Document how driver binding works during a Live Update and what the PCI core expects of drivers and users. Note that this is only a description of the current division of responsibilities. These can change in the future if we decide.
Reviewed-by: Pasha Tatashin <[email protected]> Reviewed-by: Pranjal Shrivastava <[email protected]> Reviewed-by: Samiullah Khawaja <[email protected]> Signed-off-by: David Matlack <[email protected]> --- drivers/pci/liveupdate.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/pci/liveupdate.c b/drivers/pci/liveupdate.c index 00776260ad6f..ec8db86ed66d 100644 --- a/drivers/pci/liveupdate.c +++ b/drivers/pci/liveupdate.c @@ -123,6 +123,20 @@ * * * The device cannot be a Virtual Function (VF). * * The device cannot be behind a PCI-to-PCI bridge. + * + * Driver Binding + * ============== + * + * In the outgoing kernel, the driver must ensure that it does not release a + * device between pci_liveupdate_preserve() and pci_liveupdate_unpreserve(). + * + * In the incoming kernel, the driver must ensure that it does not release a + * preserved device between probe() and pci_liveupdate_finish(). + * + * It is the user's responsibility to ensure that incoming preserved devices are + * bound to the correct driver. The PCI core does not protect against a device + * getting preserved by driver A in the outgoing kernel and then getting bound + * to driver B in the incoming kernel. */ #define pr_fmt(fmt) "PCI: liveupdate: " fmt -- 2.55.0.1082.g2b9226bbc0-goog
