Messages in this thread | | | Date | Sun, 3 Apr 2022 00:13:55 +0300 | Subject | Re: staging: r8188eu: how to handle nested mutex under spinlock | From | Pavel Skripkin <> |
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Hi Michael,
On 4/2/22 23:47, Michael Straube wrote: > 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? >
I've looked into this like a month ago.
IMO, this code just need to be redesigned, since locking scheme is very complicated there and, as smatch says, not correct.
Simple s/mutex_lock/spin_lock/ may work in that case, but one day locking scheme should be reworked... Or just some code parts should be dropped :))
With regards, Pavel Skripkin
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