Re: [PATCH v2 1/1] PCI/hotplug: Add 'uevent' sysfs attribute to trigger slot events

[Ramesh Errabolu <ramesh@linux.ibm.com>]

Thanks for testing and also giving me the review-by

Regards,
Ramesh


On 4/17/2026 4:53 AM, Niklas Schnelle wrote:
> On Thu, 2026-04-16 at 16:39 -0500, Ramesh Errabolu wrote:
>> Add a write-only 'uevent' sysfs attribute for synthesizing
>> uevents for a PCI slot. This extends the existing uevent
>> support which emits a KOBJ_ADD uevent in pci_hp_add() with
>> the ability to replay such uevents for cold plugged devices.
>> As such events are only emitted by hotplug capable PCI slots
>> so is the support for synthesizing them.
>>
>> The change was validated by manually triggering 'add' uevent
>> for a specific hotplug PCI slot:
>>
>>      $ echo "add $(uuidgen)" | sudo tee   \
>>                  /sys/bus/pci/slots/<slot-id>/uevent
>>
>> Signed-off-by: Ramesh Errabolu <ramesh@linux.ibm.com>
>> ---
>>   drivers/pci/hotplug/pci_hotplug_core.c | 25 +++++++++++++++++++++++++
>>   1 file changed, 25 insertions(+)
>>
> Sorry for the review delay. This looks good to me and will really help
> with udev rule execution for devices which are discovered in standby
> state during boot and thus currently don't create any uevents. Of
> course to work by default this still requires a systemd/udev addition
> that I know you're also working on.
>
> Consequently, I tested the uevent synthesization with both slots with a
> configured (slot powered on) and standby (slot powered off) PCI
> function.
>
> Feel free to add:
>
> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
> Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
>
> Thanks,
> Niklas