Jason Molenda c73a3f16f8 [lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)
This patch is rearranging code a bit to add WatchpointResources to
Process. A WatchpointResource is meant to represent a hardware
watchpoint register in the inferior process. It has an address, a size,
a type, and a list of Watchpoints that are using this
WatchpointResource.

This current patch doesn't add any of the features of
WatchpointResources that make them interesting -- a user asking to watch
a 24 byte object could watch this with three 8 byte WatchpointResources.
Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at
0x1003, these must both be served by a single WatchpointResource on that
doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint
registers were used to track these separately, one of them may not be
hit. Or if you have one Watchpoint on a variable with a condition set,
and another Watchpoint on that same variable with a command defined or
different condition, or ignorecount, both of those Watchpoints need to
evaluate their criteria/commands when their WatchpointResource has been
hit.

There's a bit of code movement to rearrange things in the direction I'll
need for implementing this feature, so I want to start with reviewing &
landing this mostly NFC patch and we can focus on the algorithmic
choices about how WatchpointResources are shared and handled as they're
triggeed, separately.

This patch also stops printing "Watchpoint <n> hit: old value: <x>, new
vlaue: <y>" for Read watchpoints. I could make an argument for print
"Watchpoint <n> hit: current value <x>" but the current output doesn't
make any sense, and the user can print the value if they are
particularly interested. Read watchpoints are used primarily to
understand what code is reading a variable.

This patch adds more fallbacks for how to print the objects being
watched if we have types, instead of assuming they are all integral
values, so a struct will print its elements. As large watchpoints are
added, we'll be doing a lot more of those.

To track the WatchpointSP in the WatchpointResources, I changed the
internal API which took a WatchpointSP and devolved it to a Watchpoint*,
which meant touching several different Process files. I removed the
watchpoint code in ProcessKDP which only reported that watchpoints
aren't supported, the base class does that already.

I haven't yet changed how we receive a watchpoint to identify the
WatchpointResource responsible for the trigger, and identify all
Watchpoints that are using this Resource to evaluate their conditions
etc. This is the same work that a BreakpointSite needs to do when it has
been tiggered, where multiple Breakpoints may be at the same address.

There is not yet any printing of the Resources that a Watchpoint is
implemented in terms of ("watchpoint list", or
SBWatchpoint::GetDescription).

"watchpoint set var" and "watchpoint set expression" take a size
argument which was previously 1, 2, 4, or 8 (an enum). I've changed this
to an unsigned int. Most hardware implementations can only watch 1, 2,
4, 8 byte ranges, but with Resources we'll allow a user to ask for
different sized watchpoints and set them in hardware-expressble terms
soon.

I've annotated areas where I know there is work still needed with
LWP_TODO that I'll be working on once this is landed.

I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS.

https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
(cherry picked from commit fc6b72523f3d73b921690a713e97a433c96066c6)
2023-11-30 14:59:10 -08:00

984 lines
34 KiB
C++

//===-- ProcessKDP.cpp ----------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include <cerrno>
#include <cstdlib>
#include <memory>
#include <mutex>
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Host/ConnectionFileDescriptor.h"
#include "lldb/Host/Host.h"
#include "lldb/Host/ThreadLauncher.h"
#include "lldb/Host/common/TCPSocket.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandObject.h"
