CORE-17470
+ KdpDebugLogInit: Add resources cleanup in failure code paths.
Fix, in an NT-compatible manner, how (and when) the KD/KDBG BootPhase >=2
initialization steps are performed.
These are necessary for any functionality KDBG needs, that would depend
on the NT I/O Manager and the storage and filesystem stacks to be running.
This includes, creating the debug log file, and for KDBG, loading its
KDBinit initialization file.
As a result, file debug logging is fixed.
The old ReactOS-specific (NT-incompatible) callback we did in the middle
of IoInitSystem() is removed, in favor of a runtime mechanism that should
work on Windows as well.
The idea for this new mechanism is loosely inspired by the TDL4 rootkit,
see http://blog.w4kfu.com/public/tdl4_article/draft_tdl4article.html
but contrary to it, a specific hook is used instead, as well as the
technique of driver reinitialization:
https://web.archive.org/web/20211021050515/https://driverentry.com.br/en/blog/?p=261
Its rationale is as follows:
We want to be able to perform I/O-related initialization (starting a
logger thread for file log debugging, loading KDBinit file for KDBG,
etc.). A good place for this would be as early as possible, once the
I/O Manager has started the storage and the boot filesystem drivers.
Here is an overview of the initialization steps of the NT Kernel and
Executive:
----
KiSystemStartup(KeLoaderBlock)
if (Cpu == 0) KdInitSystem(0, KeLoaderBlock);
KiSwitchToBootStack() -> KiSystemStartupBootStack()
-> KiInitializeKernel() -> ExpInitializeExecutive(Cpu, KeLoaderBlock)
(NOTE: Any unexpected debugger break will call KdInitSystem(0, NULL); )
KdInitSystem(0, LoaderBlock) -> KdDebuggerInitialize0(LoaderBlock);
ExpInitializeExecutive(Cpu == 0): ExpInitializationPhase = 0;
HalInitSystem(0, KeLoaderBlock); <-- Sets HalInitPnpDriver callback.
...
PsInitSystem(LoaderBlock)
PsCreateSystemThread(Phase1Initialization)
Phase1Initialization(Discard): ExpInitializationPhase = 1;
HalInitSystem(1, KeLoaderBlock);
...
Early initialization of Ob, Ex, Ke.
KdInitSystem(1, KeLoaderBlock);
...
KdDebuggerInitialize1(LoaderBlock);
...
IoInitSystem(LoaderBlock);
...
----
As we can see, KdDebuggerInitialize1() is the last KD initialization
routine the kernel calls, and is called *before* the I/O Manager starts.
Thus, direct Nt/ZwCreateFile ... calls done there would fail. Also,
we want to do the I/O initialization as soon as possible. There does
not seem to be any exported way to be notified about the I/O manager
initialization steps... that is, unless we somehow become a driver and
insert ourselves in the flow!
Since we are not a regular driver, we need to invoke IoCreateDriver()
to create one. However, remember that we are currently running *before*
IoInitSystem(), the I/O subsystem is not initialized yet. Due to this,
calling IoCreateDriver(), much like any other IO functions, would lead
to a crash, because it calls
ObCreateObject(..., IoDriverObjectType, ...), and IoDriverObjectType
is non-initialized yet (it's NULL).
The chosen solution is to hook a "known" exported callback: namely, the
HalInitPnpDriver() callback (it initializes the "HAL Root Bus Driver").
It is set very early on by the HAL via the HalInitSystem(0, ...) call,
and is called early on by IoInitSystem() before any driver is loaded,
but after the I/O Manager has been minimally set up so that new drivers
can be created.
When the hook: KdpInitDriver() is called, we create our driver with
IoCreateDriver(), specifying its entrypoint KdpDriverEntry(), then
restore and call the original HalInitPnpDriver() callback.
Another possible unexplored alternative, could be to insert ourselves
in the KeLoaderBlock->LoadOrderListHead boot modules list, or in the
KeLoaderBlock->BootDriverListHead boot-driver list. (Note that while
we may be able to do this, because boot-drivers are resident in memory,
much like we are, we cannot insert ourselves in the system-driver list
however, since those drivers are expected to come from PE image files.)
Once the KdpDriverEntry() driver entrypoint is called, we register
KdpDriverReinit() for re-initialization with the I/O Manager, in order
to provide more initialization points. KdpDriverReinit() calls the KD
providers at BootPhase >= 2, and schedules further reinitializations
(at most 3 more) if any of the providers request so.
CORE-10749
The dmesg command is now available even if screen output is disabled.
Co-authored-by: Hermès Bélusca-Maïto <hermes.belusca-maito@reactos.org>
- KdbSymInit() in kdb_symbols.c only initializes symbols implementation
support.
- The rest of KdbInitialize gets moved into kdb_cli.c and initializes
the KDBG debugger itself.
- Move KdbDebugPrint to kdb_cli.c as well.
- Use SAL2 annotations.
- KdSendPacket(): Validate DEBUG_IO API call.
- KdReceivePacket(): Take the LengthOfStringRead into account; use
KdbpReadCommand() to read the input, so that correct line edition
is available (backspace, etc.)
If you ask why there are two sets of functions that do the same, it's
because this file (and the kdmain.c) will very soon some day be moved to
a transport dll, outside the kernel, and it will need these functions.
- Remove KdbInit() macro and directly use KdbpCliInit() (since the place
where it was used was already within an #ifdef KDBG block).
- Declare KdpKdbgInit() only when KDBG is defined, move its definition
into kdio.c and remove the legacy wrappers/kdbg.c file.
And in KdbInitialize(), set KdpInitRoutine directly to the former,
instead of using the KdpKdbgInit indirection.
- Don't reset KdComPortInUse in KdpDebugLogInit().
- Minor refactorings: KdpSerialDebugPrint -> KdpSerialPrint and make it
static; argument name "Message" -> "String", "StringLength" -> "Length".
KD64: Raise to HIGH_LEVEL when entering trap
KDBG: lower to DISPATCH_LEVEL when applying IRQL hack & use a worker thread to load symbols
KD&KDBG: Actually unload symbols when required
Phase 2 and 3 were not done anymore since 777a2d94da.
Fix that, by merging phases 1 and 2, and by calling phase 3 later
for log file debugging, when ExpInitializationPhase = 3
CORE-17470
- Change INIT_FUNCTION and INIT_SECTION to CODE_SEG("INIT") and DATA_SEG("INIT") respectively
- Remove INIT_FUNCTION from function prototypes
- Remove alloc_text pragma calls as they are not needed anymore
- Add boot video color constants
- Refactor palette initialization
- Move some common stuff in right place
- Get rid of some magic constants and hardcoded values
- Get rid of TopDelta variable (calculated at compile time)
- Update SAL annotations
Addendum to 5f2ca473. CORE-16216 CORE-16219
According to PC-9801 Bible p. 50, divisor for PIT will become unsupported in some cases after having removed the fractional part. Replace 19200 value with 9600 which is supported by both 10 MHz and 8 MHz machines.
