Re: [PATCH net-next 10/12] net: hns3: Add handling of MAC tunnel interruption

From: Neil Horman
Date: Fri Apr 19 2019 - 14:36:40 EST


On Fri, Apr 19, 2019 at 11:05:45AM +0800, Huazhong Tan wrote:
> From: Weihang Li <liweihang@xxxxxxxxxxxxx>
>
> MAC tnl interruptions are different from other type of RAS and MSI-X
> errors, because some bits, such as OVF/LR/RF will occur during link up
> and down.
>
> The drivers should clear status of all MAC tnl interruption bits but
> shouldn't print any message that would mislead the users.
>
> In case that link down and re-up in a short time because of some reasons,
> we record when they occurred, and users can query them by debugfs.
>
> Signed-off-by: Weihang Li <liweihang@xxxxxxxxxxxxx>
> Signed-off-by: Peng Li <lipeng321@xxxxxxxxxx>
> ---
><snip>>
> bool en)
> {
> @@ -1611,6 +1636,7 @@ pci_ers_result_t hclge_handle_hw_ras_error(struct hnae3_ae_dev *ae_dev)
> int hclge_handle_hw_msix_error(struct hclge_dev *hdev,
> unsigned long *reset_requests)
> {
> + struct hclge_mac_tnl_stats mac_tnl_stats;
> struct device *dev = &hdev->pdev->dev;
> u32 mpf_bd_num, pf_bd_num, bd_num;
> enum hnae3_reset_type reset_level;
> @@ -1745,6 +1771,31 @@ int hclge_handle_hw_msix_error(struct hclge_dev *hdev,
> set_bit(HNAE3_GLOBAL_RESET, reset_requests);
> }
>
> + /* query and clear mac tnl interruptions */
> + hclge_cmd_setup_basic_desc(&desc[0], HCLGE_OPC_QUERY_MAC_TNL_INT,
> + true);
> + ret = hclge_cmd_send(&hdev->hw, &desc[0], 1);
Is this running in interrupt context ever? I don't think it is, but the
function name makes me think otherwise. If it is, this could be unsafe as you
take a spinlock in hclge_cmd_send, which is protected against bottom halves, but
not interrupts. That could cause a deadlock if there is a path to get here
directly from an interrupt context.
Neil