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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
21static 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
40static 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
54static 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
73done:
74 pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?");
75}
76
77static 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 = "anon";
94
95 if (vma->vm_file) {
96 /* XXX: can we use %pD below and get rid of buf? */
97 nm = d_path(file_user_path(vma->vm_file), buf,
98 ARC_PATH_MAX-1);
99 if (IS_ERR(nm))
100 nm = "?";
101 }
102 pr_info(" @off 0x%lx in [%s] VMA: 0x%08lx to 0x%08lx\n",
103 vma->vm_start < TASK_UNMAPPED_BASE ?
104 address : address - vma->vm_start,
105 nm, vma->vm_start, vma->vm_end);
106 } else
107 pr_info(" @No matching VMA found\n");
108
109 mmap_read_unlock(active_mm);
110}
111
112static void show_ecr_verbose(struct pt_regs *regs)
113{
114 unsigned int vec, cause_code;
115 unsigned long address;
116
117 /* For Data fault, this is data address not instruction addr */
118 address = current->thread.fault_address;
119
120 vec = regs->ecr.vec;
121 cause_code = regs->ecr.cause;
122
123 /* For DTLB Miss or ProtV, display the memory involved too */
124 if (vec == ECR_V_DTLB_MISS) {
125 pr_cont("Invalid %s @ 0x%08lx by insn @ %pS\n",
126 (cause_code == 0x01) ? "Read" :
127 ((cause_code == 0x02) ? "Write" : "EX"),
128 address, (void *)regs->ret);
129 } else if (vec == ECR_V_ITLB_MISS) {
130 pr_cont("Insn could not be fetched\n");
131 } else if (vec == ECR_V_MACH_CHK) {
132 pr_cont("Machine Check (%s)\n", (cause_code == 0x0) ?
133 "Double Fault" : "Other Fatal Err");
134
135 } else if (vec == ECR_V_PROTV) {
136 if (cause_code == ECR_C_PROTV_INST_FETCH)
137 pr_cont("Execute from Non-exec Page\n");
138 else if (cause_code == ECR_C_PROTV_MISALIG_DATA &&
139 IS_ENABLED(CONFIG_ISA_ARCOMPACT))
140 pr_cont("Misaligned r/w from 0x%08lx\n", address);
141 else
142 pr_cont("%s access not allowed on page\n",
143 (cause_code == 0x01) ? "Read" :
144 ((cause_code == 0x02) ? "Write" : "EX"));
145 } else if (vec == ECR_V_INSN_ERR) {
146 pr_cont("Illegal Insn\n");
147#ifdef CONFIG_ISA_ARCV2
148 } else if (vec == ECR_V_MEM_ERR) {
149 if (cause_code == 0x00)
150 pr_cont("Bus Error from Insn Mem\n");
151 else if (cause_code == 0x10)
152 pr_cont("Bus Error from Data Mem\n");
153 else
154 pr_cont("Bus Error, check PRM\n");
155 } else if (vec == ECR_V_MISALIGN) {
156 pr_cont("Misaligned r/w from 0x%08lx\n", address);
157#endif
158 } else if (vec == ECR_V_TRAP) {
159 if (regs->ecr.param == 5)
160 pr_cont("gcc generated __builtin_trap\n");
161 } else {
162 pr_cont("Check Programmer's Manual\n");
163 }
164}
165
166/************************************************************************
167 * API called by rest of kernel
168 ***********************************************************************/
169
170void show_regs(struct pt_regs *regs)
171{
172 struct task_struct *tsk = current;
173 struct callee_regs *cregs = (struct callee_regs *)tsk->thread.callee_reg;
174
175 /*
176 * generic code calls us with preemption disabled, but some calls
177 * here could sleep, so re-enable to avoid lockdep splat
178 */
179 preempt_enable();
180
181 print_task_path_n_nm(tsk);
182 show_regs_print_info(KERN_INFO);
183
184 show_ecr_verbose(regs);
185
186 if (user_mode(regs))
187 show_faulting_vma(regs->ret); /* faulting code, not data */
188
189 pr_info("ECR: 0x%08lx EFA: 0x%08lx ERET: 0x%08lx\n",
190 regs->ecr.full, current->thread.fault_address, regs->ret);
191
192 pr_info("STAT32: 0x%08lx", regs->status32);
193
194#define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit" " : ""
195
196#ifdef CONFIG_ISA_ARCOMPACT
197 pr_cont(" [%2s%2s%2s%2s%2s%2s%2s]",
198 (regs->status32 & STATUS_U_MASK) ? "U " : "K ",
199 STS_BIT(regs, DE), STS_BIT(regs, AE),
200 STS_BIT(regs, A2), STS_BIT(regs, A1),
201 STS_BIT(regs, E2), STS_BIT(regs, E1));
202#else
203 pr_cont(" [%2s%2s%2s%2s] ",
204 STS_BIT(regs, IE),
205 (regs->status32 & STATUS_U_MASK) ? "U " : "K ",
206 STS_BIT(regs, DE), STS_BIT(regs, AE));
207#endif
208
209 print_regs_scratch(regs);
210 if (cregs)
211 print_regs_callee(cregs);
212
213 preempt_disable();
214}
215
216void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
217 unsigned long address)
218{
219 current->thread.fault_address = address;
220
221 /* Show fault description */
222 pr_info("\n%s\n", str);
223
224 /* Caller and Callee regs */
225 show_regs(regs);
226
227 /* Show stack trace if this Fatality happened in kernel mode */
228 if (!user_mode(regs))
229 show_stacktrace(current, regs, KERN_DEFAULT);
230}
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
18/*
19 * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25)
20 * -Prints 3 regs per line and a CR.
