[PATCH net-next v5 1/3] net: mana: Use pci_name() for debugfs directory naming

[Erni Sri Satya Vennela]

Use pci_name(pdev) for the per-device debugfs directory instead of
hardcoded "0" for PFs and pci_slot_name(pdev->slot) for VFs. The
previous approach had two issues:

1. pci_slot_name() dereferences pdev->slot, which can be NULL for VFs
   in environments like generic VFIO passthrough or nested KVM,
   causing a NULL pointer dereference.

2. Multiple PFs would all use "0", and VFs across different PCI
   domains or buses could share the same slot name, leading to
   -EEXIST errors from debugfs_create_dir().

pci_name(pdev) returns the unique BDF address, is always valid, and
is unique across the system.

Fixes: 6607c17c6c5e ("net: mana: Enable debugfs files for MANA device")
Signed-off-by: Erni Sri Satya Vennela <ernis@xxxxxxxxxxxxxxxxxxx>
---
Changes in v5:
* New to patchset.
Changes in v4, v3, v2:
* Not created
---
 drivers/net/ethernet/microsoft/mana/gdma_main.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/gdma_main.c b/drivers/net/ethernet/microsoft/mana/gdma_main.c
index 43741cd35af8..098fbda0d128 100644
--- a/drivers/net/ethernet/microsoft/mana/gdma_main.c
+++ b/drivers/net/ethernet/microsoft/mana/gdma_main.c
@@ -2065,11 +2065,8 @@ static int mana_gd_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	gc->dev = &pdev->dev;
 	xa_init(&gc->irq_contexts);
 
-	if (gc->is_pf)
-		gc->mana_pci_debugfs = debugfs_create_dir("0", mana_debugfs_root);
-	else
-		gc->mana_pci_debugfs = debugfs_create_dir(pci_slot_name(pdev->slot),
-							  mana_debugfs_root);
+	gc->mana_pci_debugfs = debugfs_create_dir(pci_name(pdev),
+						  mana_debugfs_root);
 
 	err = mana_gd_setup(pdev);
 	if (err)
-- 
2.34.1