Since v5.19, vfio-pci makes use of runtime power management on devices. This has the effect of potentially putting entire sub-hierarchies into lower power states, which has exposed some gaps in the PCI subsystem around power management support. The first issue is that lspci accesses the VPD sysfs interface, which does not provide the same power management wrappers as general config space. The next covers PME, where we attempt to skip devices based on their PCI power state, but don't protect changes to that state or look at the overall runtime power management state of the device. This latter patch addresses the issue noted by Eric in the follow-ups to v1 linked below. These patches are logically independent, but only together resolve an issue on Eric's system where a pair of endpoints bound to vfio-pci and unused by userspace drivers trigger faults through lspci and PME polling. Thanks, Alex v1: https://lore.kernel.org/all/20230707151044.1311544-1-alex.williamson@xxxxxxxxxx/ Alex Williamson (2): PCI/VPD: Add runtime power management to sysfs interface PCI: Fix runtime PM race with PME polling drivers/pci/pci.c | 23 ++++++++++++++++------- drivers/pci/vpd.c | 34 ++++++++++++++++++++++++++++++++-- 2 files changed, 48 insertions(+), 9 deletions(-) -- 2.40.1
