[PATCH iwl-net v2] idpf: check error for register_netdev() on init

[PATCH iwl-net v2] idpf: check error for register_netdev() on init

[Emil Tantilov]

Current init logic ignores the error code from register_netdev(),
which will cause WARN_ON() on attempt to unregister it, if there was one,
and there is no info for the user that the creation of the netdev failed.

WARNING: CPU: 89 PID: 6902 at net/core/dev.c:11512 unregister_netdevice_many_notify+0x211/0x1a10
...
[ 3707.563641]  unregister_netdev+0x1c/0x30
[ 3707.563656]  idpf_vport_dealloc+0x5cf/0xce0 [idpf]
[ 3707.563684]  idpf_deinit_task+0xef/0x160 [idpf]
[ 3707.563712]  idpf_vc_core_deinit+0x84/0x320 [idpf]
[ 3707.563739]  idpf_remove+0xbf/0x780 [idpf]
[ 3707.563769]  pci_device_remove+0xab/0x1e0
[ 3707.563786]  device_release_driver_internal+0x371/0x530
[ 3707.563803]  driver_detach+0xbf/0x180
[ 3707.563816]  bus_remove_driver+0x11b/0x2a0
[ 3707.563829]  pci_unregister_driver+0x2a/0x250

Introduce an error check and log the vport number and error code.
On removal make sure to check VPORT_REG_NETDEV flag prior to calling
unregister and free on the netdev.

Add local variables for idx, vport_config and netdev for readability.

Fixes: 0fe45467a104 ("idpf: add create vport and netdev configuration")
Suggested-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
---
Changelog:
v2:
- Refactored a bit to avoid >80 char lines.
- Changed the netdev and flag check to allow for early continue in the
  max_vports loop, which also helps to reduce the identation.

v1:
https://lore.kernel.org/intel-wired-lan/20250211023851.21090-1-emil.s.tantilov@intel.com/

---
 drivers/net/ethernet/intel/idpf/idpf_lib.c | 31 +++++++++++++++-------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/intel/idpf/idpf_lib.c b/drivers/net/ethernet/intel/idpf/idpf_lib.c
index a3d6b8f198a8..a055a47449f1 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_lib.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_lib.c
@@ -927,15 +927,19 @@ static int idpf_stop(struct net_device *netdev)
 static void idpf_decfg_netdev(struct idpf_vport *vport)
 {
 	struct idpf_adapter *adapter = vport->adapter;
+	u16 idx = vport->idx;
 
 	kfree(vport->rx_ptype_lkup);
 	vport->rx_ptype_lkup = NULL;
 
-	unregister_netdev(vport->netdev);
-	free_netdev(vport->netdev);
+	if (test_and_clear_bit(IDPF_VPORT_REG_NETDEV,
+			       adapter->vport_config[idx]->flags)) {
+		unregister_netdev(vport->netdev);
+		free_netdev(vport->netdev);
+	}
 	vport->netdev = NULL;
 
-	adapter->netdevs[vport->idx] = NULL;
+	adapter->netdevs[idx] = NULL;
 }
 
 /**
@@ -1536,13 +1540,22 @@ void idpf_init_task(struct work_struct *work)
 	}
 
 	for (index = 0; index < adapter->max_vports; index++) {
-		if (adapter->netdevs[index] &&
-		    !test_bit(IDPF_VPORT_REG_NETDEV,
-			      adapter->vport_config[index]->flags)) {
-			register_netdev(adapter->netdevs[index]);
-			set_bit(IDPF_VPORT_REG_NETDEV,
-				adapter->vport_config[index]->flags);
+		struct net_device *netdev = adapter->netdevs[index];
+		struct idpf_vport_config *vport_config;
+
+		vport_config = adapter->vport_config[index];
+
+		if (!netdev ||
+		    test_bit(IDPF_VPORT_REG_NETDEV, vport_config->flags))
+			continue;
+
+		err = register_netdev(netdev);
+		if (err) {
+			dev_err(&pdev->dev, "failed to register netdev for vport %d: %pe\n",
+				index, ERR_PTR(err));
+			continue;
 		}
+		set_bit(IDPF_VPORT_REG_NETDEV, vport_config->flags);
 	}
 
 	/* As all the required vports are created, clear the reset flag
-- 
2.17.2

Re: [PATCH iwl-net v2] idpf: check error for register_netdev() on init

[Simon Horman]

