diff options
| author | Peter Ujfalusi <peter.ujfalusi@ti.com> | 2017-09-21 14:35:32 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-18 09:35:38 +0200 |
| commit | 9d9c2884da2c5b458aaad5b2080a9ac31858ea9c (patch) | |
| tree | 6a9831ee9535e3988410e85127af36a624c7c27e /drivers/dma | |
| parent | 618c786d2bbacbb802c6e9c9b629f9adc21e00bf (diff) | |
dmaengine: ti-dma-crossbar: Fix possible race condition with dma_inuse
commit 2ccb4837c938357233a0b8818e3ca3e58242c952 upstream.
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.
Fixes: ec9bfa1e1a796 ("dmaengine: ti-dma-crossbar: dra7: Use bitops instead of idr")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/ti-dma-crossbar.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/dma/ti-dma-crossbar.c b/drivers/dma/ti-dma-crossbar.c index 2403475a37cf..88a00d06def6 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]; |