On Tue, Dec 12, 2017 at 2:24 AM, Jia-Ju Bai <baijiaju1...@163.com> wrote: > According to sound/soc/samsung/pcm.c, the kernel module may sleep under a > spinlock. > The function call path is: > s3c_pcm_hw_params (acquire the spinlock) > clk_get_rate > clk_core_get_rate > clk_prepare_lock > mutex_lock --> may sleep > > I do not find a good way to fix it, so I only report. > This possible bug is found by my static analysis tool (DSAC) and my code > review.
Thanks for the report. Your finding looks correct, the code might sleep under spinlock. I do not see easy solution. Maybe the readl(regs + S3C_PCM_CLKCTL) and clk_get_rate() could be moved before spinlock. The second path modifying it - s3c_pcm_set_sysclk() - is not protected by it. The spinlock is not effective around it. Best regards, Krzysztof
