[PATCH net 0/2] net: mana: Fix debugfs directory naming and file lifecycle

[PATCH net 0/2] net: mana: Fix debugfs directory naming and file lifecycle

[Erni Sri Satya Vennela]

This series fixes two pre-existing debugfs issues in the MANA driver.

Patch 1 fixes the per-device debugfs directory naming to use the unique
PCI BDF address via pci_name(), avoiding a potential NULL pointer
dereference when pdev->slot is NULL (e.g. VFIO passthrough, nested KVM)
and preventing name collisions across multiple PFs or VFs.

Patch 2 moves the current_speed debugfs file creation from
mana_probe_port() to mana_init_port() so it survives detach/attach
cycles triggered by MTU changes or XDP program changes.

Erni Sri Satya Vennela (2):
  net: mana: Use pci_name() for debugfs directory naming
  net: mana: Move current_speed debugfs file to mana_init_port()

 drivers/net/ethernet/microsoft/mana/gdma_main.c | 7 ++-----
 drivers/net/ethernet/microsoft/mana/mana_en.c   | 4 ++--
 2 files changed, 4 insertions(+), 7 deletions(-)

-- 
2.34.1

[PATCH net 1/2] 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@linux.microsoft.com>
---
 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

Re: [PATCH net 1/2] net: mana: Use pci_name() for debugfs directory naming

[Simon Horman]

On Wed, Apr 08, 2026 at 01:12:19AM -0700, Erni Sri Satya Vennela wrote:
> 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@linux.microsoft.com>

Reviewed-by: Simon Horman <horms@kernel.org>

[PATCH net 2/2] net: mana: Move current_speed debugfs file to mana_init_port()

[Erni Sri Satya Vennela]

Move the current_speed debugfs file creation from mana_probe_port() to
mana_init_port(). The file was previously created only during initial
probe, but mana_cleanup_port_context() removes the entire vPort debugfs
directory during detach/attach cycles. Since mana_init_port() recreates
the directory on re-attach, moving current_speed here ensures it survives
these cycles.

Fixes: 75cabb46935b ("net: mana: Add support for net_shaper_ops")
Signed-off-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>
---
 drivers/net/ethernet/microsoft/mana/mana_en.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 07630322545f..6302432b9bf6 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -3154,6 +3154,8 @@ static int mana_init_port(struct net_device *ndev)
 	eth_hw_addr_set(ndev, apc->mac_addr);
 	sprintf(vport, "vport%d", port_idx);
 	apc->mana_port_debugfs = debugfs_create_dir(vport, gc->mana_pci_debugfs);
+	debugfs_create_u32("current_speed", 0400, apc->mana_port_debugfs,
+			   &apc->speed);
 	return 0;
 
 reset_apc:
@@ -3432,8 +3434,6 @@ static int mana_probe_port(struct mana_context *ac, int port_idx,
 
 	netif_carrier_on(ndev);
 
-	debugfs_create_u32("current_speed", 0400, apc->mana_port_debugfs, &apc->speed);
-
 	return 0;
 
 free_indir:
-- 
2.34.1

Re: [PATCH net 2/2] net: mana: Move current_speed debugfs file to mana_init_port()

[Simon Horman]

On Wed, Apr 08, 2026 at 01:12:20AM -0700, Erni Sri Satya Vennela wrote:
> Move the current_speed debugfs file creation from mana_probe_port() to
> mana_init_port(). The file was previously created only during initial
> probe, but mana_cleanup_port_context() removes the entire vPort debugfs
> directory during detach/attach cycles. Since mana_init_port() recreates
> the directory on re-attach, moving current_speed here ensures it survives
> these cycles.
> 
> Fixes: 75cabb46935b ("net: mana: Add support for net_shaper_ops")
> Signed-off-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [PATCH net 0/2] net: mana: Fix debugfs directory naming and file lifecycle

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Wed,  8 Apr 2026 01:12:18 -0700 you wrote:
> This series fixes two pre-existing debugfs issues in the MANA driver.
> 
> Patch 1 fixes the per-device debugfs directory naming to use the unique
> PCI BDF address via pci_name(), avoiding a potential NULL pointer
> dereference when pdev->slot is NULL (e.g. VFIO passthrough, nested KVM)
> and preventing name collisions across multiple PFs or VFs.
> 
> [...]

Here is the summary with links:
  - [net,1/2] net: mana: Use pci_name() for debugfs directory naming
    https://git.kernel.org/netdev/net/c/c116f07ab9d2
  - [net,2/2] net: mana: Move current_speed debugfs file to mana_init_port()
    https://git.kernel.org/netdev/net/c/3b7c7fc97aea

You are awesome, thank you!
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