Re: [PATCH 0/3] add dynamic PCI device of_node creation for overlay

[Christoph Hellwig]

On Mon, May 09, 2022 at 10:40:12PM +0200, Andy Shevchenko wrote:
> > hotpluggable card?  Do the systems that you anticipate plugging the
> > card into support hotplug?
> 
> Any PCIe card is potentially hotpluggable (seems nobody actually cares
> in 90%+ drivers in the Linux kernel). But what I have heard in a
> thread (not this one IIRC) is that the card may have pluggable modules
> and it would be nice to change configuration and notify OS somehow. I
> might be mistaken if it's the case here or not.

Well.  M.2 for example is not hotpluggable, as are soldered on BGA
devices or a lot of not quite PCIe devices that actually sit on CPUs
or shipset components.  But for all but the last category an upstream
bridge could still be hot plugged, so not supporting it in drivers is
indeed generally speaking a bad idea.