#include "lldb/Interpreter/CommandObjectMultiword.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/OptionGroupString.h"
#include "lldb/Interpreter/OptionGroupUInt64.h"
#include "lldb/Interpreter/OptionValueProperties.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/State.h"
#include "lldb/Utility/StringExtractor.h"
#include "lldb/Utility/UUID.h"
#include "llvm/Support/Threading.h"
#define USEC_PER_SEC 1000000
#include "Plugins/DynamicLoader/Darwin-Kernel/DynamicLoaderDarwinKernel.h"
#include "Plugins/DynamicLoader/Static/DynamicLoaderStatic.h"
#include "ProcessKDP.h"
#include "ProcessKDPLog.h"
#include "ThreadKDP.h"
using namespace lldb;
using namespace lldb_private;
LLDB_PLUGIN_DEFINE_ADV(ProcessKDP, ProcessMacOSXKernel)
namespace {
#define LLDB_PROPERTIES_processkdp
#include "ProcessKDPProperties.inc"
enum {
#define LLDB_PROPERTIES_processkdp
#include "ProcessKDPPropertiesEnum.inc"
};
class PluginProperties : public Properties {
public:
static llvm::StringRef GetSettingName() {
return ProcessKDP::GetPluginNameStatic();
}
PluginProperties() : Properties() {
m_collection_sp = std::make_shared<OptionValueProperties>(GetSettingName());
m_collection_sp->Initialize(g_processkdp_properties);
}
~PluginProperties() override = default;
uint64_t GetPacketTimeout() {
const uint32_t idx = ePropertyKDPPacketTimeout;
return GetPropertyAtIndexAs<uint64_t>(
idx, g_processkdp_properties[idx].default_uint_value);
}
};
} // namespace
static PluginProperties &GetGlobalPluginProperties() {
static PluginProperties g_settings;
return g_settings;
}
static const lldb::tid_t g_kernel_tid = 1;
llvm::StringRef ProcessKDP::GetPluginDescriptionStatic() {
return "KDP Remote protocol based debugging plug-in for darwin kernel "
"debugging.";
}
void ProcessKDP::Terminate() {
PluginManager::UnregisterPlugin(ProcessKDP::CreateInstance);
}
lldb::ProcessSP ProcessKDP::CreateInstance(TargetSP target_sp,
ListenerSP listener_sp,
const FileSpec *crash_file_path,
bool can_connect) {
lldb::ProcessSP process_sp;
if (crash_file_path == NULL)
process_sp = std::make_shared<ProcessKDP>(target_sp, listener_sp);
return process_sp;
}
bool ProcessKDP::CanDebug(TargetSP target_sp, bool plugin_specified_by_name) {
if (plugin_specified_by_name)
return true;
// For now we are just making sure the file exists for a given module
Module *exe_module = target_sp->GetExecutableModulePointer();
if (exe_module) {
const llvm::Triple &triple_ref = target_sp->GetArchitecture().GetTriple();
switch (triple_ref.getOS()) {
case llvm::Triple::Darwin: // Should use "macosx" for desktop and "ios" for
// iOS, but accept darwin just in case
case llvm::Triple::MacOSX: // For desktop targets
case llvm::Triple::IOS: // For arm targets
case llvm::Triple::TvOS:
case llvm::Triple::WatchOS:
if (triple_ref.getVendor() == llvm::Triple::Apple) {
ObjectFile *exe_objfile = exe_module->GetObjectFile();
if (exe_objfile->GetType() == ObjectFile::eTypeExecutable &&
exe_objfile->GetStrata() == ObjectFile::eStrataKernel)
return true;
}
break;
default:
break;
}
}
return false;
}
// ProcessKDP constructor
ProcessKDP::ProcessKDP(TargetSP target_sp, ListenerSP listener_sp)
: Process(target_sp, listener_sp),
m_comm("lldb.process.kdp-remote.communication"),
m_async_broadcaster(NULL, "lldb.process.kdp-remote.async-broadcaster"),
m_kernel_load_addr(LLDB_INVALID_ADDRESS), m_command_sp(),
m_kernel_thread_wp() {
m_async_broadcaster.SetEventName(eBroadcastBitAsyncThreadShouldExit,
"async thread should exit");
m_async_broadcaster.SetEventName(eBroadcastBitAsyncContinue,
"async thread continue");
const uint64_t timeout_seconds =
GetGlobalPluginProperties().GetPacketTimeout();
if (timeout_seconds > 0)
m_comm.SetPacketTimeout(std::chrono::seconds(timeout_seconds));
}
// Destructor
ProcessKDP::~ProcessKDP() {
Clear();
// We need to call finalize on the process before destroying ourselves to
// make sure all of the broadcaster cleanup goes as planned. If we destruct
// this class, then Process::~Process() might have problems trying to fully
// destroy the broadcaster.
