dmaengine: edma: fix memory leak when terminating running transfers

If edma_terminate_all() was called while a transfer was running (i.e. after
edma_execute() but before edma_callback()) the echan->edesc was not freed.

This was due to the fact that a running transfer is on none of the
vchan lists: desc_submitted, desc_issued, desc_completed (edma_execute()
removes it from the desc_issued list), so the vchan_dma_desc_free_list()
called at the end of edma_terminate_all() didn't find it and didn't free it.

This bug was found on an AM1808 based hardware (very similar to da850evm,
however using the second MMC/SD controller), where intense operations on the SD
card wasted the device 128MB RAM within a couple of days.

Peter Ujfalusi:
The issue is even more severe since it affects cyclic (audio) transfers as
well. In this case starting/stopping audio will results memory leak.

Signed-off-by: Petr Kulhavy <petr@barix.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
CC: <stable@vger.kernel.org>
CC: <linux-omap@vger.kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Petr Kulhavy 2015-03-27 13:35:51 +02:00 committed by Vinod Koul
parent ca76683930
commit 5ca9e7ce6e

View File

@ -260,6 +260,13 @@ static int edma_terminate_all(struct dma_chan *chan)
*/ */
if (echan->edesc) { if (echan->edesc) {
int cyclic = echan->edesc->cyclic; int cyclic = echan->edesc->cyclic;
/*
* free the running request descriptor
* since it is not in any of the vdesc lists
*/
edma_desc_free(&echan->edesc->vdesc);
echan->edesc = NULL; echan->edesc = NULL;
edma_stop(echan->ch_num); edma_stop(echan->ch_num);
/* Move the cyclic channel back to default queue */ /* Move the cyclic channel back to default queue */