in SR-IOV, if hypervisor has
this new code, the virtual OS must be updated. [...]"
So with v4.5 as a host, there is no actual distro available today to use as
a guest in the next 6 months (or whatever it takes to backport this
partucular patch back there).
You could have added a module parameter to enforce the old behavoir, at
least...
And sorry but from the original commit log I could not understand why
exactly all existing guests need to be broken. Could you please point me to
a piece of documentation describing all this UAR bisuness (what is UAR, why
128 UARs are required and for what, etc). Thanks.
--
Alexey
