1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 */
5
6 #include <linux/ptrace.h>
7 #include <linux/module.h>
8 #include <linux/mm.h>
9 #include <linux/fs.h>
10 #include <linux/kdev_t.h>
11 #include <linux/proc_fs.h>
12 #include <linux/file.h>
13 #include <linux/sched/mm.h>
14 #include <linux/sched/debug.h>
15
16 #include <asm/arcregs.h>
17 #include <asm/irqflags.h>
18
19 #define ARC_PATH_MAX 256
20
print_regs_scratch(struct pt_regs * regs)21 static noinline void print_regs_scratch(struct pt_regs *regs)
22 {
23 pr_cont("BTA: 0x%08lx\n SP: 0x%08lx FP: 0x%08lx BLK: %pS\n",
24 regs->bta, regs->sp, regs->fp, (void *)regs->blink);
25 pr_cont("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
26 regs->lp_start, regs->lp_end, regs->lp_count);
27
28 pr_info("r00: 0x%08lx\tr01: 0x%08lx\tr02: 0x%08lx\n" \
29 "r03: 0x%08lx\tr04: 0x%08lx\tr05: 0x%08lx\n" \
30 "r06: 0x%08lx\tr07: 0x%08lx\tr08: 0x%08lx\n" \
31 "r09: 0x%08lx\tr10: 0x%08lx\tr11: 0x%08lx\n" \
32 "r12: 0x%08lx\t",
33 regs->r0, regs->r1, regs->r2,
34 regs->r3, regs->r4, regs->r5,
35 regs->r6, regs->r7, regs->r8,
36 regs->r9, regs->r10, regs->r11,
37 regs->r12);
38 }
39
print_regs_callee(struct callee_regs * regs)40 static void print_regs_callee(struct callee_regs *regs)
41 {
42 pr_cont("r13: 0x%08lx\tr14: 0x%08lx\n" \
43 "r15: 0x%08lx\tr16: 0x%08lx\tr17: 0x%08lx\n" \
44 "r18: 0x%08lx\tr19: 0x%08lx\tr20: 0x%08lx\n" \
45 "r21: 0x%08lx\tr22: 0x%08lx\tr23: 0x%08lx\n" \
46 "r24: 0x%08lx\tr25: 0x%08lx\n",
47 regs->r13, regs->r14,
48 regs->r15, regs->r16, regs->r17,
49 regs->r18, regs->r19, regs->r20,
50 regs->r21, regs->r22, regs->r23,
51 regs->r24, regs->r25);
52 }
53
print_task_path_n_nm(struct task_struct * tsk)54 static void print_task_path_n_nm(struct task_struct *tsk)
55 {
56 char *path_nm = NULL;
57 struct mm_struct *mm;
58 struct file *exe_file;
59 char buf[ARC_PATH_MAX];
60
61 mm = get_task_mm(tsk);
62 if (!mm)
63 goto done;
64
65 exe_file = get_mm_exe_file(mm);
66 mmput(mm);
67
68 if (exe_file) {
69 path_nm = file_path(exe_file, buf, ARC_PATH_MAX-1);
70 fput(exe_file);
71 }
72
73 done:
74 pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?");
75 }
76
show_faulting_vma(unsigned long address)77 static void show_faulting_vma(unsigned long address)
78 {
79 struct vm_area_struct *vma;
80 struct mm_struct *active_mm = current->active_mm;
81
82 /* can't use print_vma_addr() yet as it doesn't check for
83 * non-inclusive vma
84 */
85 mmap_read_lock(active_mm);
86 vma = vma_lookup(active_mm, address);
87
88 /* Lookup the vma at the address and report if the container VMA is not
89 * found
90 */
91 if (vma) {
92 char buf[ARC_PATH_MAX];
93 char *nm = "?";
94
95 if (vma->vm_file) {
96 nm = file_path(vma->vm_file, buf, ARC_PATH_MAX-1);
97 if (IS_ERR(nm))
98 nm = "?";
99 }
100 pr_info(" @off 0x%lx in [%s] VMA: 0x%08lx to 0x%08lx\n",
101 vma->vm_start < TASK_UNMAPPED_BASE ?
