k i think this is enough to trace through a testcase w/o tracing thro…

…ugh interrupts
0vercl0k · May 12, 2024 · 3c57d0c · 3c57d0c
1 parent 06101a5
commit 3c57d0c
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Showing 2 changed files with 50 additions and 36 deletions.
diff --git a/src/wtf/ram.h b/src/wtf/ram.h
@@ -13,7 +13,7 @@ struct Page {
  // Page size.
  //
 
- static constexpr uint64_t Size = 0x1000;
+ static constexpr uint64_t Size = 0x1'000;
 };
 
 //

diff --git a/src/wtf/whv_backend.cc b/src/wtf/whv_backend.cc
@@ -7,7 +7,7 @@
 #include <algorithm>
 #include <fstream>
 
-constexpr bool WhvLoggingOn = true;
+constexpr bool WhvLoggingOn = false;
 
 template <typename... Args_t>
 void WhvDebugPrint(const char *Format, const Args_t &...args) {
@@ -1136,49 +1136,63 @@ WhvBackend_t::OnDebugTrap(const WHV_RUN_VP_EXIT_CONTEXT &Exception) {
  // to continue execution.
  //
 
- if (LastBreakpointGpa_ == Gpa_t(0xffffffffffffffff)) {
- if (TraceType_ == TraceType_t::Rip) {
+ bool StripTrapFlag = true;
 
- //
- // OK we got here because we are single stepping through the testcase.
- //
+ WhvDebugPrint("Received debug trap @ {:#x}\n", Exception.VpContext.Rip);
+
+ if (TraceType_ == TraceType_t::Rip) {
+
+ //
+ // OK we got here because we are single stepping through the testcase.
+ //
 
- WHV_X64_INTERRUPT_STATE_REGISTER InterruptState;
- InterruptState.AsUINT64 = GetReg64(WHvRegisterInterruptState);
- InterruptState.InterruptShadow = 0;
- if (FAILED(
- SetReg64(WHvRegisterInterruptState, InterruptState.AsUINT64))) {
- fmt::print("Failed to set WHvRegisterInterruptState\n");
- std::abort();
- }
-
- fmt::print(TraceFile_, "{:#x}\n", Exception.VpContext.Rip,
- GetReg64(WHvX64RegisterRflags));
- return SetReg64(WHvX64RegisterRflags,
- Exception.VpContext.Rflags | RFLAGS_TRAP_FLAG_FLAG);
+ WHV_X64_INTERRUPT_STATE_REGISTER InterruptState;
+ InterruptState.AsUINT64 = GetReg64(WHvRegisterInterruptState);
+ InterruptState.InterruptShadow = 0;
+ const HRESULT Hr =
+ SetReg64(WHvRegisterInterruptState, InterruptState.AsUINT64);
+ if (FAILED(Hr)) {
+ fmt::print("Failed to set WHvRegisterInterruptState\n");
+ return Hr;
  }
 
- fmt::print(
- "Got into OnDebugTrap with LastBreakpointGpa_ = 0xffffffffffffffff");
- std::abort();
- }
+ fmt::print(TraceFile_, "{:#x}\n", Exception.VpContext.Rip,
+ GetReg64(WHvX64RegisterRflags));
 
- //
- // Remember if we get there, it is because we hit a breakpoint, turned on
- // TF in order to step over the instruction, and now we get the chance to
- // turn it back on.
- //
+ StripTrapFlag = false;
+ } else {
+ if (LastBreakpointGpa_ == Gpa_t(0xffffffffffffffff)) {
+ fmt::print(
+ "Got into OnDebugTrap with LastBreakpointGpa_ = 0xffffffffffffffff");
+ std::abort();
+ }
 
- Ram_.AddBreakpoint(LastBreakpointGpa_);
+  WhvDebugPrint("Resetting breakpoint @ {:#x}", LastBreakpointGpa_);
 
- //
- // Strip TF off Rflags.
- //
+ //
+ // Remember if we get there, it is because we hit a breakpoint, turned on
+ // TF in order to step over the instruction, and now we get the chance to
+ // turn it back on.
+ //
+
+ Ram_.AddBreakpoint(LastBreakpointGpa_);
 
- WhvDebugPrint("Turning off RFLAGS.TF\n");
- LastBreakpointGpa_ = Gpa_t(0xffffffffffffffff);
+ //
+ // Either strip or turn on TF.
+ //
+
+ LastBreakpointGpa_ = Gpa_t(0xffffffffffffffff);
+ }
+
+ if (StripTrapFlag) {
+ WhvDebugPrint("Turning off RFLAGS.TF\n");
+ return SetReg64(WHvX64RegisterRflags,
+ Exception.VpContext.Rflags & (~RFLAGS_TRAP_FLAG_FLAG));
+ }
+
+ WhvDebugPrint("Setting RFLAGS.TF\n");
  return SetReg64(WHvX64RegisterRflags,
- Exception.VpContext.Rflags & (~RFLAGS_TRAP_FLAG_FLAG));
+ Exception.VpContext.Rflags | RFLAGS_TRAP_FLAG_FLAG);
 }
 
 HRESULT