bnxt_en: delay pci_alloc_irq_vectors() in the AER path

JIRA: https://issues.redhat.com/browse/RHEL-76568

commit c2d20a3
Author: Kashyap Desai <kashyap.desai@broadcom.com>
Date:   Mon Apr 28 15:59:00 2025 -0700

    bnxt_en: delay pci_alloc_irq_vectors() in the AER path

    This patch is similar to the last patch to delay the
    pci_alloc_irq_vectors() call in the AER path until after calling
    bnxt_reserve_rings().  bnxt_reserve_rings() needs to properly map
    the MSIX table first before we call pci_alloc_irq_vectors() which
    may immediately write to the MSIX table in some architectures.

    Move the bnxt_init_int_mode() call from bnxt_io_slot_reset() to
    bnxt_io_resume() after calling bnxt_reserve_rings().

    With this change, the AER path may call bnxt_open() ->
    bnxt_hwrm_if_change() with bp->irq_tbl set to NULL.  bp->irq_tbl is
    cleared when we call bnxt_clear_int_mode() in bnxt_io_slot_reset().
    So we cannot use !bp->irq_tbl to detect aborted FW reset.  Add a
    new BNXT_FW_RESET_STATE_ABORT to detect aborted FW reset in
    bnxt_hwrm_if_change().

    Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
    Signed-off-by: Michael Chan <michael.chan@broadcom.com>
    Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Shruti Parab <shruti.parab@broadcom.com>

Author: Shruti Parab

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

@@ -12197,12 +12197,15 @@ static int bnxt_hwrm_if_change(struct bnxt *bp, bool up)
 {
 	struct hwrm_func_drv_if_change_output *resp;
 	struct hwrm_func_drv_if_change_input *req;
-	bool fw_reset = !bp->irq_tbl;
 	bool resc_reinit = false;
 	bool caps_change = false;
 	int rc, retry = 0;
+	bool fw_reset;
 	u32 flags = 0;
 
+	fw_reset = (bp->fw_reset_state == BNXT_FW_RESET_STATE_ABORT);
+	bp->fw_reset_state = 0;
+
 	if (!(bp->fw_cap & BNXT_FW_CAP_IF_CHANGE))
 		return 0;
 
@@ -14704,7 +14707,7 @@ static void bnxt_fw_reset_abort(struct bnxt *bp, int rc)
 	clear_bit(BNXT_STATE_IN_FW_RESET, &bp->state);
 	if (bp->fw_reset_state != BNXT_FW_RESET_STATE_POLL_VF)
 		bnxt_dl_health_fw_status_update(bp, false);
-	bp->fw_reset_state = 0;
+	bp->fw_reset_state = BNXT_FW_RESET_STATE_ABORT;
 	dev_close(bp->dev);
 }
 
@@ -16787,10 +16790,9 @@ static pci_ers_result_t bnxt_io_slot_reset(struct pci_dev *pdev)
 		if (!err)
 			result = PCI_ERS_RESULT_RECOVERED;
 
+		/* IRQ will be initialized later in bnxt_io_resume */
 		bnxt_ulp_irq_stop(bp);
 		bnxt_clear_int_mode(bp);
-		err = bnxt_init_int_mode(bp);
-		bnxt_ulp_irq_restart(bp, err);
 	}
 
 reset_exit:
@@ -16819,10 +16821,13 @@ static void bnxt_io_resume(struct pci_dev *pdev)
 
 	err = bnxt_hwrm_func_qcaps(bp);
 	if (!err) {
-		if (netif_running(netdev))
+		if (netif_running(netdev)) {
 			err = bnxt_open(netdev);
-		else
+		} else {
 			err = bnxt_reserve_rings(bp, true);
+			if (!err)
+				err = bnxt_init_int_mode(bp);
+		}
 	}
 
 	if (!err)

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -2609,6 +2609,7 @@ struct bnxt {
 #define BNXT_FW_RESET_STATE_POLL_FW	4
 #define BNXT_FW_RESET_STATE_OPENING	5
 #define BNXT_FW_RESET_STATE_POLL_FW_DOWN	6
+#define BNXT_FW_RESET_STATE_ABORT	7
 
 	u16			fw_reset_min_dsecs;
 #define BNXT_DFLT_FW_RST_MIN_DSECS	20