Finalize();
}
Status ProcessKDP::DoWillLaunch(Module *module) {
Status error;
error.SetErrorString("launching not supported in kdp-remote plug-in");
return error;
}
Status ProcessKDP::DoWillAttachToProcessWithID(lldb::pid_t pid) {
Status error;
error.SetErrorString(
"attaching to a by process ID not supported in kdp-remote plug-in");
return error;
}
Status ProcessKDP::DoWillAttachToProcessWithName(const char *process_name,
bool wait_for_launch) {
Status error;
error.SetErrorString(
"attaching to a by process name not supported in kdp-remote plug-in");
return error;
}
bool ProcessKDP::GetHostArchitecture(ArchSpec &arch) {
uint32_t cpu = m_comm.GetCPUType();
if (cpu) {
uint32_t sub = m_comm.GetCPUSubtype();
arch.SetArchitecture(eArchTypeMachO, cpu, sub);
// Leave architecture vendor as unspecified unknown
arch.GetTriple().setVendor(llvm::Triple::UnknownVendor);
arch.GetTriple().setVendorName(llvm::StringRef());
return true;
}
arch.Clear();
return false;
}
Status ProcessKDP::DoConnectRemote(llvm::StringRef remote_url) {
Status error;
// Don't let any JIT happen when doing KDP as we can't allocate memory and we
// don't want to be mucking with threads that might already be handling
// exceptions
SetCanJIT(false);
if (remote_url.empty()) {
error.SetErrorStringWithFormat("empty connection URL");
return error;
}
std::unique_ptr<ConnectionFileDescriptor> conn_up(
new ConnectionFileDescriptor());
if (conn_up) {
// Only try once for now.
// TODO: check if we should be retrying?
const uint32_t max_retry_count = 1;
for (uint32_t retry_count = 0; retry_count < max_retry_count;
++retry_count) {
if (conn_up->Connect(remote_url, &error) == eConnectionStatusSuccess)
break;
usleep(100000);
}
}
if (conn_up->IsConnected()) {
const TCPSocket &socket =
static_cast<const TCPSocket &>(*conn_up->GetReadObject());
const uint16_t reply_port = socket.GetLocalPortNumber();
if (reply_port != 0) {
m_comm.SetConnection(std::move(conn_up));
if (m_comm.SendRequestReattach(reply_port)) {
if (m_comm.SendRequestConnect(reply_port, reply_port,
"Greetings from LLDB...")) {
m_comm.GetVersion();
Target &target = GetTarget();
ArchSpec kernel_arch;
// The host architecture
GetHostArchitecture(kernel_arch);
ArchSpec target_arch = target.GetArchitecture();
// Merge in any unspecified stuff into the target architecture in
// case the target arch isn't set at all or incompletely.
target_arch.MergeFrom(kernel_arch);
target.SetArchitecture(target_arch);
/* Get the kernel's UUID and load address via KDP_KERNELVERSION
* packet. */
/* An EFI kdp session has neither UUID nor load address. */
UUID kernel_uuid = m_comm.GetUUID();
addr_t kernel_load_addr = m_comm.GetLoadAddress();
if (m_comm.RemoteIsEFI()) {
// Select an invalid plugin name for the dynamic loader so one
// doesn't get used since EFI does its own manual loading via
// python scripting
m_dyld_plugin_name = "none";
if (kernel_uuid.IsValid()) {
// If EFI passed in a UUID= try to lookup UUID The slide will not
// be provided. But the UUID lookup will be used to launch EFI
// debug scripts from the dSYM, that can load all of the symbols.
ModuleSpec module_spec;
module_spec.GetUUID() = kernel_uuid;
module_spec.GetArchitecture() = target.GetArchitecture();
// Lookup UUID locally, before attempting dsymForUUID like action
FileSpecList search_paths =
Target::GetDefaultDebugFileSearchPaths();
module_spec.GetSymbolFileSpec() =
PluginManager::LocateExecutableSymbolFile(module_spec,
search_paths);
if (module_spec.GetSymbolFileSpec()) {
ModuleSpec executable_module_spec =
PluginManager::LocateExecutableObjectFile(module_spec);
if (FileSystem::Instance().Exists(
executable_module_spec.GetFileSpec())) {
module_spec.GetFileSpec() =
executable_module_spec.GetFileSpec();
}
}
if (!module_spec.GetSymbolFileSpec() ||
!module_spec.GetSymbolFileSpec()) {
Status symbl_error;
PluginManager::DownloadObjectAndSymbolFile(module_spec,
symbl_error, true);
}
if (FileSystem::Instance().Exists(module_spec.GetFileSpec())) {
ModuleSP module_sp(new Module(module_spec));
if (module_sp.get() && module_sp->GetObjectFile()) {
// Get the current target executable
ModuleSP exe_module_sp(target.GetExecutableModule());
// Make sure you don't already have the right module loaded
// and they will be uniqued
if (exe_module_sp.get() != module_sp.get())
target.SetExecutableModule(module_sp, eLoadDependentsNo);
}
}
}
} else if (m_comm.RemoteIsDarwinKernel()) {
m_dyld_plugin_name =
