17 December 2021. Summary of changes for version 20211217:
This release is available at https://acpica.org/downloads
1) ACPICA kernel-resident subsystem:
Hardware: Do not flush CPU cache when entering S4 and S5. According to ACPI 6.4, Section 16.2, the CPU cache flushing is required on entering to S1, S2, and S3, but the ACPICA code flushes the CPU cache regardless of the sleep state. Blind cache flush on entering S5 causes problems for TDX.
Avoid subobject buffer overflow when validating RSDP signature. Since the Signature member is accessed through an ACPI_TABLE_HEADER, the pointer to it is only to a 4-char array, and so trying to read past the 4th character, as will be done when it is an RSDP, reads beyond the bounds of the accessed member. Contributed by jrtc27.
Add support for PCC Opregion special context data. PCC Opregion added in ACPIC 6.3 requires special context data similar to GPIO and Generic Serial Bus as it needs to know the internal PCC buffer and its length as well as the PCC channel index when the opregion handler is being executed by the OSPM. Adds support for the special context data needed by PCC Opregion. Submitted by Sudeep Holla
2) iASL Compiler/Disassembler and ACPICA tools:
iASL: Completed compiler support for the NHLT ACPI table.
iASL/NHLT table: Fixed a reported problem where a fault would occur during disassembly of a "Linux-Specific" section if the "Specific Data" part was not present.
iASL: Added full support (compiler and disassembler) for the AGDI ACPI table. Contributed by: Ilkka Koskinen .
iASL: Added full support for the TDEL ACPI table.
iASL table compiler: FADT support updates:
1) Allow the 32-bit DSDT address to be zero.
2) Issue error if both the 32-bit and 64-bit DSDT addresses are zero.
iASL: Fix unaligned accesses to local cache allocations. Contributed by jrtc27.
iASL: Open binary input files in binary mode, not text mode Affects binary input AML files, as well as binary data table files, for disassembly.