On Sun, 28 Oct 2012, Roland Stigge wrote: > > consider arch/arm/mach-lpc32xx/irq.c: irq_set_chained_handler() is > called at a point where it accesses > irq_to_desc(IRQ_LPC32XX_SUB2IRQ)->irq_data.hwirq but which is not yet > initialized.
None of the functions which are called inside of irq_set_chained_handler() touches desc->irq_data.hwirq. So what are you talking about? I just had a look into that lpc32xx irq code. At the end of lpc32xx_init_irq(): irq_base = irq_alloc_descs(-1, 0, NR_IRQS, 0); if (irq_base < 0) { pr_warn("Cannot allocate irq_descs, assuming pre-allocated\n"); irq_base = 0; } That's just hilarious. Of course are the interrupts preallocated, simply because machine_desc->nr_irqs is 0 and therefor the ARM core code allocates NR_IRQS irq descriptors in the early setup way before lpc32xx_init_irq() is called. If those interrupts would not be preallocated, then the code would fail to initialize any interrupt at all. And of course nothing would notice as all function calls to set_irq_* do not check the return value. That brilliant thing came in via commit f5c42271 (ARM: LPC32xx: Device tree support). I have no idea from where you copied that and why you thought putting it at the end of the init function would be a good idea. Though, that has nothing todo with your problem description above. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/