On Fri, Feb 14, 2025 at 09:18:16AM -0800, Emil Tantilov wrote:
> Current init logic ignores the error code from register_netdev(),
> which will cause WARN_ON() on attempt to unregister it, if there was one,
> and there is no info for the user that the creation of the netdev failed.
> 
> WARNING: CPU: 89 PID: 6902 at net/core/dev.c:11512 unregister_netdevice_many_notify+0x211/0x1a10
> ...
> [ 3707.563641]  unregister_netdev+0x1c/0x30
> [ 3707.563656]  idpf_vport_dealloc+0x5cf/0xce0 [idpf]
> [ 3707.563684]  idpf_deinit_task+0xef/0x160 [idpf]
> [ 3707.563712]  idpf_vc_core_deinit+0x84/0x320 [idpf]
> [ 3707.563739]  idpf_remove+0xbf/0x780 [idpf]
> [ 3707.563769]  pci_device_remove+0xab/0x1e0
> [ 3707.563786]  device_release_driver_internal+0x371/0x530
> [ 3707.563803]  driver_detach+0xbf/0x180
> [ 3707.563816]  bus_remove_driver+0x11b/0x2a0
> [ 3707.563829]  pci_unregister_driver+0x2a/0x250
> 
> Introduce an error check and log the vport number and error code.
> On removal make sure to check VPORT_REG_NETDEV flag prior to calling
> unregister and free on the netdev.
> 
> Add local variables for idx, vport_config and netdev for readability.
> 
> Fixes: 0fe45467a104 ("idpf: add create vport and netdev configuration")
> Suggested-by: Tony Nguyen <anthony.l.nguyen@intel.com>
> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
> ---
> Changelog:
> v2:
> - Refactored a bit to avoid >80 char lines.
> - Changed the netdev and flag check to allow for early continue in the
>   max_vports loop, which also helps to reduce the identation.
> 
> v1:
> https://lore.kernel.org/intel-wired-lan/20250211023851.21090-1-emil.s.tantilov@intel.com/

Thanks for the update.

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

RE: [Intel-wired-lan] [PATCH iwl-net v2] idpf: check error for register_netdev() on init

[Salin, Samuel]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf Of
> Simon Horman
> Sent: Monday, February 17, 2025 8:17 AM
> To: Tantilov, Emil S <emil.s.tantilov@intel.com>
> Cc: intel-wired-lan@lists.osuosl.org; netdev@vger.kernel.org;
> decot@google.com; willemb@google.com; Nguyen, Anthony L
> <anthony.l.nguyen@intel.com>; davem@davemloft.net;
> edumazet@google.com; kuba@kernel.org; pabeni@redhat.com; Chittim,
> Madhu <madhu.chittim@intel.com>; Kitszel, Przemyslaw
> <przemyslaw.kitszel@intel.com>
> Subject: Re: [Intel-wired-lan] [PATCH iwl-net v2] idpf: check error for
> register_netdev() on init
> 
> On Fri, Feb 14, 2025 at 09:18:16AM -0800, Emil Tantilov wrote:
> > Current init logic ignores the error code from register_netdev(),
> > which will cause WARN_ON() on attempt to unregister it, if there was
> > one, and there is no info for the user that the creation of the netdev failed.
> >
> > WARNING: CPU: 89 PID: 6902 at net/core/dev.c:11512
> > unregister_netdevice_many_notify+0x211/0x1a10
> > ...
> > [ 3707.563641]  unregister_netdev+0x1c/0x30 [ 3707.563656]
> > idpf_vport_dealloc+0x5cf/0xce0 [idpf] [ 3707.563684]
> > idpf_deinit_task+0xef/0x160 [idpf] [ 3707.563712]
> > idpf_vc_core_deinit+0x84/0x320 [idpf] [ 3707.563739]
> > idpf_remove+0xbf/0x780 [idpf] [ 3707.563769]
> > pci_device_remove+0xab/0x1e0 [ 3707.563786]
> > device_release_driver_internal+0x371/0x530
> > [ 3707.563803]  driver_detach+0xbf/0x180 [ 3707.563816]
> > bus_remove_driver+0x11b/0x2a0 [ 3707.563829]
> > pci_unregister_driver+0x2a/0x250
> >
> > Introduce an error check and log the vport number and error code.
> > On removal make sure to check VPORT_REG_NETDEV flag prior to calling
> > unregister and free on the netdev.
> >
> > Add local variables for idx, vport_config and netdev for readability.
> >
> > Fixes: 0fe45467a104 ("idpf: add create vport and netdev
> > configuration")
> > Suggested-by: Tony Nguyen <anthony.l.nguyen@intel.com>
> > Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
> > ---
> > Changelog:
> > v2:
> > - Refactored a bit to avoid >80 char lines.
> > - Changed the netdev and flag check to allow for early continue in the
> >   max_vports loop, which also helps to reduce the identation.
> >
> > v1:
> > https://lore.kernel.org/intel-wired-lan/20250211023851.21090-1-emil.s.
> > tantilov@intel.com/
> 
> Thanks for the update.
> 
> Reviewed-by: Simon Horman <horms@kernel.org>

Tested-by: Samuel Salin <Samuel.salin@intel.com>