On Tue, Nov 23, 2021 at 10:24:02PM +0800, Wenpeng Liang wrote:
> From: Yangyang Li <liyangyang20@xxxxxxxxxx>
>
> When hns_roce_v2_destroy_qp() is called, the brief calling process of the
> driver is as follows:
>
> ......
> hns_roce_v2_destroy_qp
> hns_roce_v2_qp_modify
> hns_roce_cmd_mbox
> hns_roce_qp_destroy
>
> If hns_roce_cmd_mbox() detects that the hardware is being reset during
> the execution of the hns_roce_cmd_mbox(), the driver will not be able
> to get the return value from the hardware (the firmware cannot respond
> to the driver's mailbox during the hardware reset phase). The driver
> needs to wait for the hardware reset to complete before continuing to
> execute hns_roce_qp_destroy(), otherwise it may happen that the driver
> releases the resources but the hardware is still accessing. In order to
> fix this problem, HNS RoCE needs to add a piece of code to wait for the
> hardware reset to complete.
>
> The original interface get_hw_reset_stat() is the instantaneous state
> of the hardware reset, which cannot accurately reflect whether the
> hardware reset is completed, so it needs to be replaced with the
> ae_dev_reset_cnt interface.
>
> The sign that the hardware reset is complete is that the return value
> of the ae_dev_reset_cnt interface is greater than the original value
> reset_cnt recorded by the driver.
>
> Fixes: 6a04aed6afae ("RDMA/hns: Fix the chip hanging caused by sending mailbox&CMQ during reset")
> Signed-off-by: Yangyang Li <liyangyang20@xxxxxxxxxx>
> Signed-off-by: Wenpeng Liang <liangwenpeng@xxxxxxxxxx>
> ---
> drivers/infiniband/hw/hns/hns_roce_hw_v2.c | 12 +++++++++++-
> 1 file changed, 11 insertions(+), 1 deletion(-)
Applied to for-rc, thanks
Jason
