From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guennadi Liakhovetski Subject: [PATCH 1/2] dmaengine: nbpfaxi: fix a theoretical race Date: Sun, 3 Aug 2014 19:13:03 +0200 (CEST) Message-ID: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Vinod Koul , "Shevchenko, Andriy" , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Grant Likely , Rob Herring , Phil Edworthy , Arnd Bergmann List-Id: devicetree@vger.kernel.org A race possibility exists if a DMA slave driver tries to free channel resources witout waiting for all transfers to complete and without explicitly terminating all requests. In such a case the IRQ processing thread can race with .device_free_chan_resources(). To fix this race empty all descriptor lists before freeing descriptor cache. Signed-off-by: Guennadi Liakhovetski --- drivers/dma/nbpfaxi.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/dma/nbpfaxi.c b/drivers/dma/nbpfaxi.c index 77c5a89..5b40ac8 100644 --- a/drivers/dma/nbpfaxi.c +++ b/drivers/dma/nbpfaxi.c @@ -1054,6 +1054,7 @@ static void nbpf_free_chan_resources(struct dma_chan *dchan) dev_dbg(dchan->device->dev, "Entry %s()\n", __func__); nbpf_chan_halt(chan); + nbpf_chan_idle(chan); /* Clean up for if a channel is re-used for MEMCPY after slave DMA */ nbpf_chan_prepare_default(chan); -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html