[PATCH] bnxt_en: Add parameter disable_vf_bind

[PATCH] bnxt_en: Add parameter disable_vf_bind

[Deli Zhang]

In virtualization, VF is usually not bound by native drivers, instead
should be passthrough to VM. Most PF and VF drivers provide separate
names, e.g. "igb" and "igbvf", so that the hypervisor can control
whether to use VF devices locally. The "bnxt_en" driver is a special
case, it can drive both PF and VF devices, so here add a parameter
"disable_vf_bind" to allow users to control.

Signed-off-by: Deli Zhang <deli.zhang21th@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 41 +++++++++++++++++++++--
 1 file changed, 39 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 2cb3185c442c..89897182a71d 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -88,6 +88,12 @@ MODULE_DESCRIPTION("Broadcom NetXtreme network driver");
 
 #define BNXT_TX_PUSH_THRESH 164
 
+#ifdef CONFIG_BNXT_SRIOV
+static bool disable_vf_bind;
+module_param(disable_vf_bind, bool, 0);
+MODULE_PARM_DESC(disable_vf_bind, "Whether to disable binding to virtual functions (VFs)");
+#endif
+
 /* indexed by enum board_idx */
 static const struct {
 	char *name;
@@ -144,7 +150,12 @@ static const struct {
 	[NETXTREME_E_P7_VF] = { "Broadcom BCM5760X Virtual Function" },
 };
 
-static const struct pci_device_id bnxt_pci_tbl[] = {
+/* The boundary between PF and VF devices in bnxt_pci_tbl */
+#ifdef CONFIG_BNXT_SRIOV
+#define FIRST_VF_DEV_ID 0x1606
+#endif
+
+static struct pci_device_id bnxt_pci_tbl[] = {
 	{ PCI_VDEVICE(BROADCOM, 0x1604), .driver_data = BCM5745x_NPAR },
 	{ PCI_VDEVICE(BROADCOM, 0x1605), .driver_data = BCM5745x_NPAR },
 	{ PCI_VDEVICE(BROADCOM, 0x1614), .driver_data = BCM57454 },
@@ -196,7 +207,7 @@ static const struct pci_device_id bnxt_pci_tbl[] = {
 	{ PCI_VDEVICE(BROADCOM, 0xd802), .driver_data = BCM58802 },
 	{ PCI_VDEVICE(BROADCOM, 0xd804), .driver_data = BCM58804 },
 #ifdef CONFIG_BNXT_SRIOV
-	{ PCI_VDEVICE(BROADCOM, 0x1606), .driver_data = NETXTREME_E_VF },
+	{ PCI_VDEVICE(BROADCOM, FIRST_VF_DEV_ID), .driver_data = NETXTREME_E_VF },
 	{ PCI_VDEVICE(BROADCOM, 0x1607), .driver_data = NETXTREME_E_VF_HV },
 	{ PCI_VDEVICE(BROADCOM, 0x1608), .driver_data = NETXTREME_E_VF_HV },
 	{ PCI_VDEVICE(BROADCOM, 0x1609), .driver_data = NETXTREME_E_VF },
@@ -17129,10 +17140,36 @@ static struct pci_driver bnxt_pci_driver = {
 #endif
 };
 
+#ifdef CONFIG_BNXT_SRIOV
+static void bnxt_vf_bind_init(void)
+{
+	s32 idx;
+
+	if (!disable_vf_bind)
+		return;
+
+	for (idx = 0; bnxt_pci_tbl[idx].device != 0; idx++) {
+		if (bnxt_pci_tbl[idx].device == FIRST_VF_DEV_ID) {
+			/* Truncate off VF devices */
+			memset(&bnxt_pci_tbl[idx], 0, sizeof(struct pci_device_id));
+			pr_info("%s: Disabled VF binding, id table offset %u",
+				DRV_MODULE_NAME, idx);
+			return;
+		}
+	}
+
+	/* Should not reach here! */
+	pr_crit("%s: Unknown VF dev id %u", DRV_MODULE_NAME, FIRST_VF_DEV_ID);
+}
+#endif
+
 static int __init bnxt_init(void)
 {
 	int err;
 
+#ifdef CONFIG_BNXT_SRIOV
+	bnxt_vf_bind_init();
+#endif
 	bnxt_debug_init();
 	err = pci_register_driver(&bnxt_pci_driver);
 	if (err) {
-- 
2.47.0

Re: [PATCH] bnxt_en: Add parameter disable_vf_bind

[Pavan Chebbi]

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On Wed, Jun 25, 2025 at 11:01 AM Deli Zhang <deli.zhang21th@gmail.com> wrote:
>
> In virtualization, VF is usually not bound by native drivers, instead
> should be passthrough to VM. Most PF and VF drivers provide separate
> names, e.g. "igb" and "igbvf", so that the hypervisor can control
> whether to use VF devices locally. The "bnxt_en" driver is a special
> case, it can drive both PF and VF devices, so here add a parameter
> "disable_vf_bind" to allow users to control.

You can always unbind the driver using the sysfs interface, right?
Besides, module params are not acceptable.

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Re: [PATCH] bnxt_en: Add parameter disable_vf_bind

[Jakub Kicinski]

On Wed, 25 Jun 2025 13:30:05 +0800 Deli Zhang wrote:
> In virtualization, VF is usually not bound by native drivers, instead
> should be passthrough to VM. Most PF and VF drivers provide separate
> names, e.g. "igb" and "igbvf", so that the hypervisor can control
> whether to use VF devices locally. The "bnxt_en" driver is a special
> case, it can drive both PF and VF devices, so here add a parameter
> "disable_vf_bind" to allow users to control.

sriov_drivers_autoprobe