DynamicLoaderDarwinKernel::GetPluginNameStatic();
if (kernel_load_addr != LLDB_INVALID_ADDRESS) {
m_kernel_load_addr = kernel_load_addr;
}
}
// Set the thread ID
UpdateThreadListIfNeeded();
SetID(1);
GetThreadList();
SetPrivateState(eStateStopped);
StreamSP async_strm_sp(target.GetDebugger().GetAsyncOutputStream());
if (async_strm_sp) {
const char *cstr;
if ((cstr = m_comm.GetKernelVersion()) != NULL) {
async_strm_sp->Printf("Version: %s\n", cstr);
async_strm_sp->Flush();
}
// if ((cstr = m_comm.GetImagePath ()) != NULL)
// {
// async_strm_sp->Printf ("Image Path:
// %s\n", cstr);
// async_strm_sp->Flush();
// }
}
} else {
error.SetErrorString("KDP_REATTACH failed");
}
} else {
error.SetErrorString("KDP_REATTACH failed");
}
} else {
error.SetErrorString("invalid reply port from UDP connection");
}
} else {
if (error.Success())
error.SetErrorStringWithFormat("failed to connect to '%s'",
remote_url.str().c_str());
}
if (error.Fail())
m_comm.Disconnect();
return error;
}
// Process Control
Status ProcessKDP::DoLaunch(Module *exe_module,
ProcessLaunchInfo &launch_info) {
Status error;
error.SetErrorString("launching not supported in kdp-remote plug-in");
return error;
}
Status
ProcessKDP::DoAttachToProcessWithID(lldb::pid_t attach_pid,
const ProcessAttachInfo &attach_info) {
Status error;
error.SetErrorString(
"attach to process by ID is not supported in kdp remote debugging");
return error;
}
Status
ProcessKDP::DoAttachToProcessWithName(const char *process_name,
const ProcessAttachInfo &attach_info) {
Status error;
error.SetErrorString(
"attach to process by name is not supported in kdp remote debugging");
return error;
}
void ProcessKDP::DidAttach(ArchSpec &process_arch) {
Process::DidAttach(process_arch);
Log *log = GetLog(KDPLog::Process);
LLDB_LOGF(log, "ProcessKDP::DidAttach()");
if (GetID() != LLDB_INVALID_PROCESS_ID) {
GetHostArchitecture(process_arch);
}
}
addr_t ProcessKDP::GetImageInfoAddress() { return m_kernel_load_addr; }
lldb_private::DynamicLoader *ProcessKDP::GetDynamicLoader() {
if (m_dyld_up.get() == NULL)
m_dyld_up.reset(DynamicLoader::FindPlugin(this, m_dyld_plugin_name));
return m_dyld_up.get();
}
Status ProcessKDP::WillResume() { return Status(); }
Status ProcessKDP::DoResume() {
Status error;
Log *log = GetLog(KDPLog::Process);
// Only start the async thread if we try to do any process control
if (!m_async_thread.IsJoinable())
StartAsyncThread();
bool resume = false;
// With KDP there is only one thread we can tell what to do
ThreadSP kernel_thread_sp(m_thread_list.FindThreadByProtocolID(g_kernel_tid));
if (kernel_thread_sp) {
const StateType thread_resume_state =
kernel_thread_sp->GetTemporaryResumeState();
LLDB_LOGF(log, "ProcessKDP::DoResume() thread_resume_state = %s",
StateAsCString(thread_resume_state));
switch (thread_resume_state) {
case eStateSuspended:
// Nothing to do here when a thread will stay suspended we just leave the
// CPU mask bit set to zero for the thread
LLDB_LOGF(log, "ProcessKDP::DoResume() = suspended???");
break;
case eStateStepping: {
lldb::RegisterContextSP reg_ctx_sp(
kernel_thread_sp->GetRegisterContext());
if (reg_ctx_sp) {
LLDB_LOGF(
log,
"ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep (true);");
reg_ctx_sp->HardwareSingleStep(true);
resume = true;
} else {
error.SetErrorStringWithFormat(
"KDP thread 0x%llx has no register context",
kernel_thread_sp->GetID());
}
} break;
case eStateRunning: {
lldb::RegisterContextSP reg_ctx_sp(
kernel_thread_sp->GetRegisterContext());
if (reg_ctx_sp) {
LLDB_LOGF(log, "ProcessKDP::DoResume () reg_ctx_sp->HardwareSingleStep "
"(false);");
reg_ctx_sp->HardwareSingleStep(false);
resume = true;
} else {
error.SetErrorStringWithFormat(
"KDP thread 0x%llx has no register context",
kernel_thread_sp->GetID());
}
} break;
default:
// The only valid thread resume states are listed above
llvm_unreachable("invalid thread resume state");
}
}
if (resume) {
LLDB_LOGF(log, "ProcessKDP::DoResume () sending resume");
if (m_comm.SendRequestResume()) {
m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncContinue);
SetPrivateState(eStateRunning);
} else
error.SetErrorString("KDP resume failed");
} else {
error.SetErrorString("kernel thread is suspended");
}
return error;
}
lldb::ThreadSP ProcessKDP::GetKernelThread() {
// KDP only tells us about one thread/core. Any other threads will usually
// be the ones that are read from memory by the OS plug-ins.
