Re: [PATCH v5 9/9] bus: mhi: core: Do not clear channel context more than once

From: Manivannan Sadhasivam
Date: Thu Jan 21 2021 - 10:17:45 EST


On Fri, Jan 08, 2021 at 12:54:57PM -0800, Bhaumik Bhatt wrote:
> When clearing the channel context, calling mhi_free_coherent()
> more than once can result in kernel warnings such as "trying to
> free invalid coherent area". Prevent extra work by adding a check
> to skip calling mhi_deinit_chan_ctxt() if the client driver has
> already disabled the channels.
>

Again, please explain where and when exactly you spotted this issue.

Thanks,
Mani

> Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
> ---
> 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);
>
> --
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