[PATCH 5.4 160/344] dmaengine: imx-sdma: Fix memory leak

From: Greg Kroah-Hartman
Date: Fri Feb 21 2020 - 03:08:12 EST


From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>

[ Upstream commit 02939cd167095f16328a1bd5cab5a90b550606df ]

The current descriptor is not on any list of the virtual DMA channel.
Once sdma_terminate_all() is called when a descriptor is currently
in flight then this one is forgotten to be freed. We have to call
vchan_terminate_vdesc() on this descriptor to re-add it to the lists.
Now that we also free the currently running descriptor we can (and
actually have to) remove the current descriptor from its list also
for the cyclic case.

Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
Reviewed-by: Robin Gong <yibin.gong@xxxxxxx>
Tested-by: Robin Gong <yibin.gong@xxxxxxx>
Link: https://lore.kernel.org/r/20191216105328.15198-10-s.hauer@xxxxxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/imx-sdma.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index c27e206a764c3..66f1b2ac5cde4 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -760,12 +760,8 @@ static void sdma_start_desc(struct sdma_channel *sdmac)
return;
}
sdmac->desc = desc = to_sdma_desc(&vd->tx);
- /*
- * Do not delete the node in desc_issued list in cyclic mode, otherwise
- * the desc allocated will never be freed in vchan_dma_desc_free_list
- */
- if (!(sdmac->flags & IMX_DMA_SG_LOOP))
- list_del(&vd->node);
+
+ list_del(&vd->node);

sdma->channel_control[channel].base_bd_ptr = desc->bd_phys;
sdma->channel_control[channel].current_bd_ptr = desc->bd_phys;
@@ -1071,7 +1067,6 @@ static void sdma_channel_terminate_work(struct work_struct *work)

spin_lock_irqsave(&sdmac->vc.lock, flags);
vchan_get_all_descriptors(&sdmac->vc, &head);
- sdmac->desc = NULL;
spin_unlock_irqrestore(&sdmac->vc.lock, flags);
vchan_dma_desc_free_list(&sdmac->vc, &head);
sdmac->context_loaded = false;
@@ -1080,11 +1075,19 @@ static void sdma_channel_terminate_work(struct work_struct *work)
static int sdma_disable_channel_async(struct dma_chan *chan)
{
struct sdma_channel *sdmac = to_sdma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&sdmac->vc.lock, flags);

sdma_disable_channel(chan);

- if (sdmac->desc)
+ if (sdmac->desc) {
+ vchan_terminate_vdesc(&sdmac->desc->vd);
+ sdmac->desc = NULL;
schedule_work(&sdmac->terminate_worker);
+ }
+
+ spin_unlock_irqrestore(&sdmac->vc.lock, flags);

return 0;
}
--
2.20.1