kprobes: treewide: Cleanup the error messages for kprobes

+3 -1

arch/arm/probes/kprobes/core.c

··· 11 11 * Copyright (C) 2007 Marvell Ltd. 12 12 */ 13 13 14 + #define pr_fmt(fmt) "kprobes: " fmt 15 + 14 16 #include <linux/kernel.h> 15 17 #include <linux/kprobes.h> 16 18 #include <linux/module.h> ··· 280 278 break; 281 279 case KPROBE_REENTER: 282 280 /* A nested probe was hit in FIQ, it is a BUG */ 283 - pr_warn("Unrecoverable kprobe detected.\n"); 281 + pr_warn("Failed to recover from reentered kprobes.\n"); 284 282 dump_kprobe(p); 285 283 fallthrough; 286 284 default:

+4 -1

arch/arm64/kernel/probes/kprobes.c

··· 7 7 * Copyright (C) 2013 Linaro Limited. 8 8 * Author: Sandeepa Prabhu <sandeepa.prabhu@linaro.org> 9 9 */ 10 + 11 + #define pr_fmt(fmt) "kprobes: " fmt 12 + 10 13 #include <linux/extable.h> 11 14 #include <linux/kasan.h> 12 15 #include <linux/kernel.h> ··· 221 218 break; 222 219 case KPROBE_HIT_SS: 223 220 case KPROBE_REENTER: 224 - pr_warn("Unrecoverable kprobe detected.\n"); 221 + pr_warn("Failed to recover from reentered kprobes.\n"); 225 222 dump_kprobe(p); 226 223 BUG(); 227 224 break;

+5 -5

arch/csky/kernel/probes/kprobes.c

··· 1 1 // SPDX-License-Identifier: GPL-2.0+ 2 2 3 + #define pr_fmt(fmt) "kprobes: " fmt 4 + 3 5 #include <linux/kprobes.h> 4 6 #include <linux/extable.h> 5 7 #include <linux/slab.h> ··· 79 77 { 80 78 unsigned long probe_addr = (unsigned long)p->addr; 81 79 82 - if (probe_addr & 0x1) { 83 - pr_warn("Address not aligned.\n"); 84 - return -EINVAL; 85 - } 80 + if (probe_addr & 0x1) 81 + return -EILSEQ; 86 82 87 83 /* copy instruction */ 88 84 p->opcode = le32_to_cpu(*p->addr); ··· 225 225 break; 226 226 case KPROBE_HIT_SS: 227 227 case KPROBE_REENTER: 228 - pr_warn("Unrecoverable kprobe detected.\n"); 228 + pr_warn("Failed to recover from reentered kprobes.\n"); 229 229 dump_kprobe(p); 230 230 BUG(); 231 231 break;

+5 -6

arch/mips/kernel/kprobes.c

··· 11 11 * Copyright (C) IBM Corporation, 2002, 2004 12 12 */ 13 13 14 + #define pr_fmt(fmt) "kprobes: " fmt 15 + 14 16 #include <linux/kprobes.h> 15 17 #include <linux/preempt.h> 16 18 #include <linux/uaccess.h> ··· 82 80 insn = p->addr[0]; 83 81 84 82 if (insn_has_ll_or_sc(insn)) { 85 - pr_notice("Kprobes for ll and sc instructions are not" 86 - "supported\n"); 83 + pr_notice("Kprobes for ll and sc instructions are not supported\n"); 87 84 ret = -EINVAL; 88 85 goto out; 89 86 } ··· 220 219 return 0; 221 220 222 221 unaligned: 223 - pr_notice("%s: unaligned epc - sending SIGBUS.\n", current->comm); 222 + pr_notice("Failed to emulate branch instruction because of unaligned epc - sending SIGBUS to %s.\n", current->comm); 224 223 force_sig(SIGBUS); 225 224 return -EFAULT; 226 225 ··· 239 238 regs->cp0_epc = (unsigned long)p->addr; 240 239 else if (insn_has_delayslot(p->opcode)) { 241 240 ret = evaluate_branch_instruction(p, regs, kcb); 242 - if (ret < 0) { 243 - pr_notice("Kprobes: Error in evaluating branch\n"); 241 + if (ret < 0) 244 242 return; 245 - } 246 243 } 247 244 regs->cp0_epc = (unsigned long)&p->ainsn.insn[0]; 248 245 }