ThreadSP thread_sp(m_kernel_thread_wp.lock());
if (!thread_sp) {
thread_sp = std::make_shared<ThreadKDP>(*this, g_kernel_tid);
m_kernel_thread_wp = thread_sp;
}
return thread_sp;
}
bool ProcessKDP::DoUpdateThreadList(ThreadList &old_thread_list,
ThreadList &new_thread_list) {
// locker will keep a mutex locked until it goes out of scope
Log *log = GetLog(KDPLog::Thread);
LLDB_LOGV(log, "pid = {0}", GetID());
// Even though there is a CPU mask, it doesn't mean we can see each CPU
// individually, there is really only one. Lets call this thread 1.
ThreadSP thread_sp(
old_thread_list.FindThreadByProtocolID(g_kernel_tid, false));
if (!thread_sp)
thread_sp = GetKernelThread();
new_thread_list.AddThread(thread_sp);
return new_thread_list.GetSize(false) > 0;
}
void ProcessKDP::RefreshStateAfterStop() {
// Let all threads recover from stopping and do any clean up based on the
// previous thread state (if any).
m_thread_list.RefreshStateAfterStop();
}
Status ProcessKDP::DoHalt(bool &caused_stop) {
Status error;
if (m_comm.IsRunning()) {
if (m_destroy_in_process) {
// If we are attempting to destroy, we need to not return an error to Halt
// or DoDestroy won't get called. We are also currently running, so send
// a process stopped event
SetPrivateState(eStateStopped);
} else {
error.SetErrorString("KDP cannot interrupt a running kernel");
}
}
return error;
}
Status ProcessKDP::DoDetach(bool keep_stopped) {
Status error;
Log *log = GetLog(KDPLog::Process);
LLDB_LOGF(log, "ProcessKDP::DoDetach(keep_stopped = %i)", keep_stopped);
if (m_comm.IsRunning()) {
// We are running and we can't interrupt a running kernel, so we need to
// just close the connection to the kernel and hope for the best
} else {
// If we are going to keep the target stopped, then don't send the
// disconnect message.
if (!keep_stopped && m_comm.IsConnected()) {
const bool success = m_comm.SendRequestDisconnect();
if (log) {
if (success)
log->PutCString(
"ProcessKDP::DoDetach() detach packet sent successfully");
else
log->PutCString(
"ProcessKDP::DoDetach() connection channel shutdown failed");
}
m_comm.Disconnect();
}
}
StopAsyncThread();
m_comm.Clear();
SetPrivateState(eStateDetached);
ResumePrivateStateThread();
// KillDebugserverProcess ();
return error;
}
Status ProcessKDP::DoDestroy() {
// For KDP there really is no difference between destroy and detach
bool keep_stopped = false;
return DoDetach(keep_stopped);
}
// Process Queries
bool ProcessKDP::IsAlive() {
return m_comm.IsConnected() && Process::IsAlive();
}
// Process Memory
size_t ProcessKDP::DoReadMemory(addr_t addr, void *buf, size_t size,
Status &error) {
uint8_t *data_buffer = (uint8_t *)buf;
if (m_comm.IsConnected()) {
const size_t max_read_size = 512;
size_t total_bytes_read = 0;
// Read the requested amount of memory in 512 byte chunks
while (total_bytes_read < size) {
size_t bytes_to_read_this_request = size - total_bytes_read;
if (bytes_to_read_this_request > max_read_size) {
bytes_to_read_this_request = max_read_size;
}
size_t bytes_read = m_comm.SendRequestReadMemory(
addr + total_bytes_read, data_buffer + total_bytes_read,
bytes_to_read_this_request, error);
total_bytes_read += bytes_read;
if (error.Fail() || bytes_read == 0) {
return total_bytes_read;
}
}
return total_bytes_read;
}
error.SetErrorString("not connected");
return 0;
}
size_t ProcessKDP::DoWriteMemory(addr_t addr, const void *buf, size_t size,
Status &error) {
if (m_comm.IsConnected())
return m_comm.SendRequestWriteMemory(addr, buf, size, error);
