[PATCH 7/8] PCI: hv: Allocate a named fwnode instead of an address-based one

From: Marc Zyngier
Date: Tue Aug 06 2019 - 10:57:54 EST


To allocate its fwnode that is then used to allocate an irqdomain,
the driver uses irq_domain_alloc_fwnode(), passing it a VA as an
identifier. This is a rather bad idea, as this address ends up
published in debugfs (and we want to move away from VAs there
anyway).

Instead, let's allocate a named fwnode by using the device GUID as
an identifier. It is allegedly unique, and can be traced back to
the original device.

Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/pci/controller/pci-hyperv.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 40b625458afa..f6ed2583167a 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -2521,6 +2521,7 @@ static int hv_pci_probe(struct hv_device *hdev,
const struct hv_vmbus_device_id *dev_id)
{
struct hv_pcibus_device *hbus;
+ char *name;
int ret;

/*
@@ -2589,7 +2590,14 @@ static int hv_pci_probe(struct hv_device *hdev,
goto free_config;
}

- hbus->sysdata.fwnode = irq_domain_alloc_fwnode(hbus);
+ name = kasprintf("%pUL", &hdev->dev_instance);
+ if (!name) {
+ ret = -ENOMEM;
+ goto unmap;
+ }
+
+ hbus->sysdata.fwnode = irq_domain_alloc_named_fwnode(name);
+ kfree(name);
if (!hbus->sysdata.fwnode) {
ret = -ENOMEM;
goto unmap;
--
2.20.1