| Message ID | 1612470486-10440-9-git-send-email-bbhatt@codeaurora.org |
|---|---|
| State | New |
| Headers | show |
| Series | Updates to MHI channel handling | expand |
On 2/4/21 12:28 PM, 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@codeaurora.org> Reviewed-by: Hemant Kumar <hemantk@codeaurora.org> -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
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@codeaurora.org> 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 >
On 2021-02-24 02:10 AM, Manivannan Sadhasivam wrote: > 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@codeaurora.org> > > Is this patch still valid? We merged a similar fix from Loic for v5.11. > Yes, both the patches work to solve the same problem. This one just does it sooner and relies on internal state variable rather than context being NULL. > 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 >> Thanks, Bhaumik --- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
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);
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@codeaurora.org> --- drivers/bus/mhi/core/init.c | 1 + 1 file changed, 1 insertion(+)