error.SetErrorString("not connected");
return 0;
}
lldb::addr_t ProcessKDP::DoAllocateMemory(size_t size, uint32_t permissions,
Status &error) {
error.SetErrorString(
"memory allocation not supported in kdp remote debugging");
return LLDB_INVALID_ADDRESS;
}
Status ProcessKDP::DoDeallocateMemory(lldb::addr_t addr) {
Status error;
error.SetErrorString(
"memory deallocation not supported in kdp remote debugging");
return error;
}
Status ProcessKDP::EnableBreakpointSite(BreakpointSite *bp_site) {
if (bp_site->HardwareRequired())
return Status("Hardware breakpoints are not supported.");
if (m_comm.LocalBreakpointsAreSupported()) {
Status error;
if (!bp_site->IsEnabled()) {
if (m_comm.SendRequestBreakpoint(true, bp_site->GetLoadAddress())) {
bp_site->SetEnabled(true);
bp_site->SetType(BreakpointSite::eExternal);
} else {
error.SetErrorString("KDP set breakpoint failed");
}
}
return error;
}
return EnableSoftwareBreakpoint(bp_site);
}
Status ProcessKDP::DisableBreakpointSite(BreakpointSite *bp_site) {
if (m_comm.LocalBreakpointsAreSupported()) {
Status error;
if (bp_site->IsEnabled()) {
BreakpointSite::Type bp_type = bp_site->GetType();
if (bp_type == BreakpointSite::eExternal) {
if (m_destroy_in_process && m_comm.IsRunning()) {
// We are trying to destroy our connection and we are running
bp_site->SetEnabled(false);
} else {
if (m_comm.SendRequestBreakpoint(false, bp_site->GetLoadAddress()))
bp_site->SetEnabled(false);
else
error.SetErrorString("KDP remove breakpoint failed");
}
} else {
error = DisableSoftwareBreakpoint(bp_site);
}
}
return error;
}
return DisableSoftwareBreakpoint(bp_site);
}
void ProcessKDP::Clear() { m_thread_list.Clear(); }
Status ProcessKDP::DoSignal(int signo) {
Status error;
error.SetErrorString(
"sending signals is not supported in kdp remote debugging");
return error;
}
void ProcessKDP::Initialize() {
static llvm::once_flag g_once_flag;
llvm::call_once(g_once_flag, []() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(), CreateInstance,
DebuggerInitialize);
ProcessKDPLog::Initialize();
});
}
void ProcessKDP::DebuggerInitialize(lldb_private::Debugger &debugger) {
if (!PluginManager::GetSettingForProcessPlugin(
debugger, PluginProperties::GetSettingName())) {
const bool is_global_setting = true;
PluginManager::CreateSettingForProcessPlugin(
debugger, GetGlobalPluginProperties().GetValueProperties(),
"Properties for the kdp-remote process plug-in.", is_global_setting);
}
}
bool ProcessKDP::StartAsyncThread() {
Log *log = GetLog(KDPLog::Process);
LLDB_LOGF(log, "ProcessKDP::StartAsyncThread ()");
if (m_async_thread.IsJoinable())
return true;
llvm::Expected<HostThread> async_thread = ThreadLauncher::LaunchThread(
"<lldb.process.kdp-remote.async>", [this] { return AsyncThread(); });
if (!async_thread) {
LLDB_LOG_ERROR(GetLog(LLDBLog::Host), async_thread.takeError(),
"failed to launch host thread: {0}");
return false;
}
m_async_thread = *async_thread;
return m_async_thread.IsJoinable();
}
void ProcessKDP::StopAsyncThread() {
Log *log = GetLog(KDPLog::Process);
LLDB_LOGF(log, "ProcessKDP::StopAsyncThread ()");
m_async_broadcaster.BroadcastEvent(eBroadcastBitAsyncThreadShouldExit);
// Stop the stdio thread
if (m_async_thread.IsJoinable())
m_async_thread.Join(nullptr);
}
void *ProcessKDP::AsyncThread() {
const lldb::pid_t pid = GetID();
Log *log = GetLog(KDPLog::Process);
LLDB_LOGF(log,
"ProcessKDP::AsyncThread(pid = %" PRIu64 ") thread starting...",
pid);
ListenerSP listener_sp(Listener::MakeListener("ProcessKDP::AsyncThread"));
