RE: [EXTERNAL] Re: [PATCH net-next] net: mana: Add handler for sriov configure

[Haiyang Zhang]

> -----Original Message-----
> From: Bjorn Helgaas <helgaas@xxxxxxxxxx>
> Sent: Friday, May 8, 2026 6:38 PM
> To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxxxxxxxx>
> Cc: linux-hyperv@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; KY Srinivasan
> <kys@xxxxxxxxxxxxx>; Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>; Wei Liu
> <wei.liu@xxxxxxxxxx>; Dexuan Cui <DECUI@xxxxxxxxxxxxx>; Long Li
> <longli@xxxxxxxxxxxxx>; Andrew Lunn <andrew+netdev@xxxxxxx>; David S.
> Miller <davem@xxxxxxxxxxxxx>; Eric Dumazet <edumazet@xxxxxxxxxx>; Jakub
> Kicinski <kuba@xxxxxxxxxx>; Paolo Abeni <pabeni@xxxxxxxxxx>; Bjorn Helgaas
> <bhelgaas@xxxxxxxxxx>; Simon Horman <horms@xxxxxxxxxx>; Shradha Gupta
> <shradhagupta@xxxxxxxxxxxxxxxxxxx>; Dipayaan Roy
> <dipayanroy@xxxxxxxxxxxxxxxxxxx>; Erni Sri Satya Vennela
> <ernis@xxxxxxxxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-
> pci@xxxxxxxxxxxxxxx; Paul Rosswurm <paulros@xxxxxxxxxxxxx>
> Subject: [EXTERNAL] Re: [PATCH net-next] net: mana: Add handler for sriov
> configure
> 
> On Fri, May 08, 2026 at 03:04:06PM -0700, Haiyang Zhang wrote:
> > From: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
> >
> > Add callback function for the pci_driver, sriov_configure.
> >
> > Also disable VF autoprobe when it runs as PF driver on bare metal,
> > since the hardware side may not have the VF ready immediately.
> >
> > Export pci_vf_drivers_autoprobe() so the driver can toggle the VF
> > autoprobe flag.
> 
> Technically pci_vf_drivers_autoprobe() doesn't *toggle* the autoprobe
> flag.  That would mean setting it to the opposite of its current
> value.
> 
> Here I would say "so the driver can prevent autoprobing of the VFs",
> which is the intent.
Thanks, I will change the wording.

> 
> Out of curiosity, how do the VFs eventually get probed?  I guess
> there's some other mechanism that tells you when they're ready, and
> you manually use sysfs 'sriov_drivers_autoprobe' to enable probing,
> then bind drivers to them via sysfs?
We have a user program talking to the Azure backplane to get that information.
@Paul Rosswurm, do you have more details?


> The prevention of autoprobing sounds like a critical part of this
> change; might be worth saying something in the subject, because "add
> sriov configure" doesn't include much information.
How about "Add handler for sriov configure with VF autoprobe off"?

Thanks,
- Haiyang