forked from Minki/linux
51ef3a004b
PCI core handles save and restore of device state around reset, but when using pci_set_power_state() we can unintentionally trigger a soft reset of the device, where PCI core only restores the BAR state. If we're using vfio-pci's idle D3 support to try to put devices into low power when unused, this might trigger a reset when the device is woken for use. Also power state management by the user, or within a guest, can put the device into D3 power state with potentially limited ability to restore the device if it should undergo a reset. The PCI spec does not define the extent of a soft reset and many devices reporting soft reset on D3->D0 transition do not undergo a PCI config space reset. It's therefore assumed safe to unconditionally restore the remainder of the state if the device indicates soft reset support, even on a user initiated wakeup. Implement a wrapper in vfio-pci to tag devices reporting PM reset support, save their state on transitions into D3 and restore on transitions back to D0. Reported-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| trace.h | ||
| vfio_pci_config.c | ||
| vfio_pci_igd.c | ||
| vfio_pci_intrs.c | ||
| vfio_pci_nvlink2.c | ||
| vfio_pci_private.h | ||
| vfio_pci_rdwr.c | ||
| vfio_pci.c | ||