Re: [PATCH net-next v7 5/6] net: ngbe: add sriov function support

[Jakub Kicinski <kuba@kernel.org>]

On Tue, 11 Feb 2025 19:14:54 +0800 mengyuanlou@net-swift.com wrote:
> Due to hardware design, when 6 vfs are assigned. 
> +------------------------------------------------------------+
> |        | pf | pf  | vf5 | vf4 | vf3 | vf2 | vf1 | vf0 | pf |
> |--------|----|-----|-----|-----|-----|-----|-----|-----|----|
> | vector | 0  | 1   | 2   | 3   | 4   | 5   | 6   | 7   | 8  |
> +------------------------------------------------------------+
> 
> When 7 vfs are assigned. 
> +------------------------------------------------------------+
> |        | pf | vf6 | vf5 | vf4 | vf3 | vf2 | vf1 | vf0 | pf |
> |--------|----|-----|-----|-----|-----|-----|-----|-----|----|
> | vector | 0  | 1   | 2   | 3   | 4   | 5   | 6   | 7   | 8  |
> +------------------------------------------------------------+
> 
> When num_vfs < 7, pf can use 0 for misc and 1 for queue.
> But when num_vfs == 7, vector 1 is assigned to vf6.
> 1. Alloc 9 irq vectors, but only request_irq for 0 and 8. 
> 2. Reuse interrupt vector 0.

Do you have proper synchronization in place to make sure IRQs
don't get mis-routed when SR-IOV is enabled?
The goal should be to make sure the right handler is register
for the IRQ, or at least do the muxing earlier in a safe fashion.
Not decide that it was a packet IRQ half way thru a function called
ngbe_msix_other