Split KdSendPacket and KdReceivePacket into those that manipulate the
KDBG state proper (reside in kdbg/kdbg.c), and those that deal only with
debug input/output that will reside in a KDTERM "KD Terminal Driver" DLL.
Based on some previous preparatory work by Hervé Poussineau in PR #4600.
(Equivalents of commits 5162bf106 and partly e9bcf7275.)
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.
- 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".
Our legacy KD module is slowly being phased out for the more recent KD64
Kernel Debugger that supports WinDbg, but at the same time we must retain
support for GCC debugging and the KDBG interface.
For the time being few #ifdef _WINKD_ have been introduced in KD64 so that
some of its code/data does not completely get shared yet with the legacy KD,
until the latter becomes phased out.
KD Modifications:
=================
- Remove the implementation of NtQueryDebugFilterState() /
NtSetDebugFilterState() that now comes entirely from KD64.
- Remove KD variables that are now shared with KD64.
- Share common code with KD64: KdpMoveMemory(), KdpZeroMemory(),
KdpCopyMemoryChunks(), KdpPrint(), KdpPrompt().
- KDBG: Remove the duplicated KdpCopyMemoryChunks() function.
- In KdpServiceDispatcher() and KdpEnterDebuggerException(), call the
KdpPrint() worker function that correctly probes and captures its arguments.
- Temporarily stub out KdEnterDebugger() and KdExitDebugger() that is used
by the shared code, until KD is removed and only the KD64 version of these
functions remain.
- Re-implement the KD/KDBG KdpPrompt() function using a custom KdpPromptString()
helper compatible with KD64, that is called by the KD64 implementation of
KdpPrompt(). This KdpPromptString() helper now issues the prompt on all
the KD loggers: e.g. if you use both at the same time COM-port and SCREEN
debugging, the prompt will appear on both. Before that the prompt was always
being displayed on COM port even if e.g. a SCREEN-only debug session was used...
- ppc_irq.c: Fix the prototype of KdpServiceDispatcher().
KD64 Fixes:
===========
- Initialize the MaximumLength member of the counted STRING variables
before using them elsewhere.
- Get rid of alloca() within SEH block in KdpPrint() (addendum to 7b95fcf9).
- Add the ROS-specific handy dump commands in KdSystemDebugControl().
- Introduce KdpScreenAcquire() / KdpScreenRelease() helpers that allow
to correctly acquire or release the screen when using INBV for
"Screen-Mode" debugging.
- Introduce KdpAcquireLock() / KdpReleaseLock() helpers so as to reduce
the copy-pasted code required when acquiring spin-locks in the KD debug
logger functions.
- Close the opened KdpLogFileHandle file in the KdpInitDebugLog() logger
in case we failed to create the logger writer thread.
Also use explicit kernel-mode handle when opening the log file.
- static-ify some local variables, remove few hardcoded values, and
minor formatting.
- Correctly define the INIT_FUNCTION's.
- Always include kd64.h
- Change KdpPrompt() prototype to be compatible between KDBG and _WINDK_
- Rename KdComponentTable to KdpComponentTable to prevent a conflict
- Add some functions stubs and global variables
