On Tue, 2011-01-25 at 17:36 +0200, Ahmed S. Darwish wrote: > The complete __roadblock__ I'm currently facing though is restoring the disk > controllers to the state originally setup by the BIOS Power-on self-test (POST). > I hope such re-initialization is even technically feasible. > > Without such re-initialization, we'll just be risking the BIOS code exploding. > That was the case in the 5-minute hang described in the cover sheet (PATCH #0). So this is the bit that's not really technically feasible. BIOS tends to run storage devices in a very primitive way (so it takes basic settings, for example and sets the device up for one particular channel of access). When preparing the device for an operating system, we have to blow away all the bios stuff and put it into a more generally performant mode (this isn't just the storage per se, it's also the interrupt and routing). Unfortunately, currently, we don't bother to save the settings the BIOS was using, so there's no way to reinitialise the device back to bios without an effective reboot. Most BIOS doesn't seem to contain storage re-POST code that's usable (it's all embedded in the boot sequence). James -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