EventSP event_sp;
const uint32_t desired_event_mask =
eBroadcastBitAsyncContinue | eBroadcastBitAsyncThreadShouldExit;
if (listener_sp->StartListeningForEvents(
&m_async_broadcaster, desired_event_mask) == desired_event_mask) {
bool done = false;
while (!done) {
LLDB_LOGF(log,
"ProcessKDP::AsyncThread (pid = %" PRIu64
") listener.WaitForEvent (NULL, event_sp)...",
pid);
if (listener_sp->GetEvent(event_sp, std::nullopt)) {
uint32_t event_type = event_sp->GetType();
LLDB_LOGF(log,
"ProcessKDP::AsyncThread (pid = %" PRIu64
") Got an event of type: %d...",
pid, event_type);
// When we are running, poll for 1 second to try and get an exception
// to indicate the process has stopped. If we don't get one, check to
// make sure no one asked us to exit
bool is_running = false;
DataExtractor exc_reply_packet;
do {
switch (event_type) {
case eBroadcastBitAsyncContinue: {
is_running = true;
if (m_comm.WaitForPacketWithTimeoutMicroSeconds(
exc_reply_packet, 1 * USEC_PER_SEC)) {
ThreadSP thread_sp(GetKernelThread());
if (thread_sp) {
lldb::RegisterContextSP reg_ctx_sp(
thread_sp->GetRegisterContext());
if (reg_ctx_sp)
reg_ctx_sp->InvalidateAllRegisters();
static_cast<ThreadKDP *>(thread_sp.get())
->SetStopInfoFrom_KDP_EXCEPTION(exc_reply_packet);
}
// TODO: parse the stop reply packet
is_running = false;
SetPrivateState(eStateStopped);
} else {
// Check to see if we are supposed to exit. There is no way to
// interrupt a running kernel, so all we can do is wait for an
// exception or detach...
if (listener_sp->GetEvent(event_sp,
std::chrono::microseconds(0))) {
// We got an event, go through the loop again
event_type = event_sp->GetType();
}
}
} break;
case eBroadcastBitAsyncThreadShouldExit:
LLDB_LOGF(log,
"ProcessKDP::AsyncThread (pid = %" PRIu64
") got eBroadcastBitAsyncThreadShouldExit...",
pid);
done = true;
is_running = false;
break;
default:
LLDB_LOGF(log,
"ProcessKDP::AsyncThread (pid = %" PRIu64
") got unknown event 0x%8.8x",
pid, event_type);
done = true;
is_running = false;
break;
}
} while (is_running);
} else {
LLDB_LOGF(log,
"ProcessKDP::AsyncThread (pid = %" PRIu64
") listener.WaitForEvent (NULL, event_sp) => false",
pid);
done = true;
}
}
}
LLDB_LOGF(log, "ProcessKDP::AsyncThread(pid = %" PRIu64 ") thread exiting...",
pid);
m_async_thread.Reset();
return NULL;
}
class CommandObjectProcessKDPPacketSend : public CommandObjectParsed {
private:
OptionGroupOptions m_option_group;
OptionGroupUInt64 m_command_byte;
OptionGroupString m_packet_data;
Options *GetOptions() override { return &m_option_group; }
public:
CommandObjectProcessKDPPacketSend(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "process plugin packet send",
"Send a custom packet through the KDP protocol by "
"specifying the command byte and the packet "
"payload data. A packet will be sent with a "
"correct header and payload, and the raw result "
"bytes will be displayed as a string value. ",
NULL),
m_option_group(),
m_command_byte(LLDB_OPT_SET_1, true, "command", 'c', 0, eArgTypeNone,
"Specify the command byte to use when sending the KDP "
"request packet.",
0),
m_packet_data(LLDB_OPT_SET_1, false, "payload", 'p', 0, eArgTypeNone,
"Specify packet payload bytes as a hex ASCII string with "
"no spaces or hex prefixes.",
NULL) {
m_option_group.Append(&m_command_byte, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
m_option_group.Append(&m_packet_data, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1);
m_option_group.Finalize();
}
