[BUG] ALSA: ice1712: a possible sleep-in-atomic-context bug in snd_vt1724_set_pro_rate()

From: Jia-Ju Bai
Date: Wed Dec 18 2019 - 07:25:45 EST


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


Best wishes,
Jia-Ju Bai