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On Mon, 21 Nov 2005, Matthew Wilcox wrote: >> On Mon, Nov 21, 2005 at 10:55:24AM -0800, Linus Torvalds wrote: > > Quite frankly, if we change [PCI_]NO_IRQ to -1, there's almost certainly > > going to be a lot of drivers breaking.> > There's only one driver using NO_IRQ today (outside of architectures > which define NO_IRQ to -1, that is). So *this* series of patches should > break nothing. Right. But the point is that most drivers will do something like if (!dev->irq) return; (whatever, made up). And that having NO_IRQ be anything but 0 is thus fundamentally broken. Because the fact is, NO_IRQ _is_ zero. And exactly because it's zero, and that is encoded everywhere, nobody uses it. > That's a common misreading of the PCI spec -- it actually says the > opposite. I'm NOT talking about PCI specs. I'm talking about real hardware. Read pretty much _any_ data-sheet for an interrupt router, and you'll see that the bit pattern 0000 means _disabled_. In other words, I'm talking about HARD REALITY. I know, it's a bitch. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
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