Phase A of the ACPI fork-sync plan (local/docs/ACPI-FORK-SYNC-STRATEGY-2026-06-30.md).
Restores the kernel to the upstream Redox OS kernel main branch state for
the ACPI subsystem:
- Cargo.toml: switch redox_syscall from 0.7.4 (two versions behind) to a
git ref of gitlab.redox-os.org/redox-os/syscall.git, matching the
upstream master dependency. The crates.io 0.8.1 release predates the
AcpiVerb enum that MR #613 / MR #275 introduced, so a crates.io pin
is insufficient.
- src/acpi/rsdp.rs: full rewrite to match upstream f49c7d99 (RSDP
validation + NonNull + fail-softly):
* signature check "RSD PTR "
* 20-byte base checksum
* full-length checksum for revision >= 2
* NonNull<u8> instead of *const u8
Fixes gap #1 from the 2026-06-30 ACPI assessment: the kernel was
accepting any pointer from the bootloader without validation.
- src/startup/mod.rs: acpi_rsdp() returns Option<NonNull<u8>> to match
the new Rsdp::get_rsdp signature.
- src/acpi/mod.rs: init() takes Option<NonNull<u8>>.
- src/scheme/acpi.rs: full rewrite to upstream MR #613 (Simplify acpi
scheme). Drops the /scheme/kernel.acpi/ filesystem surface in favor
of a single Fd::open + call() interface with AcpiVerb verbs:
* AcpiVerb::ReadRxsdt - returns the raw RXSDT bytes
* AcpiVerb::CheckShutdown - returns whether shutdown is pending
Uses HandleBits bitflags, atomic EXISTS_KSTOP_HANDLE, Mutex<L4> from
crate::sync::ordered. Replaces /scheme/kernel.acpi/rxsdt and
/scheme/kernel.acpi/kstop files.
- src/scheme/mod.rs: KernelScheme::kcall signature updated to take
fds: &[usize] instead of id: usize (matches upstream). kfpath now
has a default body returning EOPNOTSUPP (matches upstream).
- src/scheme/memory.rs, proc.rs, user.rs: kcall impls updated to
match new trait signature, using fds.first() to extract the single
handle for backward compat.
- src/scheme/proc.rs: kcall dispatch adds _ => Err(EINVAL) catch-all
for the new ProcSchemeVerb variants (RegsInt, RegsFloat, RegsEnv,
SchedAffinity, Start) that the gitlab syscall crate adds. These
verbs are not yet implemented in the proc scheme; the catch-all
returns EINVAL cleanly instead of failing to compile.
- src/syscall/fs.rs: SYS_CALL dispatcher now passes &[number] to
scheme.kcall() to match the new trait signature.
- Makefile: removed -Z json-target-spec flag (promoted to stable in
nightly 2026-04-01; the flag is unknown in our pinned toolchain).
Verified by `make` in local/sources/kernel/ with PATH including the
prefix cross-toolchain: kernel builds and links successfully.