Looking at you acpi-enabled GENERIC.MP dmesg, there are a lot of scary messages:
> acpimadt0: unknown apic structure type ff > acpimadt0: unknown apic structure type ff > acpimadt0: unknown apic structure type ff > acpi device at acpi0 from table OEMB not configured > acpi device at acpi0 from table SRAT not configured > acpiprt0 at acpi0: bus 0 (PCI0) > acpiprt1 at acpi0: bus 7 (P0P1) > acpiprt2 at acpi0: bus 0 (PCIB) > acpiprt3 at acpi0: bus 0 (POGA) > acpiprt3: no apic found for irq 73 > acpiprt3: no apic found for irq 74 > acpiprt3: no apic found for irq 75 > acpiprt3: no apic found for irq 72 > acpiprt3: no apic found for irq 75 > acpiprt4 at acpi0: bus 0 (POGB) > acpiprt4: no apic found for irq 80 > acpiprt4: no apic found for irq 81 > acpiprt4: no apic found for irq 82 > acpiprt4: no apic found for irq 79 > acpiprt4: no apic found for irq 81 > acpiprt4: no apic found for irq 82 > acpiprt4: no apic found for irq 79 > acpiprt4: no apic found for irq 80 > acpiprt4: no apic found for irq 82 > acpiprt4: no apic found for irq 79 > acpiprt4: no apic found for irq 80 > acpiprt4: no apic found for irq 81 Can you run # acpidump -o WTF2V028 > WTF2V028.acpidump and send me all the files it generates? Also, you may want to try a 4.2-current kernel. At least one acpi bug that affects your machine has been fixed recently. Mark
