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

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, May 08, 2026 at 10:47:14PM +0000, Haiyang Zhang wrote:
> > -----Original Message-----
> > From: Bjorn Helgaas <helgaas@kernel.org>
> > Sent: Friday, May 8, 2026 6:38 PM
> > To: Haiyang Zhang <haiyangz@linux.microsoft.com>
> > Cc: linux-hyperv@vger.kernel.org; netdev@vger.kernel.org; KY Srinivasan
> > <kys@microsoft.com>; Haiyang Zhang <haiyangz@microsoft.com>; Wei Liu
> > <wei.liu@kernel.org>; Dexuan Cui <DECUI@microsoft.com>; Long Li
> > <longli@microsoft.com>; Andrew Lunn <andrew+netdev@lunn.ch>; David S.
> > Miller <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>; Jakub
> > Kicinski <kuba@kernel.org>; Paolo Abeni <pabeni@redhat.com>; Bjorn Helgaas
> > <bhelgaas@google.com>; Simon Horman <horms@kernel.org>; Shradha Gupta
> > <shradhagupta@linux.microsoft.com>; Dipayaan Roy
> > <dipayanroy@linux.microsoft.com>; Erni Sri Satya Vennela
> > <ernis@linux.microsoft.com>; linux-kernel@vger.kernel.org; linux-
> > pci@vger.kernel.org; Paul Rosswurm <paulros@microsoft.com>
> > 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@microsoft.com>
> > >
> > > 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"?

OK by me :)