Kernel+LibCoreDump: Implement more x86_64 coredump functionality

Author: gunnarbeutner

Kernel/CoreDump.cpp

@@ -78,7 +78,11 @@ KResult CoreDump::write_elf_header()
     elf_file_header.e_ident[EI_MAG1] = 'E';
     elf_file_header.e_ident[EI_MAG2] = 'L';
     elf_file_header.e_ident[EI_MAG3] = 'F';
+#if ARCH(I386)
     elf_file_header.e_ident[EI_CLASS] = ELFCLASS32;
+#else
+    elf_file_header.e_ident[EI_CLASS] = ELFCLASS64;
+#endif
     elf_file_header.e_ident[EI_DATA] = ELFDATA2LSB;
     elf_file_header.e_ident[EI_VERSION] = EV_CURRENT;
     elf_file_header.e_ident[EI_OSABI] = 0; // ELFOSABI_NONE
@@ -90,7 +94,11 @@ KResult CoreDump::write_elf_header()
     elf_file_header.e_ident[EI_PAD + 5] = 0;
     elf_file_header.e_ident[EI_PAD + 6] = 0;
     elf_file_header.e_type = ET_CORE;
+#if ARCH(I386)
     elf_file_header.e_machine = EM_386;
+#else
+    elf_file_header.e_machine = EM_X86_64;
+#endif
     elf_file_header.e_version = 1;
     elf_file_header.e_entry = 0;
     elf_file_header.e_phoff = sizeof(ElfW(Ehdr));

Userland/Libraries/LibCoreDump/Backtrace.cpp

@@ -43,6 +43,10 @@ static const ELFObjectInfo* object_info_for_region(const ELF::Core::MemoryRegion
         return nullptr;
 
     auto image = make<ELF::Image>(file_or_error.value()->bytes());
+#if !ARCH(I386)
+    // FIXME: Fix LibDebug
+    return nullptr;
+#endif
     auto info = make<ELFObjectInfo>(file_or_error.release_value(), make<Debug::DebugInfo>(move(image)));
     auto* info_ptr = info.ptr();
     s_debug_info_cache.set(path, move(info));
@@ -52,30 +56,33 @@ static const ELFObjectInfo* object_info_for_region(const ELF::Core::MemoryRegion
 Backtrace::Backtrace(const Reader& coredump, const ELF::Core::ThreadInfo& thread_info)
     : m_thread_info(move(thread_info))
 {
+    FlatPtr* bp;
+    FlatPtr* ip;
 #if ARCH(I386)
-    uint32_t* ebp = (uint32_t*)m_thread_info.regs.ebp;
-    uint32_t* eip = (uint32_t*)m_thread_info.regs.eip;
+    bp = (FlatPtr*)m_thread_info.regs.ebp;
+    ip = (FlatPtr*)m_thread_info.regs.eip;
+#else
+    bp = (FlatPtr*)m_thread_info.regs.rbp;
+    ip = (FlatPtr*)m_thread_info.regs.rip;
+#endif
+
     bool first_frame = true;
-    while (ebp && eip) {
+    while (bp && ip) {
         // We use eip - 1 because the return address from a function frame
         // is the instruction that comes after the 'call' instruction.
         // However, because the first frame represents the faulting
         // instruction rather than the return address we don't subtract
         // 1 there.
-        VERIFY((FlatPtr)eip > 0);
-        add_entry(coredump, (FlatPtr)eip - (first_frame ? 0 : 1));
+        VERIFY((FlatPtr)ip > 0);
+        add_entry(coredump, (FlatPtr)ip - (first_frame ? 0 : 1));
         first_frame = false;
-        auto next_eip = coredump.peek_memory((FlatPtr)(ebp + 1));
-        auto next_ebp = coredump.peek_memory((FlatPtr)(ebp));
-        if (!next_eip.has_value() || !next_ebp.has_value())
+        auto next_ip = coredump.peek_memory((FlatPtr)(bp + 1));
+        auto next_bp = coredump.peek_memory((FlatPtr)(bp));
+        if (!next_ip.has_value() || !next_bp.has_value())
             break;
-        eip = (uint32_t*)next_eip.value();
-        ebp = (uint32_t*)next_ebp.value();
+        ip = (FlatPtr*)next_ip.value();
+        bp = (FlatPtr*)next_bp.value();
     }
-#else
-    (void)coredump;
-    TODO();
-#endif
 }
 
 Backtrace::~Backtrace()
@@ -96,9 +103,14 @@ void Backtrace::add_entry(const Reader& coredump, FlatPtr eip)
     if (!object_info)
         return;
 
+#if ARCH(I386)
     auto function_name = object_info->debug_info->elf().symbolicate(eip - region->region_start);
     auto source_position = object_info->debug_info->get_source_position_with_inlines(eip - region->region_start);
-
+#else
+    // FIXME: Fix symbolication.
+    auto function_name = "";
+    Debug::DebugInfo::SourcePositionWithInlines source_position;
+#endif
     m_entries.append({ eip, object_name, function_name, source_position });
 }
 

Userland/Libraries/LibCoreDump/Reader.cpp

@@ -106,15 +106,15 @@ bool Reader::NotesEntryIterator::at_end() const
     return type() == ELF::Core::NotesEntryHeader::Type::Null;
 }
 
-Optional<uint32_t> Reader::peek_memory(FlatPtr address) const
+Optional<FlatPtr> Reader::peek_memory(FlatPtr address) const
 {
     const auto* region = region_containing(address);
     if (!region)
         return {};
 
     FlatPtr offset_in_region = address - region->region_start;
     const char* region_data = image().program_header(region->program_header_index).raw_data();
-    return *(const uint32_t*)(&region_data[offset_in_region]);
+    return *(const FlatPtr*)(&region_data[offset_in_region]);
 }
 
 const JsonObject Reader::process_info() const

Userland/Libraries/LibCoreDump/Reader.h

@@ -31,7 +31,7 @@ class Reader {
 
     const ELF::Image& image() const { return m_coredump_image; }
 
-    Optional<uint32_t> peek_memory(FlatPtr address) const;
+    Optional<FlatPtr> peek_memory(FlatPtr address) const;
     const ELF::Core::MemoryRegionInfo* region_containing(FlatPtr address) const;
 
     struct LibraryData {