On Thu, Feb 04, 2021 at 10:43:53AM +0100, Niklas Schnelle wrote: > The global UID uniqueness attribute exposes whether the platform > guarantees that the user-defined per-device UID attribute values > (/sys/bus/pci/device/<dev>/uid) are unique and can thus be used as > a global identifier for the associated PCI device. With this commit > it is exposed at /sys/bus/pci/zpci/unique_uids > > Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx> > --- > Documentation/ABI/testing/sysfs-bus-pci | 9 +++++++++ > drivers/pci/pci-sysfs.c | 21 +++++++++++++++++++++ > 2 files changed, 30 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci > index 25c9c39770c6..812dd9d3f80d 100644 > --- a/Documentation/ABI/testing/sysfs-bus-pci > +++ b/Documentation/ABI/testing/sysfs-bus-pci > @@ -375,3 +375,12 @@ Description: > The value comes from the PCI kernel device state and can be one > of: "unknown", "error", "D0", D1", "D2", "D3hot", "D3cold". > The file is read only. > +What: /sys/bus/pci/zpci/unique_uids No blank line before this new line? And why "zpci"? > +Date: February 2021 > +Contact: Niklas Schnelle <schnelle@xxxxxxxxxxxxx> > +Description: > + This attribute exposes the global state of UID Uniqueness on an > + s390 Linux system. If this file contains '1' the per-device UID > + attribute is guaranteed to provide a unique user defined > + identifier for that PCI device. If this file contains '0' UIDs > + may collide and do not provide a unique identifier. What are they "colliding" with? And where does the UID come from, the device itself or somewhere else? thanks, greg k-h