21 * -To continue, callee regs right after scratch, special handling of CR
22 */
23static noinline void print_reg_file(long *reg_rev, int start_num)
24{
25 unsigned int i;
26 char buf[512];
27 int n = 0, len = sizeof(buf);
28
29 for (i = start_num; i < start_num + 13; i++) {
30 n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t",
31 i, (unsigned long)*reg_rev);
32
33 if (((i + 1) % 3) == 0)
34 n += scnprintf(buf + n, len - n, "\n");
35
36 /* because pt_regs has regs reversed: r12..r0, r25..r13 */
37 reg_rev--;
38 }
39
40 if (start_num != 0)
41 n += scnprintf(buf + n, len - n, "\n\n");
42
43 /* To continue printing callee regs on same line as scratch regs */
44 if (start_num == 0)
45 pr_info("%s", buf);
46 else
47 pr_cont("%s\n", buf);
48}
49
50static void show_callee_regs(struct callee_regs *cregs)
51{
52 print_reg_file(&(cregs->r13), 13);
53}
54
55void print_task_path_n_nm(struct task_struct *tsk, char *buf)
56{
57 struct path path;
58 char *path_nm = NULL;
59 struct mm_struct *mm;
60 struct file *exe_file;
61
62 mm = get_task_mm(tsk);
63 if (!mm)
64 goto done;
65
66 exe_file = get_mm_exe_file(mm);
67 mmput(mm);
68
69 if (exe_file) {
70 path = exe_file->f_path;
71 path_get(&exe_file->f_path);
72 fput(exe_file);
73 path_nm = d_path(&path, buf, 255);
74 path_put(&path);
75 }
76
77done:
78 pr_info("Path: %s\n", path_nm);
79}
80EXPORT_SYMBOL(print_task_path_n_nm);
81
82static void show_faulting_vma(unsigned long address, char *buf)
83{
84 struct vm_area_struct *vma;
85 struct inode *inode;
86 unsigned long ino = 0;
87 dev_t dev = 0;
88 char *nm = buf;
89
90 /* can't use print_vma_addr() yet as it doesn't check for
91 * non-inclusive vma
92 */
93
94 vma = find_vma(current->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 struct path *path = &file->f_path;
103 nm = d_path(path, buf, PAGE_SIZE - 1);
104 inode = file_inode(vma->vm_file);
105 dev = inode->i_sb->s_dev;
106 ino = inode->i_ino;
107 }
108 pr_info(" @off 0x%lx in [%s]\n"
109 " VMA: 0x%08lx to 0x%08lx\n",
110 vma->vm_start < TASK_UNMAPPED_BASE ?
