Hi, After some discussion on IRC I was about to file a bug on the kernel, but I'm still not convinced if that's appropiate, as there are various ways to tackle this. So, please, give me your opinion on this.
I found that some very critical cmdline options for booting aren't honoured anymore (I have an old computer that will exhibit various problems because of incorrect dma detection with recent kernels). I could finally dig that this is because drivers/ide/ide.c goes into a module in default debian kernels, and modules don't read cmdline. Now I found that the solution is very simple, adding the option as if the module was loaded post-init and then running update-initramfs. But I find this very non-obvious, and not very nice if you cannot boot. I had to read kernel code to find out what source file was responsible of this, to find that it is a module in Debian, then understanding that initramfs just copies /etc/modules.d and uses it. Maybe I'm a dummy, but I needed to do all that. I couldn't find anywhere in the net something describing all this process, but lots of references to the standard way of passing options from grub/lilo. To make things more confusing, when I installed, somehow I didn't have DMA problems. I think I deducted from the isolinux help that I could use ide-core.ide=nodma. A idiom that doesn't work with the installed kernel+initramfs. So, this could be handled by various ways: - Putting notices in relevant places so that everybody can understand what's happening (release notes, FAQs, package documentation..) - Compiling with CONFIG_BLK_DEV_IDE=y (Ubuntu does this) - Using Kyle McMartin's recent proposed patch [0] that enables modules to read cmdline. - Adding more intelligence to initramfs to detect this options and pass them to the correct module (I think it already does this for a couple of options), or using the same syntax as d-i (this seems easy to add, although it differs from historic usage). Thoughts? [0] http://lkml.org/lkml/2007/4/18/212 -- Martín Ferrari
