Re: FW: spinlocks dont work

[Jamie Lokier]

RANDAZZO@xxxxxxxxxxx wrote:
> Note the following example:
> 
> driver 'A' calls spin_lock_irqsave and gets through (but does not call
> ..unlock).
> driver 'B' calls spin_lock_irqsave and gets through???
> 
> How can B get through if A did not unlock yet?

Is that code from B an interrupt handler?
If yes, then A should have called spin_lock_irqsave()

Otherwise, is that code from B a softirq or tasklet or timer handler?
If yes, then A should have called spin_lock_bh()

Otherwise, that code from B cannot run unless you are calling
schedule() from A after taking the lock, which is a bug in your code.

-- Jamie
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