bnxt_en: fix devlink port registration to netdev

We don't register a devlink port in case of a VF so
avoid setting the devlink pointer to netdev.
Also, SET_NETDEV_DEVLINK_PORT has to be moved
so that we determine whether the device is PF/VF first.

This fixes the NULL pointer dereference of devlink_port->devlink
when creating VFs:

BUG: kernel NULL pointer dereference, address: 0000000000000160
PGD 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 14 PID: 388 Comm: kworker/14:1 Kdump: loaded Not tainted 6.1.0-rc8 #5
Hardware name: Dell Inc. PowerEdge R750/06V45N, BIOS 1.3.8 08/31/2021
Workqueue: events work_for_cpu_fn
RIP: 0010:devlink_nl_port_handle_size+0xb/0x50
Code: 83 c4 10 5b 5d c3 cc cc cc cc b8 a6 ff ff ff eb de e8 c9 59 21 00 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 53 48 8b 47 20 <48> 8b a8 60 01 00 00 48 8b 45 60 48 8b 38 e8 92 90 1a 00 48 8b 7d
RSP: 0018:ff4fe5394846fcd8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000794 RCX: 0000000000000000
RDX: ff1f129683a30a40 RSI: 0000000000000008 RDI: ff1f1296bb496188
RBP: 0000000000000334 R08: 0000000000000cc0 R09: 0000000000000000
R10: ff1f1296bb494298 R11: ffffffffffffffc0 R12: 0000000000000000
R13: 0000000000000000 R14: ff1f1296bb494000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ff1f129e5fa00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000160 CR3: 000000131f610006 CR4: 0000000000771ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 if_nlmsg_size+0x14a/0x220
 rtmsg_ifinfo_build_skb+0x3c/0x100
 rtmsg_ifinfo+0x9c/0xc0
 register_netdevice+0x59d/0x670
 register_netdev+0x1c/0x40
 bnxt_init_one+0x674/0xa60 [bnxt_en]
 local_pci_probe+0x42/0x80
 work_for_cpu_fn+0x13/0x20
 process_one_work+0x1e2/0x3b0
 ? rescuer_thread+0x390/0x390
 worker_thread+0x1c4/0x3a0
 ? rescuer_thread+0x390/0x390
 kthread+0xd6/0x100
 ? kthread_complete_and_exit+0x20/0x20

Fixes: ac73d4bf ("net: make drivers to use SET_NETDEV_DEVLINK_PORT to set devlink_port")
Cc: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Vikas Gupta <vikas.gupta@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Reviewed-by: Kalesh Anakkur Purayil <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Damodharam Ammepalli <damodharam.ammepalli@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -13591,7 +13591,6 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		return -ENOMEM;
 
 	bp = netdev_priv(dev);
-	SET_NETDEV_DEVLINK_PORT(dev, &bp->dl_port);
 	bp->board_idx = ent->driver_data;
 	bp->msg_enable = BNXT_DEF_MSG_ENABLE;
 	bnxt_set_max_func_irqs(bp, max_irqs);
@@ -13599,6 +13598,10 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (bnxt_vf_pciid(bp->board_idx))
 		bp->flags |= BNXT_FLAG_VF;
 
+	/* No devlink port registration in case of a VF */
+	if (BNXT_PF(bp))
+		SET_NETDEV_DEVLINK_PORT(dev, &bp->dl_port);
+
 	if (pdev->msix_cap)
 		bp->flags |= BNXT_FLAG_MSIX_CAP;