On Wed, 18 Dec 2019 13:25:42 +0100, Jia-Ju Bai wrote:

The driver may sleep while holding a read lock. The function call path (from bottom to top) in Linux 4.19 is:

sound/pci/ice1712/quartet.c, 414:     mutex_lock in reg_write sound/pci/ice1712/quartet.c, 485:     reg_write in set_cpld sound/pci/ice1712/quartet.c, 876:     set_cpld in qtet_set_rate sound/pci/ice1712/ice1724.c, 687:     (FUNC_PTR) qtet_set_rate in snd_vt1724_set_pro_rate sound/pci/ice1712/ice1724.c, 668:     _raw_spin_lock_irqsave in snd_vt1724_set_pro_rate

(FUNC_PTR) means a function pointer is called. mutex_lock() can sleep at runtime.

I am not sure how to properly fix this possible bug, so I only report it.

This bug is found by a static analysis tool STCheck written by myself.

Thanks for the report. I'll submitted the fix.

Takashi