123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264 |
- /* libunwind - a platform-independent unwind library
- Copyright (C) 2008 CodeSourcery
- Copyright 2011 Linaro Limited
- This file is part of libunwind.
- 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 "unwind_i.h"
- #include "offsets.h"
- #include "ex_tables.h"
- #include <signal.h>
- #define arm_exidx_step UNW_OBJ(arm_exidx_step)
- static inline int
- arm_exidx_step (struct cursor *c)
- {
- unw_word_t old_ip, old_cfa;
- uint8_t buf[32];
- int ret;
- old_ip = c->dwarf.ip;
- old_cfa = c->dwarf.cfa;
- /* mark PC unsaved */
- c->dwarf.loc[UNW_ARM_R15] = DWARF_NULL_LOC;
- if ((ret = tdep_find_proc_info (&c->dwarf, c->dwarf.ip, 1)) < 0)
- return ret;
- if (c->dwarf.pi.format != UNW_INFO_FORMAT_ARM_EXIDX)
- return -UNW_ENOINFO;
- ret = arm_exidx_extract (&c->dwarf, buf);
- if (ret == -UNW_ESTOPUNWIND)
- return 0;
- else if (ret < 0)
- return ret;
- ret = arm_exidx_decode (buf, ret, &c->dwarf);
- if (ret < 0)
- return ret;
- if (c->dwarf.ip == old_ip && c->dwarf.cfa == old_cfa)
- {
- Dprintf ("%s: ip and cfa unchanged; stopping here (ip=0x%lx)\n",
- __FUNCTION__, (long) c->dwarf.ip);
- return -UNW_EBADFRAME;
- }
- return (c->dwarf.ip == 0) ? 0 : 1;
- }
- PROTECTED int
- unw_handle_signal_frame (unw_cursor_t *cursor)
- {
- struct cursor *c = (struct cursor *) cursor;
- int ret;
- unw_word_t sc_addr, sp, sp_addr = c->dwarf.cfa;
- struct dwarf_loc sp_loc = DWARF_LOC (sp_addr, 0);
- if ((ret = dwarf_get (&c->dwarf, sp_loc, &sp)) < 0)
- return -UNW_EUNSPEC;
- /* Obtain signal frame type (non-RT or RT). */
- ret = unw_is_signal_frame (cursor);
- /* Save the SP and PC to be able to return execution at this point
- later in time (unw_resume). */
- c->sigcontext_sp = c->dwarf.cfa;
- c->sigcontext_pc = c->dwarf.ip;
- /* Since kernel version 2.6.18 the non-RT signal frame starts with a
- ucontext while the RT signal frame starts with a siginfo, followed
- by a sigframe whose first element is an ucontext.
- Prior 2.6.18 the non-RT signal frame starts with a sigcontext while
- the RT signal frame starts with two pointers followed by a siginfo
- and an ucontext. The first pointer points to the start of the siginfo
- structure and the second one to the ucontext structure. */
- if (ret == 1)
- {
- /* Handle non-RT signal frames. Check if the first word on the stack
- is the magic number. */
- if (sp == 0x5ac3c35a)
- {
- c->sigcontext_format = ARM_SCF_LINUX_SIGFRAME;
- sc_addr = sp_addr + LINUX_UC_MCONTEXT_OFF;
- }
- else
- {
- c->sigcontext_format = ARM_SCF_LINUX_OLD_SIGFRAME;
- sc_addr = sp_addr;
- }
- c->sigcontext_addr = sp_addr;
- }
- else if (ret == 2)
- {
- /* Handle RT signal frames. Check if the first word on the stack is a
- pointer to the siginfo structure. */
- if (sp == sp_addr + 8)
- {
- c->sigcontext_format = ARM_SCF_LINUX_OLD_RT_SIGFRAME;
- c->sigcontext_addr = sp_addr + 8 + sizeof (siginfo_t);
- }
- else
- {
- c->sigcontext_format = ARM_SCF_LINUX_RT_SIGFRAME;
- c->sigcontext_addr = sp_addr + sizeof (siginfo_t);
- }
- sc_addr = c->sigcontext_addr + LINUX_UC_MCONTEXT_OFF;
- }
- else
- return -UNW_EUNSPEC;
- /* Update the dwarf cursor.