111 address : address - vma->vm_start,
112 nm, vma->vm_start, vma->vm_end);
113 } else {
114 pr_info(" @No matching VMA found\n");
115 }
116}
117
118static 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 } else {
155 pr_cont("Check Programmer's Manual\n");
156 }
157}
158
159/************************************************************************
160 * API called by rest of kernel
161 ***********************************************************************/
162
163void show_regs(struct pt_regs *regs)
164{
165 struct task_struct *tsk = current;
166 struct callee_regs *cregs;
167 char *buf;
168
169 buf = (char *)__get_free_page(GFP_TEMPORARY);
170 if (!buf)
171 return;
172
173 print_task_path_n_nm(tsk, buf);
174 show_regs_print_info(KERN_INFO);
175
176 show_ecr_verbose(regs);
177
178 pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n",
179 current->thread.fault_address,
180 (void *)regs->blink, (void *)regs->ret);
181
182 if (user_mode(regs))
183 show_faulting_vma(regs->ret, buf); /* faulting code, not data */
184
185 pr_info("[STAT32]: 0x%08lx", regs->status32);
186
187#define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit : ""
188 if (!user_mode(regs))
189 pr_cont(" : %2s %2s %2s %2s %2s\n",
190 STS_BIT(regs, AE), STS_BIT(regs, A2), STS_BIT(regs, A1),
191 STS_BIT(regs, E2), STS_BIT(regs, E1));
192
193 pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n",
194 regs->bta, regs->sp, regs->fp);
195 pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
196 regs->lp_start, regs->lp_end, regs->lp_count);
197
198 /* print regs->r0 thru regs->r12
199 * Sequential printing was generating horrible code
200 */
201 print_reg_file(&(regs->r0), 0);
202
203 /* If Callee regs were saved, display them too */
204 cregs = (struct callee_regs *)current->thread.callee_reg;
205 if (cregs)
206 show_callee_regs(cregs);
207
208 free_page((unsigned long)buf);
209}
210
211void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
212 unsigned long address)
213{
214 current->thread.fault_address = address;
215
216 /* Caller and Callee regs */
217 show_regs(regs);
218
219 /* Show stack trace if this Fatality happened in kernel mode */
220 if (!user_mode(regs))
221 show_stacktrace(current, regs);
222}
223
224#ifdef CONFIG_DEBUG_FS
225
226#include <linux/module.h>
227#include <linux/fs.h>
228#include <linux/mount.h>
229#include <linux/pagemap.h>
230#include <linux/init.h>
231#include <linux/namei.h>
232#include <linux/debugfs.h>
233
234static struct dentry *test_dentry;
235static struct dentry *test_dir;
236static struct dentry *test_u32_dentry;
237
238static u32 clr_on_read = 1;
239
240#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
241u32 numitlb, numdtlb, num_pte_not_present;
242
243static int fill_display_data(char *kbuf)
244{
245 size_t num = 0;
246 num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb);
247 num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb);
248 num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present);
249
250 if (clr_on_read)
251 numitlb = numdtlb = num_pte_not_present = 0;
252
253 return num;
254}
255
256static int tlb_stats_open(struct inode *inode, struct file *file)
257{
258 file->private_data = (void *)__get_free_page(GFP_KERNEL);
259 return 0;
260}
261
262/* called on user read(): display the couters */
263static ssize_t tlb_stats_output(struct file *file, /* file descriptor */
264 char __user *user_buf, /* user buffer */
265 size_t len, /* length of buffer */
266 loff_t *offset) /* offset in the file */
267{
268 size_t num;
269 char *kbuf = (char *)file->private_data;
270
271 /* All of the data can he shoved in one iteration */
272 if (*offset != 0)
273 return 0;
274
275 num = fill_display_data(kbuf);
276
277 /* simple_read_from_buffer() is helper for copy to user space
278 It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
279 @3 (offset) into the user space address starting at @1 (user_buf).
280 @5 (len) is max size of user buffer
281 */
282 return simple_read_from_buffer(user_buf, num, offset, kbuf, len);
283}
284
285/* called on user write : clears the counters */
286static ssize_t tlb_stats_clear(struct file *file, const char __user *user_buf,
287 size_t length, loff_t *offset)
288{
289 numitlb = numdtlb = num_pte_not_present = 0;
290 return length;
291}
292
293static int tlb_stats_close(struct inode *inode, struct file *file)
294{
295 free_page((unsigned long)(file->private_data));
296 return 0;
297}
298
299static const struct file_operations tlb_stats_file_ops = {
300 .read = tlb_stats_output,
301 .write = tlb_stats_clear,
302 .open = tlb_stats_open,
303 .release = tlb_stats_close
304};
305#endif
306
307static int __init arc_debugfs_init(void)
308{
309 test_dir = debugfs_create_dir("arc", NULL);
310
311#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
312 test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL,
313 &tlb_stats_file_ops);
314#endif
315
316 test_u32_dentry =
317 debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read);
318
319 return 0;
320}
321
322module_init(arc_debugfs_init);
323
324static void __exit arc_debugfs_exit(void)
325{
326 debugfs_remove(test_u32_dentry);
327 debugfs_remove(test_dentry);
328 debugfs_remove(test_dir);
329}
330module_exit(arc_debugfs_exit);
331
332#endif