panic.cpp

/*
panic.cpp

Copyright (c) 29 Yann BOUCHER (yann)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

*/

#include "panic.hpp"

#include <stdio.h>
#include <stdarg.h>

#include "utils/defs.hpp"
#include "utils/demangle.hpp"
#include "utils/nop.hpp"
#include "utils/stlutils.hpp"

#include "debug/stack-trace.hpp"
#include "debug/dissasembly.hpp"

#include "elf/symbol_table.hpp"
#include "mem/memmap.hpp"
#include "drivers/sound/beep.hpp"

#include "terminal/terminal.hpp"

#ifdef ARCH_i686
#include "i686/pc/devices/speaker.hpp"
#include "i686/interrupts/interrupts.hpp"
#include "i686/cpu/registers.hpp"
#endif

#include "halt.hpp"

registers panic_regs;
bool panic_use_exception_frame = false;

std::vector<TraceEntry> exception_stack_frame;

extern "C" void isr_common_stub();
extern "C" void irq_common_stub();
extern "C" void kmain();

size_t trace_offset(const std::vector<TraceEntry>& trace)
{
    size_t offset = 0;
#ifdef ARCH_i686
    while (offset < trace.size() &&
           trace[offset].address != (uintptr_t)&isr_common_stub + 31 &&
           trace[offset].address != (uintptr_t)&irq_common_stub + 31 &&
           (trace[offset].sym_info ? trace[offset].sym_info->offset != (uintptr_t)&panic : true))
    {
        ++offset;
    }

    if (offset == trace.size())
    {
        offset = 0;
    }
    else
    {
        ++offset;
    }
#endif

    return offset;
}

void print_stack_symbols()
{
    auto trace = (panic_use_exception_frame?exception_stack_frame:trace_stack(nullptr, 0));

    // Discard the first function call to kmain, saves space
    for (size_t i = trace_offset(trace), cnt = 1; i < trace.size(); ++i, ++cnt)
    {

        if (trace[i].sym_info)
        {
            if (trace[i].sym_info->offset == (uintptr_t)kmain)
            {
                kprintf("\n"); break; // it's pointless to show stacktrace after kmain
            }

            kprintf("#%d   0x%x in %s", cnt, trace[i].address, demangle(trace[i].sym_info->name));
        }
        else if (trace[i].address < KERNEL_VIRTUAL_BASE)
        {
            kprintf("#%d    0x%x in <userspace>", cnt, trace[i].address);
        }
        else
        {
            kprintf("#%d    0x%x in ????", cnt, trace[i].address);
        }

        if (i < trace.size()-1) // don't print a newline after the last entry, wastes space otherwise
        {
            kprintf("\n");
        }
    }
}

void print_disassembly()
{
    if (!Memory::is_mapped((void*)panic_regs.eip))
    {
        kprintf("No disassembly available, eip is at an unmapped address : \n");
        return;
    }


    kprintf("Disassembly : \n");

    size_t dump_len = 7;

    auto func_base = elf::kernel_symbol_table.get_function(panic_regs.eip);
    const uint8_t* base_ip;
    if (!func_base)
    {
        base_ip = (uint8_t*)panic_regs.eip;
        dump_len /= 2; // show half as much data in this case
    }
    else
    {
        base_ip = (uint8_t*)func_base->offset;
        const uint8_t* target_ip = (uint8_t*)panic_regs.eip;
        while (next_ins(base_ip, dump_len/2) < target_ip)
        {
            base_ip = next_ins(base_ip);
        }
    }

    const uint8_t* ip = base_ip;

    for (size_t i { 0 }; i < dump_len; ++i)
    {
        DisasmInfo info = get_disasm(ip);
        kpp::string bytes = join(map<uint8_t, kpp::string>(info.bytes, [](uint8_t c){return kpp::to_hex_string(c);}), " ");
        if (ip == (uint8_t*)panic_regs.eip)
        {
            kprintf("->  ");
        }
        else
        {
            kprintf("    ");
        }
        kprintf("%s (%s)\n", info.str.c_str(), bytes.c_str());
        ip += info.len;
    }
}

void panic(const char *fmt, ...)
{
    cli();

    term_data().clear();
    term_data().push_color({0xffffff, 0xaa0000});

    term().clear();
    term().set_title(U"KERNEL PANIC", {0xff5555, 0xffffff});

    putc_serial = true;

    beep(300);

    puts("KERNEL PANIC : ");

    {
        va_list va;
        va_start(va, fmt);
        tfp_format(nullptr, [](void*, char c){putchar(c);}, fmt, va);
        va_end(va);
    }

    kprintf("\n");

    dump(&panic_regs);

    kprintf("\n");

    print_disassembly();

    kprintf("\nStack:\n");

    print_stack_symbols();

    term().enable();
    term().scroll_bottom();
    term().draw();

    int i = 10000;
    while (--i) nop();

    //FIXME : Speaker::stop();

    halt();
}

void set_exception_frame_ptr(void *ptr)
{
    if (ptr) exception_stack_frame = trace_stack(ptr, 0);
    else exception_stack_frame.clear();
}