Re: kern/38035: repeatable kernel lock spinout

[yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi)]

> Kernel lock error: _kernel_lock: spinout
> 
> with a backtrace of:
> 
> _kernel_lock()
> _intr_biglock_wrapper()
> DDB lost frame ... trying...
> Xintr_ioapic_level11
> --interrupt frame--
> _kernel_lock
> biodone2
> biointr
> softint_dispatch
> ...

a backtrace of the interrupted lwp might be interesting.

> other cpu:
> __cpu_simple_lock()

i guess the interrupted lwp is holding this lock.
if so, making it a spin mutex with IPL_VM (or an adaptive mutex if its safe)
is a usual solution.

> rf_DiskReadFuncForTheads()

rf_DiskReadFuncForThreads ?

YAMAMOTO Takashi

> FireNode()
> FireNodeList()
> rf_FinishNode()
> rf_NullNodeFunc()
> FireNode()
> rf_DispatchDAG()
> rf_VerifyParityRAID1()
> rf_RewriteParity()
> rf_RewriteParityThread()
> 
> >How-To-Repeat:
> on my machine, rebooting with dirty raid parity does it
> 
> >Fix:
> n/a