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 Reviewed-by: Pranjal Shrivastava Reviewed-by: Samiullah Khawaja Signed-off-by: David Matlack --- drivers/pci/liveupdate.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/pci/liveupdate.c b/drivers/pci/liveupdate.c index df6a02240aa4..a067632e70d1 100644 --- a/drivers/pci/liveupdate.c +++ b/drivers/pci/liveupdate.c @@ -70,6 +70,22 @@ * preserved. These may be relaxed in the future: * * * The device cannot be a Virtual Function (VF). + * + * Driver Binding + * ============== + * + * In the outgoing kernel, it is the driver's responsibility to ensure that it + * does not release a device between pci_liveupdate_preserve() and + * pci_liveupdate_unpreserve(). + * + * In the incoming kernel, it is the driver's responsibility to 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. i.e. 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. This may change in the future. */ #define pr_fmt(fmt) "PCI: " KBUILD_BASENAME ": " fmt -- 2.55.0.795.g602f6c329a-goog