[PATCH] dmaengine: ti-dma-crossbar: Fix possible race condition with dma_inuse
flat view
From: Vinod Koul <hidden>
Date: 2017-09-21 17:28:07
Also in:
linux-omap, lkml, stable
On Thu, Sep 21, 2017 at 02:35:32PM +0300, Peter Ujfalusi wrote:
When looking for unused xbar_out lane we should also protect the set_bit() call with the same mutex to protect against concurrent threads picking the same ID.
Applied, thanks Just a note, somehow the patches from you only are getting mangled for me. Curiously, the ones in patchworks are fine and I used to apply that, not sure what mail servers at our work places are doing!!
quoted hunk ↗ jump to hunk
Fixes: ec9bfa1e1a796 ("dmaengine: ti-dma-crossbar: dra7: Use bitops instead of idr") Signed-off-by: Peter Ujfalusi <redacted> Cc: stable at vger.kernel.org --- drivers/dma/ti-dma-crossbar.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/drivers/dma/ti-dma-crossbar.c b/drivers/dma/ti-dma-crossbar.c index 10ef9d5d5a66..7df910e7c348 100644 --- a/drivers/dma/ti-dma-crossbar.c +++ b/drivers/dma/ti-dma-crossbar.c@@ -262,13 +262,14 @@ static void *ti_dra7_xbar_route_allocate(struct of_phandle_args *dma_spec, mutex_lock(&xbar->mutex); map->xbar_out = find_first_zero_bit(xbar->dma_inuse, xbar->dma_requests); - mutex_unlock(&xbar->mutex); if (map->xbar_out == xbar->dma_requests) { + mutex_unlock(&xbar->mutex); dev_err(&pdev->dev, "Run out of free DMA requests\n"); kfree(map); return ERR_PTR(-ENOMEM); } set_bit(map->xbar_out, xbar->dma_inuse); + mutex_unlock(&xbar->mutex); map->xbar_in = (u16)dma_spec->args[0];-- 2.14.1 Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
-- ~Vinod