~CommandObjectProcessKDPPacketSend() override = default;
void DoExecute(Args &command, CommandReturnObject &result) override {
if (!m_command_byte.GetOptionValue().OptionWasSet()) {
result.AppendError(
"the --command option must be set to a valid command byte");
} else {
const uint64_t command_byte =
m_command_byte.GetOptionValue().GetValueAs<uint64_t>().value_or(0);
if (command_byte > 0 && command_byte <= UINT8_MAX) {
ProcessKDP *process =
(ProcessKDP *)m_interpreter.GetExecutionContext().GetProcessPtr();
if (process) {
const StateType state = process->GetState();
if (StateIsStoppedState(state, true)) {
std::vector<uint8_t> payload_bytes;
const char *ascii_hex_bytes_cstr =
m_packet_data.GetOptionValue().GetCurrentValue();
if (ascii_hex_bytes_cstr && ascii_hex_bytes_cstr[0]) {
StringExtractor extractor(ascii_hex_bytes_cstr);
const size_t ascii_hex_bytes_cstr_len =
extractor.GetStringRef().size();
if (ascii_hex_bytes_cstr_len & 1) {
result.AppendErrorWithFormat("payload data must contain an "
"even number of ASCII hex "
"characters: '%s'",
ascii_hex_bytes_cstr);
return;
}
payload_bytes.resize(ascii_hex_bytes_cstr_len / 2);
if (extractor.GetHexBytes(payload_bytes, '\xdd') !=
payload_bytes.size()) {
result.AppendErrorWithFormat("payload data must only contain "
"ASCII hex characters (no "
"spaces or hex prefixes): '%s'",
ascii_hex_bytes_cstr);
return;
}
}
Status error;
DataExtractor reply;
process->GetCommunication().SendRawRequest(
command_byte,
payload_bytes.empty() ? NULL : payload_bytes.data(),
payload_bytes.size(), reply, error);
if (error.Success()) {
// Copy the binary bytes into a hex ASCII string for the result
StreamString packet;
packet.PutBytesAsRawHex8(
reply.GetDataStart(), reply.GetByteSize(),
endian::InlHostByteOrder(), endian::InlHostByteOrder());
result.AppendMessage(packet.GetString());
result.SetStatus(eReturnStatusSuccessFinishResult);
return;
} else {
const char *error_cstr = error.AsCString();
if (error_cstr && error_cstr[0])
result.AppendError(error_cstr);
else
result.AppendErrorWithFormat("unknown error 0x%8.8x",
error.GetError());
return;
}
} else {
result.AppendErrorWithFormat("process must be stopped in order "
"to send KDP packets, state is %s",
StateAsCString(state));
}
} else {
result.AppendError("invalid process");
}
} else {
result.AppendErrorWithFormat("invalid command byte 0x%" PRIx64
", valid values are 1 - 255",
command_byte);
}
}
}
};
class CommandObjectProcessKDPPacket : public CommandObjectMultiword {
private:
public:
CommandObjectProcessKDPPacket(CommandInterpreter &interpreter)
: CommandObjectMultiword(interpreter, "process plugin packet",
"Commands that deal with KDP remote packets.",
NULL) {
LoadSubCommand(
"send",
CommandObjectSP(new CommandObjectProcessKDPPacketSend(interpreter)));
}
~CommandObjectProcessKDPPacket() override = default;
};
class CommandObjectMultiwordProcessKDP : public CommandObjectMultiword {
public:
CommandObjectMultiwordProcessKDP(CommandInterpreter &interpreter)
: CommandObjectMultiword(
interpreter, "process plugin",
"Commands for operating on a ProcessKDP process.",
"process plugin <subcommand> [<subcommand-options>]") {
LoadSubCommand("packet", CommandObjectSP(new CommandObjectProcessKDPPacket(
interpreter)));
}
~CommandObjectMultiwordProcessKDP() override = default;
};
CommandObject *ProcessKDP::GetPluginCommandObject() {
if (!m_command_sp)
m_command_sp = std::make_shared<CommandObjectMultiwordProcessKDP>(
GetTarget().GetDebugger().GetCommandInterpreter());
return m_command_sp.get();
}