Impossible OS Docs
BlackBox Diagnostic Artifacts (X:\Diag\)
The kernel writes structured diagnostic artifacts to the BlackBox service
partition (X:\Diag\) during late boot (Phase 3, after VFS + IXFS mount and
the BlackBox partition is up). They are offline-triage records: a developer or
support engineer can read them without a running registry or a live debugger.
Every writer is best-effort and degrades to a klog line if the partition is
unavailable; a missing file is never fatal.
Producers are wired in src/kernel/main/boot_desktop.c at the desktop-ready
diagnostics-dump point unless noted otherwise.
| Artifact | Producer | Contents |
|---|---|---|
boot-loader-identity.txt |
boot_loader_identity_dump_to_blackbox() (boot_version.c) |
Healthy-boot bootloader build identity: git_sha (40-hex), build_unix_time (decimal + ISO-8601), build_label. All-zero git_sha renders unavailable (the ABI no-loader sentinel), never a fake commit. |
boot-load-status.txt |
boot_load_status_dump_to_blackbox() (boot_load_status.c) |
Per-subsystem boot load/status log (ntbtlog parity): one line per subsystem (LOADED/SKIPPED/FAILED/DEGRADED, class, name, err, post, start_ms, duration_ms) with a N recorded / 64 cap, D dropped [TRUNCATED] header. |
boot-proto-fault.txt |
boot_version_blackbox_transcribe() (boot_version.c) |
Conditional: only when the prior boot halted on a boot-protocol ABI fault. Transcribes the NVRAM fault record (observed/expected magic, version, size, loader identity), then clears the NVRAM slot. |
..\Crash\last-panic.txt |
panic_evidence_write_blackbox() (panic.c) |
Conditional: only when the previous boot crashed. The cross-boot panic evidence restored from the 0x80000 page: STOP code, RIP/RSP/RFLAGS, cr2/cr3, fault vector, boot stages + last klog. (Lives under X:\Crash\, not X:\Diag\.) |
..\Perf\boot-timeline.json |
boot_timeline_dump_json() (boot_progress.c) |
Per-stage boot timeline: stage/phase/post/start_ms/duration_ms/target_ms/source(fpdt|tsc)/unreliable. (Lives under X:\Perf\, not X:\Diag\; <klog_dir> fallback when BlackBox is absent.) Wire format: boot-timeline-schema.md. |
attestation.json |
tpm_attest_report_export() (tpm_attest_report.c) |
TPM-rooted boot attestation report: manifest sha256, handoff provenance, SHA-256-quoted PCR bank, TPM2_Quote + AK pub + EK cert, trust-status fields. |
tpm-events.json |
tpm_evlog_export_cel() (tpm.c) |
Parsed TCG measured-boot event log (CEL-JSON subset). |
firmware-tables.json |
firmware-tables writer (firmware_tables_json.c) |
ACPI/SMBIOS firmware-table inventory + conformance profile; generated_at_utc from the loader build time. |
firmware-advisor.json |
firmware advisor (firmware_advisor.c) |
Firmware quirk / advisory findings. |
..\Perf\boot-trend.json |
boot_trend_publish_json() (boot_trend.c) |
Rolling boot-perf regression file: up to 16 entries of boot_seq/unix_time/phase_durations_ms, newest first, with a 3-run median growth alarm. (Lives under X:\Perf\, not X:\Diag\.) Wire format: boot-trend-schema.md. |
boot-health.json |
boot_health_publish_json() (boot_health.c) |
Consolidated boot-health dashboard: degraded caps and subsystems, missing capabilities, perf-budget breaches, MAT W^X violations, active firmware quirks, recent boot times, Secure Boot state (owner TODO-29). Wire format: boot-health-schema.md. |
entropy.json |
entropy_publish_json() (entropy_registry.c) |
Early-entropy / seed diagnostics (owner TODO-12). |
lvfs-metadata.json |
(not kernel-written) input cache read by firmware_advisor_init() -> fa_read_cache_text() (firmware_advisor.c) |
Offline LVFS firmware metadata cache the advisor CONSUMES; staged onto X:\Diag out-of-band, not produced by a boot writer. |
boot-reserved.json |
boot_reserved_blackbox_dump() |
Physical ranges the PMM kept reserved at boot. |
hwdump.txt |
hw_dump_write_file() |
Hardware inventory (PCI / ACPI / CPU). |
Adding a new
X:\Diag\artifact: add its producer to the late-boot dump sequence inboot_desktop.cand a row here in the same commit.
lvfs-metadata.jsonis the one row that is an INPUT, not a kernel-written output: the firmware advisor reads it as an offline cache. It is listed here so a developer browsingX:\Diag\knows what wrote (or, here, what reads) it.