102 address : address - vma->vm_start,
103 nm, vma->vm_start, vma->vm_end);
104 } else
105 pr_info(" @No matching VMA found\n");
106
107 mmap_read_unlock(active_mm);
108 }
109
show_ecr_verbose(struct pt_regs * regs)110 static void show_ecr_verbose(struct pt_regs *regs)
111 {
112 unsigned int vec, cause_code;
113 unsigned long address;
114
115 /* For Data fault, this is data address not instruction addr */
116 address = current->thread.fault_address;
117
118 vec = regs->ecr.vec;
119 cause_code = regs->ecr.cause;
120
121 /* For DTLB Miss or ProtV, display the memory involved too */
122 if (vec == ECR_V_DTLB_MISS) {
123 pr_cont("Invalid %s @ 0x%08lx by insn @ %pS\n",
124 (cause_code == 0x01) ? "Read" :
125 ((cause_code == 0x02) ? "Write" : "EX"),
126 address, (void *)regs->ret);
127 } else if (vec == ECR_V_ITLB_MISS) {
128 pr_cont("Insn could not be fetched\n");
129 } else if (vec == ECR_V_MACH_CHK) {
130 pr_cont("Machine Check (%s)\n", (cause_code == 0x0) ?
131 "Double Fault" : "Other Fatal Err");
132
133 } else if (vec == ECR_V_PROTV) {
134 if (cause_code == ECR_C_PROTV_INST_FETCH)
135 pr_cont("Execute from Non-exec Page\n");
136 else if (cause_code == ECR_C_PROTV_MISALIG_DATA &&
137 IS_ENABLED(CONFIG_ISA_ARCOMPACT))
138 pr_cont("Misaligned r/w from 0x%08lx\n", address);
139 else
140 pr_cont("%s access not allowed on page\n",
141 (cause_code == 0x01) ? "Read" :
142 ((cause_code == 0x02) ? "Write" : "EX"));
143 } else if (vec == ECR_V_INSN_ERR) {
144 pr_cont("Illegal Insn\n");
145 #ifdef CONFIG_ISA_ARCV2
146 } else if (vec == ECR_V_MEM_ERR) {
147 if (cause_code == 0x00)
148 pr_cont("Bus Error from Insn Mem\n");
149 else if (cause_code == 0x10)
150 pr_cont("Bus Error from Data Mem\n");
151 else
152 pr_cont("Bus Error, check PRM\n");
153 } else if (vec == ECR_V_MISALIGN) {
154 pr_cont("Misaligned r/w from 0x%08lx\n", address);
155 #endif
156 } else if (vec == ECR_V_TRAP) {
157 if (regs->ecr.param == 5)
158 pr_cont("gcc generated __builtin_trap\n");
159 } else {
160 pr_cont("Check Programmer's Manual\n");
161 }
162 }
163
164 /************************************************************************
165 * API called by rest of kernel
166 ***********************************************************************/
167
show_regs(struct pt_regs * regs)168 void show_regs(struct pt_regs *regs)
169 {
170 struct task_struct *tsk = current;
171 struct callee_regs *cregs = (struct callee_regs *)tsk->thread.callee_reg;
172
173 /*
174 * generic code calls us with preemption disabled, but some calls
175 * here could sleep, so re-enable to avoid lockdep splat
176 */
177 preempt_enable();
178
179 print_task_path_n_nm(tsk);
180 show_regs_print_info(KERN_INFO);
181
182 show_ecr_verbose(regs);
183
184 if (user_mode(regs))
185 show_faulting_vma(regs->ret); /* faulting code, not data */
186
187 pr_info("ECR: 0x%08lx EFA: 0x%08lx ERET: 0x%08lx\n",
188 regs->ecr.full, current->thread.fault_address, regs->ret);
189
190 pr_info("STAT32: 0x%08lx", regs->status32);
191
192 #define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit" " : ""
193
194 #ifdef CONFIG_ISA_ARCOMPACT
195 pr_cont(" [%2s%2s%2s%2s%2s%2s%2s]",
196 (regs->status32 & STATUS_U_MASK) ? "U " : "K ",
197 STS_BIT(regs, DE), STS_BIT(regs, AE),
198 STS_BIT(regs, A2), STS_BIT(regs, A1),
199 STS_BIT(regs, E2), STS_BIT(regs, E1));
200 #else
201 pr_cont(" [%2s%2s%2s%2s] ",
202 STS_BIT(regs, IE),
203 (regs->status32 & STATUS_U_MASK) ? "U " : "K ",
204 STS_BIT(regs, DE), STS_BIT(regs, AE));
205 #endif
206
207 print_regs_scratch(regs);
208 if (cregs)
209 print_regs_callee(cregs);
210
211 preempt_disable();
212 }
213
show_kernel_fault_diag(const char * str,struct pt_regs * regs,unsigned long address)214 void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
215 unsigned long address)
216 {
217 current->thread.fault_address = address;
218
219 /* Show fault description */
220 pr_info("\n%s\n", str);
221
222 /* Caller and Callee regs */
223 show_regs(regs);
224
225 /* Show stack trace if this Fatality happened in kernel mode */
226 if (!user_mode(regs))
227 show_stacktrace(current, regs, KERN_DEFAULT);
228 }
229