--- /dev/null
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2009 Free Software Foundation, Inc.
+ *
+ * GRUB is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef GRUB_BACKTRACE_HEADER
+#define GRUB_BACKTRACE_HEADER 1
+
+void grub_backtrace (void);
+void grub_backtrace_pointer (void *ptr);
+
+#endif
--- /dev/null
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2009 Free Software Foundation, Inc.
+ *
+ * GRUB is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/misc.h>
+#include <grub/command.h>
+#include <grub/err.h>
+#include <grub/dl.h>
+#include <grub/mm.h>
+#include <grub/term.h>
+#include <grub/backtrace.h>
+
+#define MAX_STACK_FRAME 102400
+
+struct idt_descriptor
+{
+ grub_uint16_t limit;
+ void *base;
+} __attribute__ ((packed));
+
+#define GRUB_IDT_ENTRY_TYPE_PRESENT 0x80
+#define GRUB_IDT_ENTRY_TYPE_NOT_PRESENT 0x00
+#define GRUB_IDT_ENTRY_TYPE_RING0 0x00
+#define GRUB_IDT_ENTRY_TYPE_TRAP32 0x0f
+
+struct idt_entry
+{
+ grub_uint16_t addr_low;
+ grub_uint16_t segment;
+ grub_uint8_t unused;
+ grub_uint8_t type;
+ grub_uint16_t addr_high;
+} __attribute__ ((packed));
+
+void
+print_address (void *addr)
+{
+ const char *name;
+ int section;
+ grub_off_t off;
+ auto int hook (grub_dl_t mod);
+ int hook (grub_dl_t mod)
+ {
+ grub_dl_segment_t segment;
+ for (segment = mod->segment; segment; segment = segment->next)
+ if (segment->addr <= addr && (grub_uint8_t *) segment->addr
+ + segment->size > (grub_uint8_t *) addr)
+ {
+ name = mod->name;
+ section = segment->section;
+ off = (grub_uint8_t *) addr - (grub_uint8_t *) segment->addr;
+ return 1;
+ }
+ return 0;
+ }
+
+ name = NULL;
+ grub_dl_iterate (hook);
+ if (name)
+ grub_printf ("%s.%x+%lx", name, section, (unsigned long) off);
+ else
+ grub_printf ("%p", addr);
+}
+
+void
+grub_backtrace_pointer (void *ebp)
+{
+ void *ptr, *nptr;
+ unsigned i;
+
+ ptr = ebp;
+ while (1)
+ {
+ grub_printf ("%p: ", ptr);
+ print_address (*(void **) (ptr + sizeof (void *)));
+ grub_printf (" (");
+ for (i = 0; i < 2; i++)
+ grub_printf ("%p,", *(void **)
+ (ptr + (i + 2) * sizeof (void *)));
+ grub_printf ("%p", *(void **)
+ (ptr + (i + 2) * sizeof (void *)));
+ grub_printf (")\n");
+ nptr = *(void **)ptr;
+ if (nptr < ptr || (void **) nptr - (void **) ptr > MAX_STACK_FRAME
+ || nptr == ptr)
+ {
+ grub_printf ("Invalid stack frame at %p (%p)\n", ptr, nptr);
+ break;
+ }
+ ptr = nptr;
+ }
+}
+
+void
+grub_interrupt_handler_real (void *ret, void *ebp)
+{
+ grub_printf ("Unhandled exception at ");
+ print_address (ret);
+ grub_printf ("\n");
+ grub_backtrace_pointer (ebp);
+ grub_abort ();
+}
+
+
+void
+grub_backtrace (void)
+{
+#ifdef __x86_64__
+ asm volatile ("movq %rbp, %rdi\n"
+ "call grub_backtrace_pointer");
+#else
+ asm volatile ("movl %ebp, %eax\n"
+ "call grub_backtrace_pointer");
+#endif
+}
+
+static grub_err_t
+grub_cmd_backtrace (grub_command_t cmd __attribute__ ((unused)),
+ int argc __attribute__ ((unused)),
+ char **args __attribute__ ((unused)))
+{
+ grub_backtrace ();
+ return 0;
+}
+
+#define NUM_INTERRUPTS 0x20
+
+void grub_int_handler (void);
+
+struct idt_descriptor idt_desc;
+
+static grub_err_t
+setup_interrupts (void)
+{
+ struct idt_entry *idt_table;
+ unsigned long i;
+ grub_uint16_t seg;
+ idt_table = grub_memalign (0x10, NUM_INTERRUPTS * sizeof (struct idt_entry));
+ if (!idt_table)
+ return grub_errno;
+ idt_desc.base = idt_table;
+ idt_desc.limit = NUM_INTERRUPTS;
+
+ asm volatile ("xorl %%eax, %%eax\n"
+ "mov %%cs, %%ax\n" :"=a" (seg));
+
+ for (i = 0; i < NUM_INTERRUPTS; i++)
+ {
+ idt_table[i].addr_low = ((grub_addr_t) grub_int_handler) & 0xffff;
+ idt_table[i].addr_high = ((grub_addr_t) grub_int_handler) >> 16;
+ idt_table[i].unused = 0;
+ idt_table[i].segment = seg;
+ idt_table[i].type = GRUB_IDT_ENTRY_TYPE_PRESENT
+ | GRUB_IDT_ENTRY_TYPE_RING0 | GRUB_IDT_ENTRY_TYPE_TRAP32;
+ }
+
+ asm volatile ("lidt %0" : : "m" (idt_desc));
+
+ return GRUB_ERR_NONE;
+}
+
+static grub_command_t cmd;
+
+GRUB_MOD_INIT(backtrace)
+{
+ grub_err_t err;
+ err = setup_interrupts();
+ if (err)
+ {
+ grub_print_error ();
+ grub_errno = GRUB_ERR_NONE;
+ }
+ cmd = grub_register_command ("backtrace", grub_cmd_backtrace,
+ 0, "Print backtrace.");
+}
+
+GRUB_MOD_FINI(backtrace)
+{
+ grub_unregister_command (cmd);
+}
projects / thirdparty / grub.git / commitdiff
