Re: [PATCH v1] PCI: Add write-only 'uevent' sysfs attribute for PCI slots

[Leon Romanovsky <leon@kernel.org>]

On Thu, Feb 26, 2026 at 11:53:32AM -0600, Ramesh Errabolu wrote:
> 
> On 2/26/2026 2:34 AM, Leon Romanovsky wrote:
> > On Wed, Feb 25, 2026 at 09:08:15AM -0600, Ramesh Errabolu wrote:
> > > Add a new write-only 'uevent' attribute to PCI slot sysfs
> > > entries. This provides a mechanism for userspace to explicitly
> > > synthesize PCI slot uevents when needed.
> > > 
> > > For cold-plugged PCI devices, slots may be created before
> > > udev is ready to receive events, causing the initial 'add'
> > > uevents to be missed. As a result, slot specific udev
> > > rules that define naming, permissions, and related policies,
> > > are not applied at boot. Allowing userspace to resynthesize
> > > the 'add' uevent ensures these rules are processed correctly.
> > This patch sounds like a hack to me. AFAIK, "udevadm trigger"
> > performs exactly that.
> > 
> > Thanks
> 
> AFAIK, PCI slots do not yet raise a uevent. 

Right

> Secondly there is no uevent attribute in slot-id directory to submit requests to raise a uevent. This 
> patch fills that gap

Please start from the beginning and explain what you mean by 'the gap'.
Which scenario failed before and began working after this patch? From your
description, it sounds like the behavior should already be covered by the
'udevadm trigger' command.

I want to note that drivers/pci/slot.c has remained largely unchanged since 2008.

Thanks