core/debugger: memory breakpoint support

This commit is contained in:
Liam 2022-06-06 12:56:01 -04:00
parent f86b770ff7
commit 208ed712f4
19 changed files with 520 additions and 64 deletions

View file

@ -44,12 +44,14 @@ static std::span<const u8> ReceiveInto(Readable& r, Buffer& buffer) {
enum class SignalType {
Stopped,
Watchpoint,
ShuttingDown,
};
struct SignalInfo {
SignalType type;
Kernel::KThread* thread;
const Kernel::DebugWatchpoint* watchpoint;
};
namespace Core {
@ -157,13 +159,19 @@ private:
void PipeData(std::span<const u8> data) {
switch (info.type) {
case SignalType::Stopped:
case SignalType::Watchpoint:
// Stop emulation.
PauseEmulation();
// Notify the client.
active_thread = info.thread;
UpdateActiveThread();
frontend->Stopped(active_thread);
if (info.type == SignalType::Watchpoint) {
frontend->Watchpoint(active_thread, *info.watchpoint);
} else {
frontend->Stopped(active_thread);
}
break;
case SignalType::ShuttingDown:
@ -290,12 +298,17 @@ Debugger::Debugger(Core::System& system, u16 port) {
Debugger::~Debugger() = default;
bool Debugger::NotifyThreadStopped(Kernel::KThread* thread) {
return impl && impl->SignalDebugger(SignalInfo{SignalType::Stopped, thread});
return impl && impl->SignalDebugger(SignalInfo{SignalType::Stopped, thread, nullptr});
}
bool Debugger::NotifyThreadWatchpoint(Kernel::KThread* thread,
const Kernel::DebugWatchpoint& watch) {
return impl && impl->SignalDebugger(SignalInfo{SignalType::Watchpoint, thread, &watch});
}
void Debugger::NotifyShutdown() {
if (impl) {
impl->SignalDebugger(SignalInfo{SignalType::ShuttingDown, nullptr});
impl->SignalDebugger(SignalInfo{SignalType::ShuttingDown, nullptr, nullptr});
}
}

View file

@ -9,7 +9,8 @@
namespace Kernel {
class KThread;
}
struct DebugWatchpoint;
} // namespace Kernel
namespace Core {
class System;
@ -40,6 +41,11 @@ public:
*/
void NotifyShutdown();
/*
* Notify the debugger that the given thread has stopped due to hitting a watchpoint.
*/
bool NotifyThreadWatchpoint(Kernel::KThread* thread, const Kernel::DebugWatchpoint& watch);
private:
std::unique_ptr<DebuggerImpl> impl;
};

View file

@ -11,7 +11,8 @@
namespace Kernel {
class KThread;
}
struct DebugWatchpoint;
} // namespace Kernel
namespace Core {
@ -71,6 +72,11 @@ public:
*/
virtual void ShuttingDown() = 0;
/*
* Called when emulation has stopped on a watchpoint.
*/
virtual void Watchpoint(Kernel::KThread* thread, const Kernel::DebugWatchpoint& watch) = 0;
/**
* Called when new data is asynchronously received on the client socket.
* A list of actions to perform is returned.

