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 <linux/sched/mm.h> 17 #include <linux/sched/debug.h> 18 19 #include <asm/arcregs.h> 20 #include <asm/irqflags.h> 21 22 /* 23 * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25) 24 * -Prints 3 regs per line and a CR. 25 * -To continue, callee regs right after scratch, special handling of CR 26 */ 27 static noinline void print_reg_file(long *reg_rev, int start_num) 28 { 29 unsigned int i; 30 char buf[512]; 31 int n = 0, len = sizeof(buf); 32 33 for (i = start_num; i < start_num + 13; i++) { 34 n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t", 35 i, (unsigned long)*reg_rev); 36 37 if (((i + 1) % 3) == 0) 38 n += scnprintf(buf + n, len - n, "\n"); 39 40 /* because pt_regs has regs reversed: r12..r0, r25..r13 */ 41 if (is_isa_arcv2() && start_num == 0) 42 reg_rev++; 43 else 44 reg_rev--; 45 } 46 47 if (start_num != 0) 48 n += scnprintf(buf + n, len - n, "\n\n"); 49 50 /* To continue printing callee regs on same line as scratch regs */ 51 if (start_num == 0) 52 pr_info("%s", buf); 53 else 54 pr_cont("%s\n", buf); 55 } 56 57 static void show_callee_regs(struct callee_regs *cregs) 58 { 59 print_reg_file(&(cregs->r13), 13); 60 } 61 62 static void print_task_path_n_nm(struct task_struct *tsk, char *buf) 63 { 64 char *path_nm = NULL; 65 struct mm_struct *mm; 66 struct file *exe_file; 67 68 mm = get_task_mm(tsk); 69 if (!mm) 70 goto done; 71 72 exe_file = get_mm_exe_file(mm); 73 mmput(mm); 74 75 if (exe_file) { 76 path_nm = file_path(exe_file, buf, 255); 77 fput(exe_file); 78 } 79 80 done: 81 pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?"); 82 } 83 84 static void show_faulting_vma(unsigned long address, char *buf) 85 { 86 struct vm_area_struct *vma; 87 struct inode *inode; 88 unsigned long ino = 0; 89 dev_t dev = 0; 90 char *nm = buf; 91 struct mm_struct *active_mm = current->active_mm; 92 93 /* can't use print_vma_addr() yet as it doesn't check for 94 * non-inclusive vma 95 */ 96 down_read(&active_mm->mmap_sem); 97 vma = find_vma(active_mm, address); 98 99 /* check against the find_vma( ) behaviour which returns the next VMA 100 * if the container VMA is not found 101 */ 102 if (vma && (vma->vm_start <= address)) { 103 struct file *file = vma->vm_file; 104 if (file) { 105 nm = file_path(file, buf, PAGE_SIZE - 1); 106 inode = file_inode(vma->vm_file); 107 dev = inode->i_sb->s_dev; 108 ino = inode->i_ino; 109 } 110 pr_info(" @off 0x%lx in [%s]\n" 111 " VMA: 0x%08lx to 0x%08lx\n", 112 vma->vm_start < TASK_UNMAPPED_BASE ? 113 address : address - vma->vm_start, 114 nm, vma->vm_start, vma->vm_end); 115 } else 116 pr_info(" @No matching VMA found\n"); 117 118 up_read(&active_mm->mmap_sem); 119 } 120 121 static void show_ecr_verbose(struct pt_regs *regs) 122 { 123 unsigned int vec, cause_code; 124 unsigned long address; 125 126 pr_info("\n[ECR ]: 0x%08lx => ", regs->event); 127 128 /* For Data fault, this is data address not instruction addr */ 129 address = current->thread.fault_address; 130 131 vec = regs->ecr_vec; 132 cause_code = regs->ecr_cause; 133 134 /* For DTLB Miss or ProtV, display the memory involved too */ 135 if (vec == ECR_V_DTLB_MISS) { 136 pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n", 137 (cause_code == 0x01) ? "Read" : 138 ((cause_code == 0x02) ? "Write" : "EX"), 139 address, regs->ret); 140 } else if (vec == ECR_V_ITLB_MISS) { 141 pr_cont("Insn could not be fetched\n"); 142 } else if (vec == ECR_V_MACH_CHK) { 143 pr_cont("Machine Check (%s)\n", (cause_code == 0x0) ? 