The Handle::Config read handler never returned 0, so fs::read /
read_to_end on /scheme/pci/<addr>/config streamed dwords forever —
any unbounded read of a config file hung. Found by the initfs
driver-manager hang: propose_msix_vectors' unbounded config read never
terminated, stalling the oneshot initfs service and the whole boot.
- cfg_access: Pcie::has_ecam() reports ECAM availability.
- scheme: config_space_size() = 4096 with ECAM, 256 in PCI 3.0
fallback; the read handler returns Ok(0) at the boundary and fstat
advertises the correct size.
- fallback.rs: config reads at offset >= 256 (PCIe extended space) now
return the PCI-standard 0xFFFFFFFF 'absent' value and writes are
dropped, instead of panicking the PCI daemon. This is the exact
behavior of real hardware and Linux's CF8 path on MCFG-less machines,
and it lets MSI-X feature discovery degrade to INTx cleanly. Found by
the first driver-manager QEMU gate (i440fx): pcid panicked at
fallback.rs:65 and the boot hung.
- driver_handler.rs: drop vestigial func param from read_full_device_id.
- driver_interface/mod.rs: use Option::insert's return value directly
(must_use) instead of discarding and re-reading as_ref.
An extended-capability walk (pci_types capabilities()) that follows a
chain running to/past the end of config space read at offset 4096,
which tripped the dword-offset assert in bus_addr_offset_in_dwords
("pcie offset larger than 4095") and aborted pcid with an Invalid
opcode fault / UNHANDLED EXCEPTION on boot — after switchroot to /usr,
so it blocked reaching login.
PCIe config space is exactly 4096 bytes (offsets 0..=4095). Fix at two
levels:
- ConfigRegionAccess::read/write (cfg_access/mod.rs): guard the single
access choke point — an out-of-range read returns the PCI "no
response" pattern (0xFFFFFFFF, which also terminates a capability
walk cleanly) and an out-of-range write is a no-op. This catches any
caller (capability walk, scheme reads, driver access).
- scheme.rs config read/write loop: clamp the loop bound with
saturating_add(...).min(4096) so a consumer requesting offset+len
past the boundary reads only the valid part instead of looping to
offset 4096.
Verified: boot no longer panics in pcid (progresses past the previous
crash point through switchroot and the /usr driver set).
The pcid_interface crate now reads the two env vars emitted by
driver-manager's SpawnDecision committee:
- REDBEAR_DRIVER_PCI_IRQ_MODE: lets the spawned child know
whether to fall back to MSI / INTx instead of MSI-X
- REDBEAR_DRIVER_DISABLE_ACCEL: lets the spawned child suppress
hardware acceleration (matches PciQuirkFlags::DISABLE_ACCEL)
Both values are stored on PciFunctionHandle and exposed via
accessors (irq_mode_hint / disable_accel_hint) so the driver
daemons can read them at startup. 6 new unit tests cover the
env-var parsing.
Refs: local/docs/DRIVER-MANAGER-MIGRATION-PLAN.md § 5.2 D2.7.
- try_mem now returns Result (matching caller expectations)
- try_map_bar: non-panicking BAR mapping on PciFunctionHandle
- try_pci_allocate_interrupt_vector: non-panicking IRQ allocation
- virtio-core: reverted .ok_or() back to .map_err() for Result type
Added try_mem() returning Option<(usize, usize)> for non-panicking
memory BAR access. Fixed virtio-core/probe.rs to use .ok_or() instead
of .map_err() to match the Option return type.
Per local/docs/PATCH-PRESERVATION-AUDIT-2026-07-12.md the base
fork was carrying only 38 of 100 patches in local/patches/base/.
The other 62 patches' content was silently missing from the fork
working tree, even though their .patch files were preserved.
This commit re-applies 41 patches that genuinely still apply
cleanly + 17 hunks that partially applied. Recovery covers:
- D-Bus initfs service wiring (P4-initfs-dbus-services)
- USB service wiring (P4-initfs-usb-drm-services)
- netcfg/dhcp/dhcpv6 driver fixes
- acpid shutdown/PM/quirk fixes
- inputd/ps2d hard-fail logging
- pcid driver interface refinements (server cmd channel)
- virtio-core for VirtualBox support
- ixgbed/rtl8139/rtl8168 net drivers
- ahcid NCQ + per-function interrupt coalescing
- logd persistent logging
- bootstrap procmgr race-condition fixes
- cargo version pin to +rb0.3.0 (synchronized release branch)
58 files changed, +1444/-318 lines.
Untracked mnt/ tree and *.orig / *.rej files cleaned up after
patch application (leftover from absolute-path patch headers).
This way PCI drivers don't need to use the privileged physmap interface,
but only need access to a pcid handle. This is not yet enough for
running drivers as unprivileged processes. Interrupts also need
privileges and we need IOMMU support in the kernel.
Red Bear OS