+5 -6

arch/riscv/kernel/probes/kprobes.c

··· 1 1 // SPDX-License-Identifier: GPL-2.0+ 2 2 3 + #define pr_fmt(fmt) "kprobes: " fmt 4 + 3 5 #include <linux/kprobes.h> 4 6 #include <linux/extable.h> 5 7 #include <linux/slab.h> ··· 52 50 { 53 51 unsigned long probe_addr = (unsigned long)p->addr; 54 52 55 - if (probe_addr & 0x1) { 56 - pr_warn("Address not aligned.\n"); 57 - 58 - return -EINVAL; 59 - } 53 + if (probe_addr & 0x1) 54 + return -EILSEQ; 60 55 61 56 /* copy instruction */ 62 57 p->opcode = *p->addr; ··· 190 191 break; 191 192 case KPROBE_HIT_SS: 192 193 case KPROBE_REENTER: 193 - pr_warn("Unrecoverable kprobe detected.\n"); 194 + pr_warn("Failed to recover from reentered kprobes.\n"); 194 195 dump_kprobe(p); 195 196 BUG(); 196 197 break;

+3 -1

arch/s390/kernel/kprobes.c

··· 7 7 * s390 port, used ppc64 as template. Mike Grundy <grundym@us.ibm.com> 8 8 */ 9 9 10 + #define pr_fmt(fmt) "kprobes: " fmt 11 + 10 12 #include <linux/moduleloader.h> 11 13 #include <linux/kprobes.h> 12 14 #include <linux/ptrace.h> ··· 261 259 * is a BUG. The code path resides in the .kprobes.text 262 260 * section and is executed with interrupts disabled. 263 261 */ 264 - pr_err("Invalid kprobe detected.\n"); 262 + pr_err("Failed to recover from reentered kprobes.\n"); 265 263 dump_kprobe(p); 266 264 BUG(); 267 265 }

