Trent Piepho wrote: > On Wed, 18 Feb 2009, Oliver Endriss wrote: > > [1] If you want to lock a process against an interrupt handler, > > - the process must use spin_lock_irq() > > - the interrupt can use spin_lock() > > > > A routine has to use spin_lock_irqsave if (and only if) process and irq > > call the routine concurrently. I do not see yet how this might happen. > > Some code calls the swfilter functions from process context and some > drivers call them from interrupt context.
There would be a problem if (and only if) it could happen concurrently within a given driver. A driver may call the functions either from process context or from a tasklet/irq. User space access will occur only if demux_source == DMX_MEMORY_FE. In this case the driver must not call the routine. If demux_source == DMX_FRONTEND, the driver may call the routine, but userspace won't. Sorry, I need more information to identify the problem. CU Oliver -- ---------------------------------------------------------------- VDR Remote Plugin 0.4.0: http://www.escape-edv.de/endriss/vdr/ ---------------------------------------------------------------- -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
