On 6/11/2025 4:06 PM, Michael Kelley wrote: > From: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx> Sent: Tuesday, June 10, 2025 4:52 PM >> >> From: Mukesh Rathor <mrathor@xxxxxxxxxxxxxxxxxxx> > > The patch Subject line is confusing to me. Perhaps this better captures > the intent: > > "PCI: hv: Don't load the driver for the root partition on a bare-metal hypervisor" > Thanks, that does make more sense. >> >> init_hv_pci_drv() is not relevant for root partition on baremetal as there >> is no vmbus. On nested (with a Windows L1 root), vmbus is present. > > This needs more precision. init_hv_pci_drv() isn't what is > "not relevant". It's the entire driver that doesn't need to be loaded > because the root partition on a bare-metal hypervisor doesn't use > VMBus. It's only when the root partition is running on a nested > hypervisor that it uses VMBus, and hence may need the Hyper-V > PCI driver to be loaded. > I'll update it so it is clearer, thanks. >> >> Signed-off-by: Mukesh Rathor <mrathor@xxxxxxxxxxxxxxxxxxx> >> Signed-off-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx> >> --- >> drivers/pci/controller/pci-hyperv.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c >> index b4f29ee75848..4d25754dfe2f 100644 >> --- a/drivers/pci/controller/pci-hyperv.c >> +++ b/drivers/pci/controller/pci-hyperv.c >> @@ -4150,6 +4150,9 @@ static int __init init_hv_pci_drv(void) >> if (!hv_is_hyperv_initialized()) >> return -ENODEV; >> >> + if (hv_root_partition() && !hv_nested) >> + return -ENODEV; >> + >> ret = hv_pci_irqchip_init(); >> if (ret) >> return ret; >> -- >> 2.34.1
