* * *
XXX: The internal memory tracking of ACPICA, available when
ACPI_DBG_TRACK_ALLOCATIONS is defined, has been removed
from ACPI_DEBUG.
This is due to the instability of the ABI of ACPICA.
If the memory tracking is enabled, ACPICA will insert a header
to each memory allocation. As a consequence, when ACPI specific
code is loaded as a kernel module and the running kernel has
been compiled with ACPI_DEBUG, the result is an instant panic.
This happens because of unaligned memory access when the code
tries to use ACPI_FREE for a buffer obtained via ACPI_ALLOCATE,
AcpiEvaluateObject(), and related calls.
If the involved memory statistics are required, a separate constant
ACPI_DEBUG_ALLOC is available in options(4) for ACPI_DEBUG kernels.
* * *
Discussed with, and ok'ed by, jmcneill@ and pooka@.
cd85adf1c0