- Set the location of the registers to the corresponding addresses of the
- uc_mcontext / sigcontext structure contents. */
- c->dwarf.loc[UNW_ARM_R0] = DWARF_LOC (sc_addr + LINUX_SC_R0_OFF, 0);
- c->dwarf.loc[UNW_ARM_R1] = DWARF_LOC (sc_addr + LINUX_SC_R1_OFF, 0);
- c->dwarf.loc[UNW_ARM_R2] = DWARF_LOC (sc_addr + LINUX_SC_R2_OFF, 0);
- c->dwarf.loc[UNW_ARM_R3] = DWARF_LOC (sc_addr + LINUX_SC_R3_OFF, 0);
- c->dwarf.loc[UNW_ARM_R4] = DWARF_LOC (sc_addr + LINUX_SC_R4_OFF, 0);
- c->dwarf.loc[UNW_ARM_R5] = DWARF_LOC (sc_addr + LINUX_SC_R5_OFF, 0);
- c->dwarf.loc[UNW_ARM_R6] = DWARF_LOC (sc_addr + LINUX_SC_R6_OFF, 0);
- c->dwarf.loc[UNW_ARM_R7] = DWARF_LOC (sc_addr + LINUX_SC_R7_OFF, 0);
- c->dwarf.loc[UNW_ARM_R8] = DWARF_LOC (sc_addr + LINUX_SC_R8_OFF, 0);
- c->dwarf.loc[UNW_ARM_R9] = DWARF_LOC (sc_addr + LINUX_SC_R9_OFF, 0);
- c->dwarf.loc[UNW_ARM_R10] = DWARF_LOC (sc_addr + LINUX_SC_R10_OFF, 0);
- c->dwarf.loc[UNW_ARM_R11] = DWARF_LOC (sc_addr + LINUX_SC_FP_OFF, 0);
- c->dwarf.loc[UNW_ARM_R12] = DWARF_LOC (sc_addr + LINUX_SC_IP_OFF, 0);
- c->dwarf.loc[UNW_ARM_R13] = DWARF_LOC (sc_addr + LINUX_SC_SP_OFF, 0);
- c->dwarf.loc[UNW_ARM_R14] = DWARF_LOC (sc_addr + LINUX_SC_LR_OFF, 0);
- c->dwarf.loc[UNW_ARM_R15] = DWARF_LOC (sc_addr + LINUX_SC_PC_OFF, 0);
- /* Set SP/CFA and PC/IP. */
- dwarf_get (&c->dwarf, c->dwarf.loc[UNW_ARM_R13], &c->dwarf.cfa);
- dwarf_get (&c->dwarf, c->dwarf.loc[UNW_ARM_R15], &c->dwarf.ip);
- return 1;
- }
- PROTECTED int
- unw_step (unw_cursor_t *cursor)
- {
- struct cursor *c = (struct cursor *) cursor;
- int ret = -UNW_EUNSPEC;
- Debug (1, "(cursor=%p)\n", c);
- /* Check if this is a signal frame. */
- if (unw_is_signal_frame (cursor))
- return unw_handle_signal_frame (cursor);
- #ifdef CONFIG_DEBUG_FRAME
- /* First, try DWARF-based unwinding. */
- if (UNW_TRY_METHOD(UNW_ARM_METHOD_DWARF))
- {
- ret = dwarf_step (&c->dwarf);
- Debug(1, "dwarf_step()=%d\n", ret);
- if (likely (ret > 0))
- return 1;
- else if (unlikely (ret == -UNW_ESTOPUNWIND))
- return ret;
- if (ret < 0 && ret != -UNW_ENOINFO)
- {
- Debug (2, "returning %d\n", ret);
- return ret;
- }
- }
- #endif /* CONFIG_DEBUG_FRAME */
- /* Next, try extbl-based unwinding. */
- if (UNW_TRY_METHOD (UNW_ARM_METHOD_EXIDX))
- {
- ret = arm_exidx_step (c);
- if (ret > 0)
- return 1;
- if (ret == -UNW_ESTOPUNWIND || ret == 0)
- return ret;
- }
- /* Fall back on APCS frame parsing.
- Note: This won't work in case the ARM EABI is used. */
- if (unlikely (ret < 0))
- {
- if (UNW_TRY_METHOD(UNW_ARM_METHOD_FRAME))
- {
- ret = UNW_ESUCCESS;
- /* DWARF unwinding failed, try to follow APCS/optimized APCS frame chain */
- unw_word_t instr, i;
- Debug (13, "dwarf_step() failed (ret=%d), trying frame-chain\n", ret);
- dwarf_loc_t ip_loc, fp_loc;
- unw_word_t frame;
- /* Mark all registers unsaved, since we don't know where
- they are saved (if at all), except for the EBP and
- EIP. */
- if (dwarf_get(&c->dwarf, c->dwarf.loc[UNW_ARM_R11], &frame) < 0)
- {
- return 0;
- }
- for (i = 0; i < DWARF_NUM_PRESERVED_REGS; ++i) {
- c->dwarf.loc[i] = DWARF_NULL_LOC;
- }
- if (frame)
- {
- if (dwarf_get(&c->dwarf, DWARF_LOC(frame, 0), &instr) < 0)
- {
- return 0;
- }
- instr -= 8;
- if (dwarf_get(&c->dwarf, DWARF_LOC(instr, 0), &instr) < 0)
- {
- return 0;
- }
- if ((instr & 0xFFFFD800) == 0xE92DD800)
- {
- /* Standard APCS frame. */
- ip_loc = DWARF_LOC(frame - 4, 0);
- fp_loc = DWARF_LOC(frame - 12, 0);
- }
- else
- {
- /* Codesourcery optimized normal frame. */
- ip_loc = DWARF_LOC(frame, 0);
- fp_loc = DWARF_LOC(frame - 4, 0);
- }
- if (dwarf_get(&c->dwarf, ip_loc, &c->dwarf.ip) < 0)
- {
- return 0;
- }
- c->dwarf.loc[UNW_ARM_R12] = ip_loc;
- c->dwarf.loc[UNW_ARM_R11] = fp_loc;
- Debug(15, "ip=%lx\n", c->dwarf.ip);
- }
- else
- {
- ret = -UNW_ENOINFO;
- }
- }
- }
- return ret == -UNW_ENOINFO ? 0 : 1;
- }
|