diff options
| author | Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> | 2020-08-21 09:14:23 +0530 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-08-25 16:45:17 +0530 |
| commit | 6d6018fc30bee67290dbed2fa51123f7c6f3d691 (patch) | |
| tree | 3fde22c2dded4988d680350eb3fe3121b886524c | |
| parent | 05655541c9503bfd01af4e6cbd7f5a29ac748e6c (diff) | |
| download | linux-6d6018fc30bee67290dbed2fa51123f7c6f3d691.tar.bz2 | |
drivers/dma/dma-jz4780: Fix race condition between probe and irq handler
In probe, IRQ is requested before zchan->id is initialized which can be
read in the irq handler. Hence, shift request irq after other initializations
complete.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20200821034423.12713-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/dma/dma-jz4780.c | 38 |
1 files changed, 19 insertions, 19 deletions
diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c index 448f663da89c..8beed91428bd 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -879,24 +879,11 @@ static int jz4780_dma_probe(struct platform_device *pdev) return -EINVAL; } - ret = platform_get_irq(pdev, 0); - if (ret < 0) - return ret; - - jzdma->irq = ret; - - ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev), - jzdma); - if (ret) { - dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); - return ret; - } - jzdma->clk = devm_clk_get(dev, NULL); if (IS_ERR(jzdma->clk)) { dev_err(dev, "failed to get clock\n"); ret = PTR_ERR(jzdma->clk); - goto err_free_irq; + return ret; } clk_prepare_enable(jzdma->clk); @@ -949,10 +936,23 @@ static int jz4780_dma_probe(struct platform_device *pdev) jzchan->vchan.desc_free = jz4780_dma_desc_free; } + ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto err_disable_clk; + + jzdma->irq = ret; + + ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev), + jzdma); + if (ret) { + dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); + goto err_disable_clk; + } + ret = dmaenginem_async_device_register(dd); if (ret) { dev_err(dev, "failed to register device\n"); - goto err_disable_clk; + goto err_free_irq; } /* Register with OF DMA helpers. */ @@ -960,17 +960,17 @@ static int jz4780_dma_probe(struct platform_device *pdev) jzdma); if (ret) { dev_err(dev, "failed to register OF DMA controller\n"); - goto err_disable_clk; + goto err_free_irq; } dev_info(dev, "JZ4780 DMA controller initialised\n"); return 0; -err_disable_clk: - clk_disable_unprepare(jzdma->clk); - err_free_irq: free_irq(jzdma->irq, jzdma); + +err_disable_clk: + clk_disable_unprepare(jzdma->clk); return ret; } |