1 /*- 2 * Copyright (c) 2005 Antoine Brodin 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/systm.h> 31 #include <sys/param.h> 32 #include <sys/proc.h> 33 #include <sys/stack.h> 34 35 #include <machine/vmparam.h> 36 #include <machine/pcb.h> 37 #include <machine/stack.h> 38 39 /* 40 * This code makes assumptions about the stack layout. These are correct 41 * when using APCS (the old ABI), but are no longer true with AAPCS and the 42 * ARM EABI. There is also an issue with clang and llvm when building for 43 * APCS where it lays out the stack incorrectly. Because of this we disable 44 * this when building for ARM EABI or when building with clang. 45 */ 46 static void 47 stack_capture(struct stack *st, u_int32_t *frame) 48 { 49 #if !defined(__ARM_EABI__) && !defined(__clang__) 50 vm_offset_t callpc; 51 52 while (INKERNEL(frame)) { 53 callpc = frame[FR_SCP]; 54 if (stack_put(st, callpc) == -1) 55 break; 56 frame = (u_int32_t *)(frame[FR_RFP]); 57 } 58 #endif 59 } 60 61 void 62 stack_save_td(struct stack *st, struct thread *td) 63 { 64 u_int32_t *frame; 65 66 if (TD_IS_SWAPPED(td)) 67 panic("stack_save_td: swapped"); 68 if (TD_IS_RUNNING(td)) 69 panic("stack_save_td: running"); 70 71 /* 72 * This register, the frame pointer, is incorrect for the ARM EABI 73 * as it doesn't have a frame pointer, however it's value is not used 74 * when building for EABI. 75 */ 76 frame = (u_int32_t *)td->td_pcb->un_32.pcb32_r11; 77 stack_zero(st); 78 stack_capture(st, frame); 79 } 80 81 void 82 stack_save(struct stack *st) 83 { 84 u_int32_t *frame; 85 86 frame = (u_int32_t *)__builtin_frame_address(0); 87 stack_zero(st); 88 stack_capture(st, frame); 89 } 90