From 81cc6edc08705ac0146fe6ac14a0982a31ce6f3d Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Thu, 21 May 2015 09:34:09 +0900 Subject: [PATCH 1/2] dmaengine: pl330: Fix hang on dmaengine_terminate_all on certain boards The pl330 device could hang infinitely on certain boards when DMA channels are terminated. It was caused by lack of runtime resume when executing pl330_terminate_all() which calls the _stop() function. _stop() accesses device register and can loop infinitely while checking for device state. The hang was confirmed by Dinh Nguyen on Altera SOCFPGA Cyclone V board during boot. It can be also triggered with: $ echo 1 > /sys/module/dmatest/parameters/iterations $ echo dma1chan0 > /sys/module/dmatest/parameters/channel $ echo 1 > /sys/module/dmatest/parameters/run $ sleep 1 $ cat /sys/module/dmatest/parameters/run Reported-by: Dinh Nguyen Signed-off-by: Krzysztof Kozlowski Fixes: ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12") Cc: Tested-by: Dinh Nguyen Signed-off-by: Vinod Koul --- drivers/dma/pl330.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index a7d9d3029b14..340f9e607cd8 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2127,6 +2127,7 @@ static int pl330_terminate_all(struct dma_chan *chan) struct pl330_dmac *pl330 = pch->dmac; LIST_HEAD(list); + pm_runtime_get_sync(pl330->ddma.dev); spin_lock_irqsave(&pch->lock, flags); spin_lock(&pl330->lock); _stop(pch->thread); @@ -2151,6 +2152,8 @@ static int pl330_terminate_all(struct dma_chan *chan) list_splice_tail_init(&pch->work_list, &pl330->desc_pool); list_splice_tail_init(&pch->completed_list, &pl330->desc_pool); spin_unlock_irqrestore(&pch->lock, flags); + pm_runtime_mark_last_busy(pl330->ddma.dev); + pm_runtime_put_autosuspend(pl330->ddma.dev); return 0; } From 429770823d961187c39df490d49683c467b10065 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Tue, 26 May 2015 13:11:28 +0300 Subject: [PATCH 2/2] dmaengine: hsu: Fix memory leak when stopping a running transfer The vd->node is removed from the lists when the transfer started so the vchan_get_all_descriptors() will not find it. This results memory leak. Signed-off-by: Peter Ujfalusi [andy: fix the typo to prevent a compilation error] Signed-off-by: Andy Shevchenko Signed-off-by: Vinod Koul --- drivers/dma/hsu/hsu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/dma/hsu/hsu.c b/drivers/dma/hsu/hsu.c index 9b84def7a353..f42f71e37e73 100644 --- a/drivers/dma/hsu/hsu.c +++ b/drivers/dma/hsu/hsu.c @@ -384,7 +384,10 @@ static int hsu_dma_terminate_all(struct dma_chan *chan) spin_lock_irqsave(&hsuc->vchan.lock, flags); hsu_dma_stop_channel(hsuc); - hsuc->desc = NULL; + if (hsuc->desc) { + hsu_dma_desc_free(&hsuc->desc->vdesc); + hsuc->desc = NULL; + } vchan_get_all_descriptors(&hsuc->vchan, &head); spin_unlock_irqrestore(&hsuc->vchan.lock, flags);