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Kernel: Update cryptically-named functions related to symbolication

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This commit is contained in:
Andreas Kling 2020-04-08 13:30:50 +02:00
parent 348e209eb5
commit dc7340332d
6 changed files with 71 additions and 73 deletions
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101
Kernel/KSyms.cpp
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@ -34,11 +34,12 @@
namespace Kernel {
static KSym* s_ksyms;
u32 ksym_lowest_address = 0xffffffff;
u32 ksym_highest_address = 0;
u32 ksym_count = 0;
bool ksyms_ready = false;
FlatPtr g_lowest_kernel_symbol_address = 0xffffffff;
FlatPtr g_highest_kernel_symbol_address = 0;
bool g_kernel_symbols_available = false;
static KernelSymbol* s_symbols;
static size_t s_symbol_count = 0;
static u8 parse_hex_digit(char nibble)
{
@ -50,43 +51,44 @@ static u8 parse_hex_digit(char nibble)
u32 address_for_kernel_symbol(const StringView& name)
{
for (unsigned i = 0; i < ksym_count; ++i) {
if (!strncmp(name.characters_without_null_termination(), s_ksyms[i].name, name.length()))
return s_ksyms[i].address;
for (size_t i = 0; i < s_symbol_count; ++i) {
if (!strncmp(name.characters_without_null_termination(), s_symbols[i].name, name.length()))
return s_symbols[i].address;
}
return 0;
}
const KSym* ksymbolicate(u32 address)
const KernelSymbol* symbolicate_kernel_address(u32 address)
{
if (address < ksym_lowest_address || address > ksym_highest_address)
if (address < g_lowest_kernel_symbol_address || address > g_highest_kernel_symbol_address)
return nullptr;
for (unsigned i = 0; i < ksym_count; ++i) {
if (address < s_ksyms[i + 1].address)
return &s_ksyms[i];
for (unsigned i = 0; i < s_symbol_count; ++i) {
if (address < s_symbols[i + 1].address)
return &s_symbols[i];
}
return nullptr;
}
static void load_ksyms_from_data(const ByteBuffer& buffer)
static void load_kernel_sybols_from_data(const ByteBuffer& buffer)
{
ksym_lowest_address = 0xffffffff;
ksym_highest_address = 0;
g_lowest_kernel_symbol_address = 0xffffffff;
g_highest_kernel_symbol_address = 0;
auto* bufptr = (const char*)buffer.data();
auto* start_of_name = bufptr;
u32 address = 0;
FlatPtr address = 0;
for (unsigned i = 0; i < 8; ++i)
ksym_count = (ksym_count << 4) | parse_hex_digit(*(bufptr++));
s_ksyms = static_cast<KSym*>(kmalloc_eternal(sizeof(KSym) * ksym_count));
for (size_t i = 0; i < 8; ++i)
s_symbol_count = (s_symbol_count << 4) | parse_hex_digit(*(bufptr++));
s_symbols = static_cast<KernelSymbol*>(kmalloc_eternal(sizeof(KernelSymbol) * s_symbol_count));
++bufptr; // skip newline
klog() << "Loading ksyms...";
klog() << "Loading kernel symbol table...";
unsigned current_ksym_index = 0;
size_t current_symbol_index = 0;
while (bufptr < buffer.end_pointer()) {
for (unsigned i = 0; i < 8; ++i)
for (size_t i = 0; i < 8; ++i)
address = (address << 4) | parse_hex_digit(*(bufptr++));
bufptr += 3;
start_of_name = bufptr;
@ -95,23 +97,22 @@ static void load_ksyms_from_data(const ByteBuffer& buffer)
break;
}
}
auto& ksym = s_ksyms[current_ksym_index];
auto& ksym = s_symbols[current_symbol_index];
ksym.address = address;
char* name = static_cast<char*>(kmalloc_eternal((bufptr - start_of_name) + 1));
memcpy(name, start_of_name, bufptr - start_of_name);
name[bufptr - start_of_name] = '\0';
ksym.name = name;
if (ksym.address < ksym_lowest_address)
ksym_lowest_address = ksym.address;
if (ksym.address > ksym_highest_address)
ksym_highest_address = ksym.address;
if (ksym.address < g_lowest_kernel_symbol_address)
g_lowest_kernel_symbol_address = ksym.address;
if (ksym.address > g_highest_kernel_symbol_address)