View file

@ -112,6 +112,23 @@ void GDBStub::Stopped(Kernel::KThread* thread) {
SendReply(arch->ThreadStatus(thread, GDB_STUB_SIGTRAP));
}
void GDBStub::Watchpoint(Kernel::KThread* thread, const Kernel::DebugWatchpoint& watch) {
const auto status{arch->ThreadStatus(thread, GDB_STUB_SIGTRAP)};
switch (watch.type) {
case Kernel::DebugWatchpointType::Read:
SendReply(fmt::format("{}rwatch:{:x};", status, watch.start_address));
break;
case Kernel::DebugWatchpointType::Write:
SendReply(fmt::format("{}watch:{:x};", status, watch.start_address));
break;
case Kernel::DebugWatchpointType::ReadOrWrite:
default:
SendReply(fmt::format("{}awatch:{:x};", status, watch.start_address));
break;
}
}
std::vector<DebuggerAction> GDBStub::ClientData(std::span<const u8> data) {
std::vector<DebuggerAction> actions;
current_command.insert(current_command.end(), data.begin(), data.end());
@ -278,44 +295,124 @@ void GDBStub::ExecuteCommand(std::string_view packet, std::vector<DebuggerAction
case 'c':
actions.push_back(DebuggerAction::Continue);
break;
case 'Z': {
const auto addr_sep{std::find(command.begin(), command.end(), ',') - command.begin() + 1};
const size_t addr{static_cast<size_t>(strtoll(command.data() + addr_sep, nullptr, 16))};
if (system.Memory().IsValidVirtualAddress(addr)) {
replaced_instructions[addr] = system.Memory().Read32(addr);
system.Memory().Write32(addr, arch->BreakpointInstruction());
system.InvalidateCpuInstructionCacheRange(addr, sizeof(u32));
SendReply(GDB_STUB_REPLY_OK);
} else {
SendReply(GDB_STUB_REPLY_ERR);
}
case 'Z':
HandleBreakpointInsert(command);
break;
}
case 'z': {
const auto addr_sep{std::find(command.begin(), command.end(), ',') - command.begin() + 1};
const size_t addr{static_cast<size_t>(strtoll(command.data() + addr_sep, nullptr, 16))};
const auto orig_insn{replaced_instructions.find(addr)};
if (system.Memory().IsValidVirtualAddress(addr) &&
orig_insn != replaced_instructions.end()) {
system.Memory().Write32(addr, orig_insn->second);
system.InvalidateCpuInstructionCacheRange(addr, sizeof(u32));
replaced_instructions.erase(addr);
SendReply(GDB_STUB_REPLY_OK);
} else {
SendReply(GDB_STUB_REPLY_ERR);
}
case 'z':
HandleBreakpointRemove(command);
break;
}
default:
SendReply(GDB_STUB_REPLY_EMPTY);
break;
}
}
enum class BreakpointType {
Software = 0,
Hardware = 1,
WriteWatch = 2,
ReadWatch = 3,
AccessWatch = 4,
};
void GDBStub::HandleBreakpointInsert(std::string_view command) {
const auto type{static_cast<BreakpointType>(strtoll(command.data(), nullptr, 16))};
const auto addr_sep{std::find(command.begin(), command.end(), ',') - command.begin() + 1};
const auto size_sep{std::find(command.begin() + addr_sep, command.end(), ',') -
command.begin() + 1};
const size_t addr{static_cast<size_t>(strtoll(command.data() + addr_sep, nullptr, 16))};
const size_t size{static_cast<size_t>(strtoll(command.data() + size_sep, nullptr, 16))};
if (!system.Memory().IsValidVirtualAddressRange(addr, size)) {
SendReply(GDB_STUB_REPLY_ERR);
return;
}
bool success{};
switch (type) {
case BreakpointType::Software:
replaced_instructions[addr] = system.Memory().Read32(addr);
system.Memory().Write32(addr, arch->BreakpointInstruction());
system.InvalidateCpuInstructionCacheRange(addr, sizeof(u32));
success = true;
break;
case BreakpointType::WriteWatch:
success = system.CurrentProcess()->InsertWatchpoint(system, addr, size,
Kernel::DebugWatchpointType::Write);
break;
case BreakpointType::ReadWatch:
success = system.CurrentProcess()->InsertWatchpoint(system, addr, size,
Kernel::DebugWatchpointType::Read);
break;
case BreakpointType::AccessWatch:
success = system.CurrentProcess()->InsertWatchpoint(
system, addr, size, Kernel::DebugWatchpointType::ReadOrWrite);
break;
case BreakpointType::Hardware:
default:
SendReply(GDB_STUB_REPLY_EMPTY);
return;
}
if (success) {
SendReply(GDB_STUB_REPLY_OK);
} else {
SendReply(GDB_STUB_REPLY_ERR);
}
}
void GDBStub::HandleBreakpointRemove(std::string_view command) {
const auto type{static_cast<BreakpointType>(strtoll(command.data(), nullptr, 16))};
const auto addr_sep{std::find(command.begin(), command.end(), ',') - command.begin() + 1};
const auto size_sep{std::find(command.begin() + addr_sep, command.end(), ',') -
command.begin() + 1};
const size_t addr{static_cast<size_t>(strtoll(command.data() + addr_sep, nullptr, 16))};
const size_t size{static_cast<size_t>(strtoll(command.data() + size_sep, nullptr, 16))};
if (!system.Memory().IsValidVirtualAddressRange(addr, size)) {
SendReply(GDB_STUB_REPLY_ERR);
return;
}
bool success{};
switch (type) {
case BreakpointType::Software: {
const auto orig_insn{replaced_instructions.find(addr)};
if (orig_insn != replaced_instructions.end()) {
system.Memory().Write32(addr, orig_insn->second);
system.InvalidateCpuInstructionCacheRange(addr, sizeof(u32));
replaced_instructions.erase(addr);
success = true;
}
break;
}
case BreakpointType::WriteWatch:
success = system.CurrentProcess()->RemoveWatchpoint(system, addr, size,
Kernel::DebugWatchpointType::Write);
break;
case BreakpointType::ReadWatch:
success = system.CurrentProcess()->RemoveWatchpoint(system, addr, size,
Kernel::DebugWatchpointType::Read);
break;
case BreakpointType::AccessWatch:
success = system.CurrentProcess()->RemoveWatchpoint(
system, addr, size, Kernel::DebugWatchpointType::ReadOrWrite);
break;
case BreakpointType::Hardware:
default:
SendReply(GDB_STUB_REPLY_EMPTY);
return;
}
if (success) {
SendReply(GDB_STUB_REPLY_OK);
} else {
SendReply(GDB_STUB_REPLY_ERR);
}
}
// Structure offsets are from Atmosphere
// See osdbg_thread_local_region.os.horizon.hpp and osdbg_thread_type.os.horizon.hpp

View file

@ -24,6 +24,7 @@ public:
void Connected() override;
void Stopped(Kernel::KThread* thread) override;
void ShuttingDown() override;
void Watchpoint(Kernel::KThread* thread, const Kernel::DebugWatchpoint& watch) override;
std::vector<DebuggerAction> ClientData(std::span<const u8> data) override;
private:
@ -31,6 +32,8 @@ private:
void ExecuteCommand(std::string_view packet, std::vector<DebuggerAction>& actions);
void HandleVCont(std::string_view command, std::vector<DebuggerAction>& actions);
void HandleQuery(std::string_view command);
void HandleBreakpointInsert(std::string_view command);
void HandleBreakpointRemove(std::string_view command);
std::vector<char>::const_iterator CommandEnd() const;
std::optional<std::string> DetachCommand();
Kernel::KThread* GetThreadByID(u64 thread_id);