page fault in AcpiExReleaseMutex
One can course DF to panic if one presses a function key to turn on wifi during
early boot, putting debug.acpi.disabled="ec" in /boot/loader.conf stops the panic.
Apparently this is fixed in the upstream ACPICA, so we just need to resync
#1 Updated by eocallaghan about 6 years ago
The problem is with the AML Mutex handling function AcpiExReleaseMutex where the
function can fault under the very rare condition when the interpreter has
blocked, the interpreter lock is released, the interpreter is then reentered via
the same thread, and attempts to acquire an AML mutex that was previously acquired.
This is indeed fixed in the acpica-unix-20100806 snapshot.