g_highest_kernel_symbol_address = ksym.address;
++bufptr;
++current_ksym_index;
++current_symbol_index;
}
klog() << "ok";
ksyms_ready = true;
g_kernel_symbols_available = true;
}
[[gnu::noinline]] void dump_backtrace_impl(u32 ebp, bool use_ksyms)
@ -123,7 +124,7 @@ static void load_ksyms_from_data(const ByteBuffer& buffer)
return;
}
#endif
if (use_ksyms && !ksyms_ready) {
if (use_ksyms && !g_kernel_symbols_available) {
hang();
return;
}
@ -133,32 +134,32 @@ static void load_ksyms_from_data(const ByteBuffer& buffer)
elf_bundle = Process::current->elf_bundle();
struct RecognizedSymbol {
u32 address;
const KSym* ksym;
FlatPtr address;
const KernelSymbol* symbol { nullptr };
};
int max_recognized_symbol_count = 256;
size_t max_recognized_symbol_count = 256;
RecognizedSymbol recognized_symbols[max_recognized_symbol_count];
int recognized_symbol_count = 0;
size_t recognized_symbol_count = 0;
if (use_ksyms) {
for (u32* stack_ptr = (u32*)ebp;
for (FlatPtr* stack_ptr = (FlatPtr*)ebp;
(Process::current ? Process::current->validate_read_from_kernel(VirtualAddress(stack_ptr), sizeof(void*) * 2) : 1) && recognized_symbol_count < max_recognized_symbol_count; stack_ptr = (u32*)*stack_ptr) {
u32 retaddr = stack_ptr[1];
recognized_symbols[recognized_symbol_count++] = { retaddr, ksymbolicate(retaddr) };
FlatPtr retaddr = stack_ptr[1];
recognized_symbols[recognized_symbol_count++] = { retaddr, symbolicate_kernel_address(retaddr) };
}
} else {
for (u32* stack_ptr = (u32*)ebp;
for (FlatPtr* stack_ptr = (FlatPtr*)ebp;
(Process::current ? Process::current->validate_read_from_kernel(VirtualAddress(stack_ptr), sizeof(void*) * 2) : 1); stack_ptr = (u32*)*stack_ptr) {
u32 retaddr = stack_ptr[1];
FlatPtr retaddr = stack_ptr[1];
dbg() << String::format("%x", retaddr) << " (next: " << String::format("%x", (stack_ptr ? (u32*)*stack_ptr : 0)) << ")";
}
return;
}
ASSERT(recognized_symbol_count <= max_recognized_symbol_count);
for (int i = 0; i < recognized_symbol_count; ++i) {
for (size_t i = 0; i < recognized_symbol_count; ++i) {
auto& symbol = recognized_symbols[i];
if (!symbol.address)
break;
if (!symbol.ksym) {
if (!symbol.symbol) {
if (elf_bundle && elf_bundle->elf_loader->has_symbols()) {
dbg() << String::format("%p", symbol.address) << " " << elf_bundle->elf_loader->symbolicate(symbol.address);
} else {
@ -166,11 +167,11 @@ static void load_ksyms_from_data(const ByteBuffer& buffer)
}
continue;
}
unsigned offset = symbol.address - symbol.ksym->address;
if (symbol.ksym->address == ksym_highest_address && offset > 4096)
size_t offset = symbol.address - symbol.symbol->address;
if (symbol.symbol->address == g_highest_kernel_symbol_address && offset > 4096)
dbg() << String::format("%p", symbol.address);
else
dbg() << String::format("%p", symbol.address) << " " << demangle(symbol.ksym->name) << " +" << offset;
dbg() << String::format("%p", symbol.address) << " " << demangle(symbol.symbol->name) << " +" << offset;
}
}
@ -181,20 +182,20 @@ void dump_backtrace()
return;
TemporaryChange change(in_dump_backtrace, true);
TemporaryChange disable_kmalloc_stacks(g_dump_kmalloc_stacks, false);
u32 ebp;
FlatPtr ebp;
asm volatile("movl %%ebp, %%eax"
: "=a"(ebp));
dump_backtrace_impl(ebp, ksyms_ready);
dump_backtrace_impl(ebp, g_kernel_symbols_available);
}
void load_ksyms()
void load_kernel_symbol_table()
{
auto result = VFS::the().open("/res/kernel.map", O_RDONLY, 0, VFS::the().root_custody());
ASSERT(!result.is_error());
auto description = result.value();
auto buffer = description->read_entire_file();
ASSERT(buffer);
load_ksyms_from_data(buffer);
load_kernel_sybols_from_data(buffer);
}
}