> https://bugzilla.kernel.org/show_bug.cgi?id=41722 This system boots Windows fine, but hangs when Linux does an outb(0x142e) to enable ACPI mode. Len suggests that this enters SMM mode, where the BIOS does stuff which we basically cannot debug. Len did hazard a guess that MTRR config is a possible difference between Linux and Windows. I think we can figure out the Linux MTRR config from the dmesg of a boot with "acpi=off". Rogério, would you mind attaching that log here (it's OK if you need to apply the transparent bridge reversion patch). Then, since I think you do have Windows on the box, can you use a free trial version of AIDA64 (http://www.aida64.com/) to collect a complete system report and attach that as well? With luck, we can extract the MTRR config under Windows from that. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html