From 5ca9e7ce6eebec53362ff779264143860ccf68cd Mon Sep 17 00:00:00 2001 From: Petr Kulhavy Date: Fri, 27 Mar 2015 13:35:51 +0200 Subject: [PATCH] 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 Signed-off-by: Peter Ujfalusi CC: CC: Signed-off-by: Vinod Koul --- drivers/dma/edma.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c index 276157f22612..53dbd3b3384c 100644 --- a/drivers/dma/edma.c +++ b/drivers/dma/edma.c @@ -260,6 +260,13 @@ static int edma_terminate_all(struct dma_chan *chan) */ if (echan->edesc) { 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; edma_stop(echan->ch_num); /* Move the cyclic channel back to default queue */