qed: Limit msix vectors in kdump kernel to the minimum required count.

[ Upstream commit bb7858ba1102f82470a917e041fd23e6385c31be ]

Memory size is limited in the kdump kernel environment. Allocation of more
msix-vectors (or queues) consumes few tens of MBs of memory, which might
lead to the kdump kernel failure.
This patch adds changes to limit the number of MSI-X vectors in kdump
kernel to minimum required value (i.e., 2 per engine).

Fixes: fe56b9e6a ("qed: Add module with basic common support")
Signed-off-by: Sudarsana Reddy Kalluru <Sudarsana.Kalluru@cavium.com>
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/qlogic/qed/qed_main.c b/drivers/net/ethernet/qlogic/qed/qed_main.c
index 27832885a87fdb6614d4d646d5ae25e45a253f8a..2c958921dfb36f876594b6b0f7f22d67628731fb 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed_main.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_main.c
@@ -779,6 +779,14 @@ static int qed_slowpath_setup_int(struct qed_dev *cdev,
        /* We want a minimum of one slowpath and one fastpath vector per hwfn */
        cdev->int_params.in.min_msix_cnt = cdev->num_hwfns * 2;
 
+       if (is_kdump_kernel()) {
+               DP_INFO(cdev,
+                       "Kdump kernel: Limit the max number of requested MSI-X vectors to %hd\n",
+                       cdev->int_params.in.min_msix_cnt);
+               cdev->int_params.in.num_vectors =
+                       cdev->int_params.in.min_msix_cnt;
+       }
+
        rc = qed_set_int_mode(cdev, false);
        if (rc)  {
                DP_ERR(cdev, "qed_slowpath_setup_int ERR\n");