+16 -20

kernel/kprobes.c

··· 18 18 * <jkenisto@us.ibm.com> and Prasanna S Panchamukhi 19 19 * <prasanna@in.ibm.com> added function-return probes. 20 20 */ 21 + 22 + #define pr_fmt(fmt) "kprobes: " fmt 23 + 21 24 #include <linux/kprobes.h> 22 25 #include <linux/hash.h> 23 26 #include <linux/init.h> ··· 895 892 optimize_kprobe(p); 896 893 } 897 894 cpus_read_unlock(); 898 - printk(KERN_INFO "Kprobes globally optimized\n"); 895 + pr_info("kprobe jump-optimization is enabled. All kprobes are optimized if possible.\n"); 899 896 out: 900 897 mutex_unlock(&kprobe_mutex); 901 898 } ··· 928 925 929 926 /* Wait for unoptimizing completion */ 930 927 wait_for_kprobe_optimizer(); 931 - printk(KERN_INFO "Kprobes globally unoptimized\n"); 928 + pr_info("kprobe jump-optimization is disabled. All kprobes are based on software breakpoint.\n"); 932 929 } 933 930 934 931 static DEFINE_MUTEX(kprobe_sysctl_mutex); ··· 1006 1003 * unregistered. 1007 1004 * Thus there should be no chance to reuse unused kprobe. 1008 1005 */ 1009 - printk(KERN_ERR "Error: There should be no unused kprobe here.\n"); 1006 + WARN_ON_ONCE(1); 1010 1007 return -EINVAL; 1011 1008 } 1012 1009 ··· 1043 1040 int ret = 0; 1044 1041 1045 1042 ret = ftrace_set_filter_ip(ops, (unsigned long)p->addr, 0, 0); 1046 - if (ret) { 1047 - pr_debug("Failed to arm kprobe-ftrace at %pS (%d)\n", 1048 - p->addr, ret); 1043 + if (WARN_ONCE(ret < 0, "Failed to arm kprobe-ftrace at %pS (error %d)\n", p->addr, ret)) 1049 1044 return ret; 1050 - } 1051 1045 1052 1046 if (*cnt == 0) { 1053 1047 ret = register_ftrace_function(ops); 1054 - if (ret) { 1055 - pr_debug("Failed to init kprobe-ftrace (%d)\n", ret); 1048 + if (WARN(ret < 0, "Failed to register kprobe-ftrace (error %d)\n", ret)) 1056 1049 goto err_ftrace; 1057 - } 1058 1050 } 1059 1051 1060 1052 (*cnt)++; ··· 1081 1083 1082 1084 if (*cnt == 1) { 1083 1085 ret = unregister_ftrace_function(ops); 1084 - if (WARN(ret < 0, "Failed to unregister kprobe-ftrace (%d)\n", ret)) 1086 + if (WARN(ret < 0, "Failed to unregister kprobe-ftrace (error %d)\n", ret)) 1085 1087 return ret; 1086 1088 } 1087 1089 1088 1090 (*cnt)--; 1089 1091 1090 1092 ret = ftrace_set_filter_ip(ops, (unsigned long)p->addr, 1, 0); 1091 - WARN_ONCE(ret < 0, "Failed to disarm kprobe-ftrace at %pS (%d)\n", 1093 + WARN_ONCE(ret < 0, "Failed to disarm kprobe-ftrace at %pS (error %d)\n", 1092 1094 p->addr, ret); 1093 1095 return ret; 1094 1096 } ··· 1878 1880 1879 1881 node = node->next; 1880 1882 } 1881 - pr_err("Oops! Kretprobe fails to find correct return address.\n"); 1883 + pr_err("kretprobe: Return address not found, not execute handler. Maybe there is a bug in the kernel.\n"); 1882 1884 BUG_ON(1); 1883 1885 1884 1886 found: ··· 2207 2209 /* Caller must NOT call this in usual path. This is only for critical case */ 2208 2210 void dump_kprobe(struct kprobe *kp) 2209 2211 { 2210 - pr_err("Dumping kprobe:\n"); 2211 - pr_err("Name: %s\nOffset: %x\nAddress: %pS\n", 2212 + pr_err("Dump kprobe:\n.symbol_name = %s, .offset = %x, .addr = %pS\n", 2212 2213 kp->symbol_name, kp->offset, kp->addr); 2213 2214 } 2214 2215 NOKPROBE_SYMBOL(dump_kprobe); ··· 2470 2473 err = populate_kprobe_blacklist(__start_kprobe_blacklist, 2471 2474 __stop_kprobe_blacklist); 2472 2475 if (err) { 2473 - pr_err("kprobes: failed to populate blacklist: %d\n", err); 2474 - pr_err("Please take care of using kprobes.\n"); 2476 + pr_err("Failed to populate blacklist (error %d), kprobes not restricted, be careful using them!\n", err); 2475 2477 } 2476 2478 2477 2479 if (kretprobe_blacklist_size) { ··· 2479 2483 kretprobe_blacklist[i].addr = 2480 2484 kprobe_lookup_name(kretprobe_blacklist[i].name, 0); 2481 2485 if (!kretprobe_blacklist[i].addr) 2482 - printk("kretprobe: lookup failed: %s\n", 2486 + pr_err("Failed to lookup symbol '%s' for kretprobe blacklist. Maybe the target function is removed or renamed.\n", 2483 2487 kretprobe_blacklist[i].name); 2484 2488 } 2485 2489 } ··· 2683 2687 } 2684 2688 2685 2689 if (errors) 2686 - pr_warn("Kprobes globally enabled, but failed to arm %d out of %d probes\n", 2690 + pr_warn("Kprobes globally enabled, but failed to enable %d out of %d probes. Please check which kprobes are kept disabled via debugfs.\n", 2687 2691 errors, total); 2688 2692 else 2689 2693 pr_info("Kprobes globally enabled\n"); ··· 2726 2730 } 2727 2731 2728 2732 if (errors) 2729 - pr_warn("Kprobes globally disabled, but failed to disarm %d out of %d probes\n", 2733 + pr_warn("Kprobes globally disabled, but failed to disable %d out of %d probes. Please check which kprobes are kept enabled via debugfs.\n", 2730 2734 errors, total); 2731 2735 else 2732 2736 pr_info("Kprobes globally disabled\n");

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