https://git.reactos.org/?p=reactos.git;a=commitdiff;h=70bf3bb8fa7ed1eefde808efb3b43e85040b24bf
commit 70bf3bb8fa7ed1eefde808efb3b43e85040b24bf
Author: Hervé Poussineau <hpous...@reactos.org>
AuthorDate: Sat Oct 12 07:46:41 2024 +0200
Commit: Hervé Poussineau <hpous...@reactos.org>
CommitDate: Wed Jan 29 18:25:24 2025 +0100
[NTOS:KDBG] Add back 'cregs' command
This command was removed in commit baa47fa5e06948b7e76ba820f7a342547eaf0cde
because there was no way to get the CRx registers from a CONTEXT structure.
Previous code was also displaying current GDTR/LDTR and IDT.
Rewrite the code to use KdSystemDebugControl(SysDbgReadControlSpace, ...)
to get CRx, GDTR/LDTR and IDT values just before entering debugger.
---
ntoskrnl/kdbg/kdb_cli.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 79 insertions(+)
diff --git a/ntoskrnl/kdbg/kdb_cli.c b/ntoskrnl/kdbg/kdb_cli.c
index b4794dca739..c86b770c81d 100644
--- a/ntoskrnl/kdbg/kdb_cli.c
+++ b/ntoskrnl/kdbg/kdb_cli.c
@@ -353,6 +353,7 @@ static const struct
#endif // _M_IX86
{ "x", "x [address] [L count]", "Display count dwords, starting at
address.", KdbpCmdDisassembleX },
{ "regs", "regs", "Display general purpose registers.", KdbpCmdRegs },
+ { "cregs", "cregs", "Display control, descriptor table and task segment
registers.", KdbpCmdRegs },
{ "sregs", "sregs", "Display status registers.", KdbpCmdRegs },
{ "dregs", "dregs", "Display debug registers.", KdbpCmdRegs },
{ "bt", "bt [*frameaddr|thread id]", "Prints current backtrace or from
given frame address.", KdbpCmdBackTrace },
@@ -984,6 +985,84 @@ KdbpCmdRegs(
}
KdbpPrint("\n");
}
+ else if (Argv[0][0] == 'c') /* cregs */
+ {
+ ULONG Cr0, Cr2, Cr3, Cr4;
+ KDESCRIPTOR Gdtr = {0, 0, 0}, Idtr = {0, 0, 0};
+ USHORT Ldtr, Tr;
+ static const PCHAR Cr0Bits[32] = { " PE", " MP", " EM", " TS", " ET",
" NE", NULL, NULL,
+ NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL,
+ " WP", NULL, " AM", NULL, NULL,
NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL, NULL, "
NW", " CD", " PG" };
+ static const PCHAR Cr4Bits[32] = { " VME", " PVI", " TSD", " DE", "
PSE", " PAE", " MCE", " PGE",
+ " PCE", " OSFXSR", " OSXMMEXCPT",
NULL, NULL, NULL, NULL, NULL,
+ NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL,
+ NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL };
+ SYSDBG_CONTROL_SPACE Input;
+ KSPECIAL_REGISTERS SpecialRegisters;
+ NTSTATUS Status = STATUS_NOT_IMPLEMENTED;
+
+ /* Retrieve the control registers */
+ RtlZeroMemory(&Input, sizeof(Input));
+ Input.Buffer = &SpecialRegisters;
+ Input.Request = sizeof(SpecialRegisters);
+#ifdef _M_IX86
+ Input.Address = sizeof(CONTEXT);
+#else
+ Input.Address = AMD64_DEBUG_CONTROL_SPACE_KSPECIAL;
+#endif
+ Status = KdSystemDebugControl(SysDbgReadControlSpace,
+ &Input, sizeof(Input),
+ NULL, 0,
+ NULL, KernelMode);
+ if (!NT_SUCCESS(Status))
+ {
+ KdbpPrint("Failed to get registers: status 0x%08x\n", Status);
+ return TRUE;
+ }
+ Cr0 = SpecialRegisters.Cr0;
+ Cr2 = SpecialRegisters.Cr2;
+ Cr3 = SpecialRegisters.Cr3;
+ Cr4 = SpecialRegisters.Cr4;
+
+ /* Retrieve the descriptor table and task segment registers */
+ Gdtr = SpecialRegisters.Gdtr;
+ Ldtr = SpecialRegisters.Ldtr;
+ Idtr = SpecialRegisters.Idtr;
+ Tr = SpecialRegisters.Tr;
+
+ /* Display the control registers */
+ KdbpPrint("CR0 0x%08x ", Cr0);
+ for (i = 0; i < 32; i++)
+ {
+ if (!Cr0Bits[i])
+ continue;
+
+ if ((Cr0 & (1 << i)) != 0)
+ KdbpPrint(Cr0Bits[i]);
+ }
+ KdbpPrint("\n");
+
+ KdbpPrint("CR2 0x%08x\n", Cr2);
+ KdbpPrint("CR3 0x%08x Pagedir-Base 0x%08x %s%s\n", Cr3, (Cr3 &
0xfffff000),
+ (Cr3 & (1 << 3)) ? " PWT" : "", (Cr3 & (1 << 4)) ? " PCD" :
"" );
+ KdbpPrint("CR4 0x%08x ", Cr4);
+ for (i = 0; i < 32; i++)
+ {
+ if (!Cr4Bits[i])
+ continue;
+
+ if ((Cr4 & (1 << i)) != 0)
+ KdbpPrint(Cr4Bits[i]);
+ }
+ KdbpPrint("\n");
+
+ /* Display the descriptor table and task segment registers */
+ KdbpPrint("GDTR Base 0x%08x Size 0x%04x\n", Gdtr.Base, Gdtr.Limit);
+ KdbpPrint("LDTR 0x%04x\n", Ldtr);
+ KdbpPrint("IDTR Base 0x%08x Size 0x%04x\n", Idtr.Base, Idtr.Limit);
+ KdbpPrint("TR 0x%04x\n", Tr);
+ }
else if (Argv[0][0] == 's') /* sregs */
{
KdbpPrint("CS 0x%04x Index 0x%04x %cDT RPL%d\n",
