1 /* 2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 */ 7 8 #include <linux/ptrace.h> 9 #include <linux/module.h> 10 #include <linux/mm.h> 11 #include <linux/fs.h> 12 #include <linux/kdev_t.h> 13 #include <linux/fs_struct.h> 14 #include <linux/proc_fs.h> 15 #include <linux/file.h> 16 #include <asm/arcregs.h> 17 #include <asm/irqflags.h> 18 19 /* 20 * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25) 21 * -Prints 3 regs per line and a CR. 22 * -To continue, callee regs right after scratch, special handling of CR 23 */ 24 static noinline void print_reg_file(long *reg_rev, int start_num) 25 { 26 unsigned int i; 27 char buf[512]; 28 int n = 0, len = sizeof(buf); 29 30 for (i = start_num; i < start_num + 13; i++) { 31 n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t", 32 i, (unsigned long)*reg_rev); 33 34 if (((i + 1) % 3) == 0) 35 n += scnprintf(buf + n, len - n, "\n"); 36 37 /* because pt_regs has regs reversed: r12..r0, r25..r13 */ 38 if (is_isa_arcv2() && start_num == 0) 39 reg_rev++; 40 else 41 reg_rev--; 42 } 43 44 if (start_num != 0) 45 n += scnprintf(buf + n, len - n, "\n\n"); 46 47 /* To continue printing callee regs on same line as scratch regs */ 48 if (start_num == 0) 49 pr_info("%s", buf); 50 else 51 pr_cont("%s\n", buf); 52 } 53 54 static void show_callee_regs(struct callee_regs *cregs) 55 { 56 print_reg_file(&(cregs->r13), 13); 57 } 58 59 static void print_task_path_n_nm(struct task_struct *tsk, char *buf) 60 { 61 char *path_nm = NULL; 62 struct mm_struct *mm; 63 struct file *exe_file; 64 65 mm = get_task_mm(tsk); 66 if (!mm) 67 goto done; 68 69 exe_file = get_mm_exe_file(mm); 70 mmput(mm); 71 72 if (exe_file) { 73 path_nm = file_path(exe_file, buf, 255); 74 fput(exe_file); 75 } 76 77 done: 78 pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?"); 79 } 80 81 static void show_faulting_vma(unsigned long address, char *buf) 82 { 83 struct vm_area_struct *vma; 84 struct inode *inode; 85 unsigned long ino = 0; 86 dev_t dev = 0; 87 char *nm = buf; 88 struct mm_struct *active_mm = current->active_mm; 89 90 /* can't use print_vma_addr() yet as it doesn't check for 91 * non-inclusive vma 92 */ 93 down_read(&active_mm->mmap_sem); 94 vma = find_vma(active_mm, address); 95 96 /* check against the find_vma( ) behaviour which returns the next VMA 97 * if the container VMA is not found 98 */ 99 if (vma && (vma->vm_start <= address)) { 100 struct file *file = vma->vm_file; 101 if (file) { 102 nm = file_path(file, buf, PAGE_SIZE - 1); 103 inode = file_inode(vma->vm_file); 104 dev = inode->i_sb->s_dev; 105 ino = inode->i_ino; 106 } 107 pr_info(" @off 0x%lx in [%s]\n" 108 " VMA: 0x%08lx to 0x%08lx\n", 109 vma->vm_start < TASK_UNMAPPED_BASE ? 110 address : address - vma->vm_start, 111 nm, vma->vm_start, vma->vm_end); 112 } else 113 pr_info(" @No matching VMA found\n"); 114 115 up_read(&active_mm->mmap_sem); 116 } 117 118 static void show_ecr_verbose(struct pt_regs *regs) 119 { 120 unsigned int vec, cause_code; 121 unsigned long address; 122 123 pr_info("\n[ECR ]: 0x%08lx => ", regs->event); 124 125 /* For Data fault, this is data address not instruction addr */ 126 address = current->thread.fault_address; 127 128 vec = regs->ecr_vec; 129 cause_code = regs->ecr_cause; 130 131 /* For DTLB Miss or ProtV, display the memory involved too */ 132 if (vec == ECR_V_DTLB_MISS) { 133 pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n", 134 (cause_code == 0x01) ? "Read" : 135 ((cause_code == 0x02) ? "Write" : "EX"), 136 address, regs->ret); 137 } else if (vec == ECR_V_ITLB_MISS) { 138 pr_cont("Insn could not be fetched\n"); 139 } else if (vec == ECR_V_MACH_CHK) { 140 pr_cont("%s\n", (cause_code == 0x0) ? 