freebsd-skq/sys/powerpc/include/db_machdep.h
jhibbits 560fc64981 Fix PPC symbol resolution
Summary:
There were 2 issues that were preventing correct symbol resolution
on PowerPC/pseries:

1- memory corruption at chrp_attach() - this caused the inital
   part of the symbol table to become zeroed, which would cause
   the kernel linker to fail to parse it.
   (this was probably zeroing out other memory parts as well)

2- DDB symbol resolution wasn't working because symtab contained
   not relocated addresses but it was given relocated offsets.
   Although relocating the symbol table fixed this, it broke the
   linker, that already handled this case.
   Thus, the fix for this consists in adding a new DDB macro:
   DB_STOFFS(offs) that converts a (potentially) relocated offset
   into one that can be compared with symbol table values.

PR:		227093
Submitted by:	Leandro Lupori <leandro.lupori_gmail.com>
Differential Revision: https://reviews.freebsd.org/D15372
2018-05-10 03:59:48 +00:00

93 lines
2.8 KiB
C

/*-
* Mach Operating System
* Copyright (c) 1992 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*
* $OpenBSD: db_machdep.h,v 1.2 1997/03/21 00:48:48 niklas Exp $
* $NetBSD: db_machdep.h,v 1.4.22.1 2000/08/05 11:10:43 wiz Exp $
* $FreeBSD$
*/
/*
* Machine-dependent defines for new kernel debugger.
*/
#ifndef _POWERPC_DB_MACHDEP_H_
#define _POWERPC_DB_MACHDEP_H_
#include <vm/vm_param.h>
#include <machine/elf.h>
#define DB_ELF_SYMBOLS
#define DB_ELFSIZE __ELF_WORD_SIZE
typedef vm_offset_t db_addr_t; /* address - unsigned */
typedef intptr_t db_expr_t; /* expression - signed */
#define PC_REGS(regs) ((db_addr_t)kdb_thrctx->pcb_lr)
#define BKPT_INST 0x7C810808 /* breakpoint instruction */
#define BKPT_SIZE (4) /* size of breakpoint inst */
#define BKPT_SET(inst) (BKPT_INST)
#define db_clear_single_step kdb_cpu_clear_singlestep
#define db_set_single_step kdb_cpu_set_singlestep
#if 0
#define SR_SINGLESTEP 0x400
#define db_clear_single_step(regs) ((regs)->msr &= ~SR_SINGLESTEP)
#define db_set_single_step(regs) ((regs)->msr |= SR_SINGLESTEP)
#endif
#define T_BREAKPOINT 0xffff
#define IS_BREAKPOINT_TRAP(type, code) ((type) == T_BREAKPOINT)
#define T_WATCHPOINT 0xeeee
#ifdef T_WATCHPOINT
#define IS_WATCHPOINT_TRAP(type, code) ((type) == T_WATCHPOINT)
#else
#define IS_WATCHPOINT_TRAP(type, code) 0
#endif
#define M_RTS 0xfc0007fe
#define I_RTS 0x4c000020
#define M_BC 0xfc000000
#define I_BC 0x40000000
#define M_B 0xfc000000
#define I_B 0x50000000
#define M_RFI 0xfc0007fe
#define I_RFI 0x4c000064
#define inst_trap_return(ins) (((ins)&M_RFI) == I_RFI)
#define inst_return(ins) (((ins)&M_RTS) == I_RTS)
#define inst_call(ins) (((ins)&M_BC ) == I_BC || \
((ins)&M_B ) == I_B )
#define inst_load(ins) 0
#define inst_store(ins) 0
#ifdef __powerpc64__
#define DB_STOFFS(offs) ((offs) & ~DMAP_BASE_ADDRESS)
#endif
#endif /* _POWERPC_DB_MACHDEP_H_ */