| From 05ee66bb789cd990a807b5dc45fcf22af8aca4df Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Sat, 19 Mar 2022 10:21:42 +0800 |
| Subject: dmaengine: mediatek:Fix PM usage reference leak of |
| mtk_uart_apdma_alloc_chan_resources |
| |
| From: zhangqilong <zhangqilong3@huawei.com> |
| |
| [ Upstream commit 545b2baac89b859180e51215468c05d85ea8465a ] |
| |
| pm_runtime_get_sync will increment pm usage counter even it failed. |
| Forgetting to putting operation will result in reference leak here. |
| We fix it: |
| 1) Replacing it with pm_runtime_resume_and_get to keep usage counter |
| balanced. |
| 2) Add putting operation before returning error. |
| |
| Fixes:9135408c3ace4 ("dmaengine: mediatek: Add MediaTek UART APDMA support") |
| Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com> |
| Link: https://lore.kernel.org/r/20220319022142.142709-1-zhangqilong3@huawei.com |
| Signed-off-by: Vinod Koul <vkoul@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/dma/mediatek/mtk-uart-apdma.c | 9 ++++++--- |
| 1 file changed, 6 insertions(+), 3 deletions(-) |
| |
| diff --git a/drivers/dma/mediatek/mtk-uart-apdma.c b/drivers/dma/mediatek/mtk-uart-apdma.c |
| index 9c0ea13ca788..7718d09e3d29 100644 |
| --- a/drivers/dma/mediatek/mtk-uart-apdma.c |
| +++ b/drivers/dma/mediatek/mtk-uart-apdma.c |
| @@ -274,7 +274,7 @@ static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan) |
| unsigned int status; |
| int ret; |
| |
| - ret = pm_runtime_get_sync(mtkd->ddev.dev); |
| + ret = pm_runtime_resume_and_get(mtkd->ddev.dev); |
| if (ret < 0) { |
| pm_runtime_put_noidle(chan->device->dev); |
| return ret; |
| @@ -288,18 +288,21 @@ static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan) |
| ret = readx_poll_timeout(readl, c->base + VFF_EN, |
| status, !status, 10, 100); |
| if (ret) |
| - return ret; |
| + goto err_pm; |
| |
| ret = request_irq(c->irq, mtk_uart_apdma_irq_handler, |
| IRQF_TRIGGER_NONE, KBUILD_MODNAME, chan); |
| if (ret < 0) { |
| dev_err(chan->device->dev, "Can't request dma IRQ\n"); |
| - return -EINVAL; |
| + ret = -EINVAL; |
| + goto err_pm; |
| } |
| |
| if (mtkd->support_33bits) |
| mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_CLR_B); |
| |
| +err_pm: |
| + pm_runtime_put_noidle(mtkd->ddev.dev); |
| return ret; |
| } |
| |
| -- |
| 2.35.1 |
| |