141 "Double Fault" : "Other Fatal Err"); 142 143 } else if (vec == ECR_V_PROTV) { 144 if (cause_code == ECR_C_PROTV_INST_FETCH) 145 pr_cont("Execute from Non-exec Page\n"); 146 else if (cause_code == ECR_C_PROTV_MISALIG_DATA) 147 pr_cont("Misaligned r/w from 0x%08lx\n", address); 148 else 149 pr_cont("%s access not allowed on page\n", 150 (cause_code == 0x01) ? "Read" : 151 ((cause_code == 0x02) ? "Write" : "EX")); 152 } else if (vec == ECR_V_INSN_ERR) { 153 pr_cont("Illegal Insn\n"); 154 #ifdef CONFIG_ISA_ARCV2 155 } else if (vec == ECR_V_MEM_ERR) { 156 if (cause_code == 0x00) 157 pr_cont("Bus Error from Insn Mem\n"); 158 else if (cause_code == 0x10) 159 pr_cont("Bus Error from Data Mem\n"); 160 else 161 pr_cont("Bus Error, check PRM\n"); 162 #endif 163 } else { 164 pr_cont("Check Programmer's Manual\n"); 165 } 166 } 167 168 /************************************************************************ 169 * API called by rest of kernel 170 ***********************************************************************/ 171 172 void show_regs(struct pt_regs *regs) 173 { 174 struct task_struct *tsk = current; 175 struct callee_regs *cregs; 176 char *buf; 177 178 buf = (char *)__get_free_page(GFP_TEMPORARY); 179 if (!buf) 180 return; 181 182 print_task_path_n_nm(tsk, buf); 183 show_regs_print_info(KERN_INFO); 184 185 show_ecr_verbose(regs); 186 187 pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n", 188 current->thread.fault_address, 189 (void *)regs->blink, (void *)regs->ret); 190 191 if (user_mode(regs)) 192 show_faulting_vma(regs->ret, buf); /* faulting code, not data */ 193 194 pr_info("[STAT32]: 0x%08lx", regs->status32); 195 196 #define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit" " : "" 197 198 #ifdef CONFIG_ISA_ARCOMPACT 199 pr_cont(" : %2s%2s%2s%2s%2s%2s%2s\n", 200 (regs->status32 & STATUS_U_MASK) ? "U " : "K ", 201 STS_BIT(regs, DE), STS_BIT(regs, AE), 202 STS_BIT(regs, A2), STS_BIT(regs, A1), 203 STS_BIT(regs, E2), STS_BIT(regs, E1)); 204 #else 205 pr_cont(" : %2s%2s%2s%2s\n", 206 STS_BIT(regs, IE), 207 (regs->status32 & STATUS_U_MASK) ? "U " : "K ", 208 STS_BIT(regs, DE), STS_BIT(regs, AE)); 209 #endif 210 pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n", 211 regs->bta, regs->sp, regs->fp); 212 pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n", 213 regs->lp_start, regs->lp_end, regs->lp_count); 214 215 /* print regs->r0 thru regs->r12 216 * Sequential printing was generating horrible code 217 */ 218 print_reg_file(&(regs->r0), 0); 219 220 /* If Callee regs were saved, display them too */ 221 cregs = (struct callee_regs *)current->thread.callee_reg; 222 if (cregs) 223 show_callee_regs(cregs); 224 225 free_page((unsigned long)buf); 226 } 227 228 void show_kernel_fault_diag(const char *str, struct pt_regs *regs, 229 unsigned long address) 230 { 231 current->thread.fault_address = address; 232 233 /* Caller and Callee regs */ 234 show_regs(regs); 235 236 /* Show stack trace if this Fatality happened in kernel mode */ 237 if (!user_mode(regs)) 238 show_stacktrace(current, regs); 239 } 240