Re: [PATCH for-rc] RDMA/hns: Fix the double unlock problem of poll_sem

[Jason Gunthorpe <jgg@nvidia.com>]

On Mon, Aug 02, 2021 at 02:56:14PM +0800, Wenpeng Liang wrote:
> From: Yangyang Li <liyangyang20@huawei.com>
> 
> If hns_roce_cmd_use_events() fails then it means that the poll_sem is not
> obtained, but the poll_sem is released in hns_roce_cmd_use_polling(), this
> will cause an unlock problem.
> 
> This is the static checker warning:
> 	drivers/infiniband/hw/hns/hns_roce_main.c:926 hns_roce_init()
> 	error: double unlocked '&hr_dev->cmd.poll_sem' (orig line 879)
> 
> Event mode and polling mode are mutually exclusive and resources are
> separated, so there is no need to process polling mode resources in
> event mode.
> 
> The initial mode of cmd is polling mode, so even if cmd fails to switch to
> event mode, it is not necessary to switch to polling mode.
> 
> Fixes: a389d016c030 ("RDMA/hns: Enable all CMDQ context")
> Fixes: 3d50503b3b33 ("RDMA/hns: Optimize cmd init and mode selection for hip08")
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Signed-off-by: Yangyang Li <liyangyang20@huawei.com>
> Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> ---
>  drivers/infiniband/hw/hns/hns_roce_cmd.c  | 7 +++----
>  drivers/infiniband/hw/hns/hns_roce_main.c | 4 +---
>  2 files changed, 4 insertions(+), 7 deletions(-)

Applied to for-rc, thanks

Jason