144 "Double Fault" : "Other Fatal Err"); 145 146 } else if (vec == ECR_V_PROTV) { 147 if (cause_code == ECR_C_PROTV_INST_FETCH) 148 pr_cont("Execute from Non-exec Page\n"); 149 else if (cause_code == ECR_C_PROTV_MISALIG_DATA) 150 pr_cont("Misaligned r/w from 0x%08lx\n", address); 151 else 152 pr_cont("%s access not allowed on page\n", 153 (cause_code == 0x01) ? "Read" : 154 ((cause_code == 0x02) ? "Write" : "EX")); 155 } else if (vec == ECR_V_INSN_ERR) { 156 pr_cont("Illegal Insn\n"); 157 #ifdef CONFIG_ISA_ARCV2 158 } else if (vec == ECR_V_MEM_ERR) { 159 if (cause_code == 0x00) 160 pr_cont("Bus Error from Insn Mem\n"); 161 else if (cause_code == 0x10) 162 pr_cont("Bus Error from Data Mem\n"); 163 else 164 pr_cont("Bus Error, check PRM\n"); 165 #endif 166 } else if (vec == ECR_V_TRAP) { 167 if (regs->ecr_param == 5) 168 pr_cont("gcc generated __builtin_trap\n"); 169 } else { 170 pr_cont("Check Programmer's Manual\n"); 171 } 172 } 173 174 /************************************************************************ 175 * API called by rest of kernel 176 ***********************************************************************/ 177 178 void show_regs(struct pt_regs *regs) 179 { 180 struct task_struct *tsk = current; 181 struct callee_regs *cregs; 182 char *buf; 183 184 buf = (char *)__get_free_page(GFP_KERNEL); 185 if (!buf) 186 return; 187 188 print_task_path_n_nm(tsk, buf); 189 show_regs_print_info(KERN_INFO); 190 191 show_ecr_verbose(regs); 192 193 pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n", 194 current->thread.fault_address, 195 (void *)regs->blink, (void *)regs->ret); 196 197 if (user_mode(regs)) 198 show_faulting_vma(regs->ret, buf); /* faulting code, not data */ 199 200 pr_info("[STAT32]: 0x%08lx", regs->status32); 201 202 #define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit" " : "" 203 204 #ifdef CONFIG_ISA_ARCOMPACT 205 pr_cont(" : %2s%2s%2s%2s%2s%2s%2s\n", 206 (regs->status32 & STATUS_U_MASK) ? "U " : "K ", 207 STS_BIT(regs, DE), STS_BIT(regs, AE), 208 STS_BIT(regs, A2), STS_BIT(regs, A1), 209 STS_BIT(regs, E2), STS_BIT(regs, E1)); 210 #else 211 pr_cont(" : %2s%2s%2s%2s\n", 212 STS_BIT(regs, IE), 213 (regs->status32 & STATUS_U_MASK) ? "U " : "K ", 214 STS_BIT(regs, DE), STS_BIT(regs, AE)); 215 #endif 216 pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n", 217 regs->bta, regs->sp, regs->fp); 218 pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n", 219 regs->lp_start, regs->lp_end, regs->lp_count); 220 221 /* print regs->r0 thru regs->r12 222 * Sequential printing was generating horrible code 223 */ 224 print_reg_file(&(regs->r0), 0); 225 226 /* If Callee regs were saved, display them too */ 227 cregs = (struct callee_regs *)current->thread.callee_reg; 228 if (cregs) 229 show_callee_regs(cregs); 230 231 free_page((unsigned long)buf); 232 } 233 234 void show_kernel_fault_diag(const char *str, struct pt_regs *regs, 235 unsigned long address) 236 { 237 current->thread.fault_address = address; 238 239 /* Show fault description */ 240 pr_info("\n%s\n", str); 241 242 /* Caller and Callee regs */ 243 show_regs(regs); 244 245 /* Show stack trace if this Fatality happened in kernel mode */ 246 if (!user_mode(regs)) 247 show_stacktrace(current, regs); 248 } 249