staging: r8188eu: how to handle nested mutex under spinlock

From: Michael Straube
Date: Sat Apr 02 2022 - 16:47:47 EST


Hi all,

smatch reported a sleeping in atomic context.

rtw_set_802_11_disassociate() <- disables preempt
-> _rtw_pwr_wakeup()
-> ips_leave()

rtw_set_802_11_disassociate() takes a spinlock and ips_leave() uses a
mutex.

I'm fairly new to the locking stuff, but as far as I know this is not a
false positive since mutex can sleep, but that's not allowed under a
spinlock.

What is the best way to handle this?
I'm not sure if converting the mutex to a spinlock (including all the
other places where the mutex is used) is the right thing to do?

thanks,
Michael