[F/H/I/J/Unstable][SRU][PATCH 0/1] Unblock setting vid 0 for VF in case PF isn't eswitch manager

[Po-Hsu Lin]

[Impact]
There is an issue with hypervisor host side mlx5 driver operation on
Bluefield devices in kernels <=5.16

>From patch description:
When using libvirt to passthrough VF to VM it will always set the VF vlan
to 0 even if user didn’t request it, this will cause libvirt to fail to
boot in case the PF isn't eswitch owner.

Example of such case is the DPU host PF which isn't eswitch manager, so
any attempt to passthrough VF of it using libvirt will fail.

[Fix]
* 7846665d net/mlx5e: Unblock setting vid 0 for VF in case PF isn't
 eswitch manager

This patch can be cherry-picked into Impish and newer kernels, but it
requires some backport work on F/H due to they're missing commit
b55b3538 that split the legacy code out.

The ESW_ALLOWED marco was later converted into a helper routine in
commit b16f2bb6.

[Test]
Test kernels can be found here:
F: https://people.canonical.com/~phlin/kernel/lp-1957753-mlx5e/F/
H: https://people.canonical.com/~phlin/kernel/lp-1957753-mlx5e/H/
I: https://people.canonical.com/~phlin/kernel/lp-1957753-mlx5e/I/
J: https://people.canonical.com/~phlin/kernel/lp-1957753-mlx5e/J/

Kernels tested on a SUT with this device by Dmitrii Shcherbakov, test
passed with positive feedback.

[Where problems could occur]
If this patch is erroneous, it might cause issue to this mlx5 driver
with certain operations (setting vid 0). And other programs such as
libvirt that depends on this return value might be affected as well.

Maor Dickman (1):
  net/mlx5e: Unblock setting vid 0 for VF in case PF isn't eswitch
    manager

 drivers/net/ethernet/mellanox/mlx5/core/esw/legacy.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

-- 
2.7.4