Critical: kernel_ref() UB eliminated
- kernel_ref() returned &'static mut, creating aliasing mutable
references across trap handler + boot code (13+ call sites)
- Replaced with kernel_ptr() -> *mut Kernel, each use site does
explicit unsafe { &mut *kernel_ptr() }
- KernelCell: removed get_mut(), added as_ptr() -> *mut T
- UB is gone: raw pointer access makes the single-core invariant
explicit at every use site
Important: process cleanup on exit/fault
- New destroy_process() method consolidates cleanup:
- Removes all threads from scheduler and endpoints
- Clears pending messages and results
- Destroys process and frees ProcessMemory
- handle_exit and handle_fault both use destroy_process()
- handle_exit_thread uses destroy_process when last thread exits
IPC hardening:
- Added invariant comment on pending_messages[sender].take()
(sender in wait queue must have a pending message)
handle_release_pages:
- Now uses translate_va to convert VA→PA (was treating VA as PA)
Complete microkernel boot pipeline: adapter loads only init + storage + display
from disk. Init bootstraps all other servers by reading binaries from the
storage server via IPC, parsing ELF, creating processes, mapping pages, and
spawning threads.
New syscalls:
- CreateEndpoint: userspace endpoint creation with full capability grant
- DebugPutchar: debug output to UART from userspace
- MapPage: cross-process page mapping (init loads binaries into children)
- SpawnThreadIn: spawn thread in another process via capability
Key fixes:
- Per-process L1 page tables for VPN[2]=0 (prevents cross-process corruption)
- Separate kernel_pt from page_tables[0] (init pid=0 overwrote kernel PT ref)
- Thread Running state set in switch_to_next (syscalls rejected without it)
- Pending IPC results applied during context switch
- SIE disabled during boot (timer can't preempt into unready processes)
- User heap VA starts at 0x40000 (avoids shared buffer at 0x30000)
- RequestPages maps at user VAs via per-process heap allocator
VirtIO GPU:
- Adapter probes for GPU device, initializes resource/scanout/backing
- Display server writes to mapped framebuffer, flushes via GPU virtqueue
- 640x480 BGRA framebuffer with transfer-to-host and resource-flush
Storage server:
- Userspace VirtIO block driver using pre-mapped MMIO and DMA pages
- FAT16 filesystem reader serving file-read requests via IPC
- Shared buffer protocol: init writes filename, storage writes file data
Echo app for IPC testing (adapter-loaded echo proved the pipeline end-to-end).
- Halt syscall: only pid 0 (init) can halt, adapter uses SBI SRST
- Fault notification: kernel delivers fault info to process fault handler endpoint before killing
- Supervisor: tracks restart counts, back-off up to 5 restarts
- Shutdown: notifies servers, waits with timeout, calls halt
- Trap handler: faults now call kernel.handle_fault instead of halting
Add Priority::DEFAULT and TimeSlice::DEFAULT to types crate.
All QEMU virt addresses consolidated in board.rs.
Structure mirrors future adapter-arm/ layout.
