On Sun, 06 Aug 2023 11:25:11 +0800, Duoming Zhou wrote:
> The synchronize_irq(c->irq) will not return until the IRQ handler
> mtk_uart_apdma_irq_handler() is completed. If the synchronize_irq()
> holds a spin_lock and waits the IRQ handler to complete, but the
> IRQ handler also needs the same spin_lock. The deadlock will happen.
> The process is shown below:
>
> cpu0 cpu1
> mtk_uart_apdma_device_pause() | mtk_uart_apdma_irq_handler()
> spin_lock_irqsave() |
> | spin_lock_irqsave()
> //hold the lock to wait |
> synchronize_irq() |
>
> [...]
Applied, thanks!
[1/1] dmaengine: mediatek: Fix deadlock caused by synchronize_irq()
commit: 01f1ae2733e2bb4de92fefcea5fda847d92aede1
Best regards,
--
~Vinod
