Re: [PATCH v2] driver core: Check drivers_autoprobe for all added devices

[Vincent Liu]

On 14 Oct 2025, at 21:07, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> 
>> In particular for the PCI devices, only
>> hot-plugged PCIe devices/VFs should be affected as the default value of
>> pci/drivers_autoprobe remains 1 and can only be cleared from userland.
> 
> I'm not sure what this last sentence is telling us.  Does
> "pci/drivers_autoprobe" refer to struct pci_sriov.drivers_autoprobe?
> If so, can you elaborate on the connection with struct
> subsys_private.drivers_autoprobe, which this patch tests?  I don't see
> anything in this patch related to pci_sriov.

No this patch has nothing to do with pci_sriov.drivers_autoprobe, this is
generic for all (pci) devices. pci/drivers_autoprobe refers to the
drivers_autoprobe sysfs attribute on the pci bus.

The last sentence is saying that this setting should only affect hot-plugged
devices because I think there is no way for pci/drivers_autoprobe to be 0 
for cold plugged devices? But thinking more about this, I don’t think this
adds much value to the commit message because the drivers_autoprobe
is not intended for cold-plugged devices anyway. I’ll remove it.

> As far as I can tell, this patch is generic with respect to
> conventional PCI vs PCIe.  If so, I'd use "PCI" everywhere instead of
> a mix of PCI and PCIe.

Yes you are right, this is generic. I used PCIe purely because of the
“hot-plugging”, but happy to use PCI everywhere.

> Add "()" after function names to make them easily recognizable as
> functions.
> 
> s/respsect/respect/
> s/but this should be the/which is the/  # maybe? not sure what you intend

Ok.

Below is a rephrased commit message to incorporate the feedback.

Thanks,
Vincent

-- >8 --

Subject: [PATCH v2] driver core: Check drivers_autoprobe for all added devices

When a device is hot-plugged, the drivers_autoprobe sysfs attribute is
not checked (at least for PCI devices). This means that
drivers_autoprobe is not working as intended, e.g. hot-plugged PCI
devices will still be autoprobed and bound to drivers even with
drivers_autoprobe disabled.

Make sure all devices check drivers_autoprobe by pushing the
drivers_autoprobe check into device_initial_probe(). This will only
affect devices on the PCI bus for now as device_initial_probe() is only
called by pci_bus_add_device() and bus_probe_device(), but
bus_probe_device() already checks for autoprobe, so callers of
bus_probe_device() should not observe changes on autoprobing.

Any future callers of device_initial_probe() will respect the
drivers_autoprobe sysfs attribute, which is the intended purpose of
drivers_autoprobe.

Signed-off-by: Vincent Liu <vincent.liu@xxxxxxxxxxx>

Link: https://lore.kernel.org/20251001151508.1684592-1-vincent.liu@xxxxxxxxxxx