Re: [PATCH v6 8/8] bus: mhi: core: Do not clear channel context more than once

[Manivannan Sadhasivam]

On Thu, Feb 04, 2021 at 12:28:06PM -0800, Bhaumik Bhatt wrote:
> Clearing a channel context can happen twice if the client driver
> unprepares and reset the channels from the remove() callback from
> a controller requested MHI power down sequence. If there are
> multiple attempts at calling the mhi_free_coherent() API, we see
> kernel warnings such as "trying to free invalid coherent area".
> Example for one such client is the QRTR MHI driver. Avoid these
> warnings by skipping mhi_deinit_chan_ctxt() API call and prevent
> extra work from MHI as the channels are already disabled.
> 
> Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>

Is this patch still valid? We merged a similar fix from Loic for v5.11.

Thanks,
Mani

> ---
>  drivers/bus/mhi/core/init.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index 30eef19..272f350 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -1314,6 +1314,7 @@ static int mhi_driver_remove(struct device *dev)
>  
>  		if ((ch_state[dir] == MHI_CH_STATE_ENABLED ||
>  		     ch_state[dir] == MHI_CH_STATE_STOP) &&
> +		    mhi_chan->ch_state != MHI_CH_STATE_DISABLED &&
>  		    !mhi_chan->offload_ch)
>  			mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan);
>  
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>