Hi!
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:
- Replacing it with pm_runtime_resume_and_get to keep usage counter balanced.
Suspect.
- Add putting operation before returning error.
Yes but you also put in success case, which is likely wrong. mtk_uart_apdma_free_chan_resources() does second put.
+++ 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;
This is suspect, too. What is the put_noidle doing there? Seems like it was meant to undo the get_sync operation, but uses different argument?
@@ -288,18 +288,21 @@ static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan) 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;
}
This should only be done in error case.
Best regards, Pavel