[tip: irq/core] PCI: hv: Allocate a named fwnode instead of an address-based one

[tip-bot2 for Marc Zyngier]

The following commit has been merged into the irq/core branch of tip:

Commit-ID:     467a3bb974320a23c0c000559cc54b64e06e9787
Gitweb:        https://git.kernel.org/tip/467a3bb974320a23c0c000559cc54b64e06e9787
Author:        Marc Zyngier <maz@xxxxxxxxxx>
AuthorDate:    Tue, 06 Aug 2019 15:23:33 +01:00
Committer:     Marc Zyngier <maz@xxxxxxxxxx>
CommitterDate: Wed, 07 Aug 2019 14:24:49 +01:00

PCI: hv: Allocate a named fwnode instead of an address-based one

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.

Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
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 40b6254..97056f3 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(GFP_KERNEL, "%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;