On 2021-02-10 12:25 AM, Manivannan Sadhasivam wrote:
From: Loic Poulain <loic.poulain@xxxxxxxxxx>
mhi_deinit_chan_ctxt functionthat takes care of unitializing channel
s/functionthat/function that, uninitializing
resources, including unmapping coherent MHI areas, can be called
from different path in case of controller unregistering/removal:
- From a client driver remove callback, via mhi_unprepare_channel
- From mhi_driver_remove that unitialize all channels
uninitialize
mhi_driver_remove()
|-> driver->remove()
| |-> mhi_unprepare_channel()
| |-> mhi_deinit_chan_ctxt()
|...
|-> mhi_deinit_chan_ctxt()
This leads to double dma freeing...
Fix that by preventing deinit for already uninitialized channel.
Fixes: a7f422f2f89e ("bus: mhi: Fix channel close issue on driver
remove")
Signed-off-by: Loic Poulain <loic.poulain@xxxxxxxxxx>
Reported-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Tested-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Link:
https://lore.kernel.org/r/1612894264-15956-1-git-send-email-loic.poulain@xxxxxxxxxx
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/bus/mhi/core/init.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index aa575d3fb3ae..be4eebb0971b 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -557,6 +557,9 @@ void mhi_deinit_chan_ctxt(struct mhi_controller
*mhi_cntrl,
tre_ring = &mhi_chan->tre_ring;
chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan];
+ if (!chan_ctxt->rbase) /* Already uninitialized */
+ return;
+
mhi_free_coherent(mhi_cntrl, tre_ring->alloc_size,
tre_ring->pre_aligned, tre_ring->dma_handle);
vfree(buf_ring->base);
As mentioned in my previous email, I see some improvements can be made
to the commit
message and title of this patch. Highlighted those above.
Please update title to "bus: mhi: core: Fix double DMA free from
mhi_deinit_chan_ctxt()".
Thanks,
Bhaumik
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