Cert storage expanded from the old 16-byte placeholder to a real
32-byte seed + 32-byte pubkey. vm_zuse_cert_install() now has a
kernel-side duplicate in src/starkernel/vm/vm_core.c -- the kernel
build's VM_EXCLUDE list drops src/vm.c entirely (same reason
vm_set_base() already has two independent copies), so the hosted-only
version added earlier this session was never actually linked into the
kernel. FORTH-side ZUSE-CERT-LO@/HI@ replaced with ZUSE-PUBKEY@ (i -- u)
over the public half only; ACL-ZUSE-BOOT now checks
ZUSE-CERT-INSTALLED? before authenticating instead of unconditionally.
Attempted NVRAM-based persistence (GetVariable/SetVariable) for the
first-boot mint flow: page-faulted inside OVMF's variable service
(CR2 in the flash MMIO window). Moving the call site to match the one
proven-safe existing SetVariable call site in this codebase produced
the identical crash -- not a timing issue. Localized with debug
markers (one boot): GetVariable works; SetVariable with real data
never returns. The existing "working" precedent call is actually a
delete-of-nonexistent-variable (size=0, data=NULL), a cheaper path
that never touches flash, so it proved nothing about real writes.
Root cause: this kernel's VMM never maps the region OVMF's variable
service needs for real flash writes -- a genuine gap in UEFI runtime-
services support, not Zuse-specific, and not obviously fixable in a
3-arch-uniform way (flash window location is firmware/arch-specific).
Independently, storing the raw seed in RUNTIME_ACCESS NVRAM would have
been a real security defect regardless of the crash -- readable by any
later-loaded UEFI app or the booted OS.
Reverted to a known-safe state: all NVRAM/mint code removed from
kernel_main.c, init.4th's ACL.4th line back to its documented
commented-out default. Verified clean compile and clean boot on all
three architectures. Cert storage expansion (the part that works)
stays. A dedicated system-identity disk (virtio-blk, already proven
for writes via Artemis) is the recommended next substrate -- not yet
decided or built. Full investigation documented in FABRIC-3.md.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U14ET9CWAtbQMbYqomKgXd
Punch list §25 item 0.3 NOT complete.
- Added `starkernel/fdt.h` and `fdt.c` for minimal read-only devicetree parsing: sufficient for boot-time lookups such as `timebase-frequency`.
- Bootloader now captures the devicetree blob (DTB) from `EFI_DTB_TABLE_GUID` into `BootInfo::dtb`.
- RISC-V timer subsystem now uses the `time` CSR as the primary timestamp source, abandoning the hardcoded `cycle` frequency assumption.
- Timer rate is read from `timebase-frequency` in the DTB when accessible; otherwise, a fallback value is used with a RELATIVE trust level.
- Integrated the SBI TIME extension for one-shot timer deadlines, ensuring re-arming occurs after each tick to avoid missing heartbeats.
Verified: riscv64 builds clean, boots to the ok> prompt with no regression; `riscv64/timer.c` reports accurate frequencies on QEMU's default firmware.
Signed-off-by: Robert Allan James <robert.allan.james@gmail.com>