1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/kernel.h> 3 #include <linux/stdarg.h> 4 #include <linux/string.h> 5 #include <linux/ctype.h> 6 #include <asm/stacktrace.h> 7 #include <asm/boot_data.h> 8 #include <asm/lowcore.h> 9 #include <asm/setup.h> 10 #include <asm/sclp.h> 11 #include <asm/uv.h> 12 #include "boot.h" 13 14 const char hex_asc[] = "0123456789abcdef"; 15 16 static char *as_hex(char *dst, unsigned long val, int pad) 17 { 18 char *p, *end = p = dst + max(pad, (int)__fls(val | 1) / 4 + 1); 19 20 for (*p-- = 0; p >= dst; val >>= 4) 21 *p-- = hex_asc[val & 0x0f]; 22 return end; 23 } 24 25 static char *symstart(char *p) 26 { 27 while (*p) 28 p--; 29 return p + 1; 30 } 31 32 static noinline char *findsym(unsigned long ip, unsigned short *off, unsigned short *len) 33 { 34 /* symbol entries are in a form "10000 c4 startup\0" */ 35 char *a = _decompressor_syms_start; 36 char *b = _decompressor_syms_end; 37 unsigned long start; 38 unsigned long size; 39 char *pivot; 40 char *endp; 41 42 while (a < b) { 43 pivot = symstart(a + (b - a) / 2); 44 start = simple_strtoull(pivot, &endp, 16); 45 size = simple_strtoull(endp + 1, &endp, 16); 46 if (ip < start) { 47 b = pivot; 48 continue; 49 } 50 if (ip > start + size) { 51 a = pivot + strlen(pivot) + 1; 52 continue; 53 } 54 *off = ip - start; 55 *len = size; 56 return endp + 1; 57 } 58 return NULL; 59 } 60 61 static noinline char *strsym(void *ip) 62 { 63 static char buf[64]; 64 unsigned short off; 65 unsigned short len; 66 char *p; 67 68 p = findsym((unsigned long)ip, &off, &len); 69 if (p) { 70 strncpy(buf, p, sizeof(buf)); 71 /* reserve 15 bytes for offset/len in symbol+0x1234/0x1234 */ 72 p = buf + strnlen(buf, sizeof(buf) - 15); 73 strcpy(p, "+0x"); 74 p = as_hex(p + 3, off, 0); 75 strcpy(p, "/0x"); 76 as_hex(p + 3, len, 0); 77 } else { 78 as_hex(buf, (unsigned long)ip, 16); 79 } 80 return buf; 81 } 82 83 void decompressor_printk(const char *fmt, ...) 84 { 85 char buf[1024] = { 0 }; 86 char *end = buf + sizeof(buf) - 1; /* make sure buf is 0 terminated */ 87 unsigned long pad; 88 char *p = buf; 89 va_list args; 90 91 va_start(args, fmt); 92 for (; p < end && *fmt; fmt++) { 93 if (*fmt != '%') { 94 *p++ = *fmt; 95 continue; 96 } 97 pad = isdigit(*++fmt) ? simple_strtol(fmt, (char **)&fmt, 10) : 0; 98 switch (*fmt) { 99 case 's': 100 p = buf + strlcat(buf, va_arg(args, char *), sizeof(buf)); 101 break; 102 case 'p': 103 if (*++fmt != 'S') 104 goto out; 105 p = buf + strlcat(buf, strsym(va_arg(args, void *)), sizeof(buf)); 106 break; 107 case 'l': 108 if (*++fmt != 'x' || end - p <= max(sizeof(long) * 2, pad)) 109 goto out; 110 p = as_hex(p, va_arg(args, unsigned long), pad); 111 break; 112 case 'x': 113 if (end - p <= max(sizeof(int) * 2, pad)) 114 goto out; 115 p = as_hex(p, va_arg(args, unsigned int), pad); 116 break; 117 default: 118 goto out; 119 } 120 } 121 out: 122 va_end(args); 123 sclp_early_printk(buf); 124 } 125 126 static noinline void print_stacktrace(void) 127 { 128 struct stack_info boot_stack = { STACK_TYPE_TASK, (unsigned long)_stack_start, 129 (unsigned long)_stack_end }; 130 unsigned long sp = S390_lowcore.gpregs_save_area[15]; 131 bool first = true; 132 133 decompressor_printk("Call Trace:\n"); 134 while (!(sp & 0x7) && on_stack(&boot_stack, sp, sizeof(struct stack_frame))) { 135 struct stack_frame *sf = (struct stack_frame *)sp; 136 137 decompressor_printk(first ? "(sp:%016lx [<%016lx>] %pS)\n" : 138 " sp:%016lx [<%016lx>] %pS\n", 139 sp, sf->gprs[8], (void *)sf->gprs[8]); 140 if (sf->back_chain <= sp) 141 break; 142 sp = sf->back_chain; 143 first = false; 144 } 145 } 146 147 void print_pgm_check_info(void) 148 { 149 unsigned long *gpregs = (unsigned long *)S390_lowcore.gpregs_save_area; 150 struct psw_bits *psw = &psw_bits(S390_lowcore.psw_save_area); 151 152 decompressor_printk("Linux version %s\n", kernel_version); 153 if (!is_prot_virt_guest() && early_command_line[0]) 154 decompressor_printk("Kernel command line: %s\n", early_command_line); 155 decompressor_printk("Kernel fault: interruption code %04x ilc:%x\n", 156 S390_lowcore.pgm_code, S390_lowcore.pgm_ilc >> 1); 157 if (kaslr_enabled) 158 decompressor_printk("Kernel random base: %lx\n", __kaslr_offset); 159 decompressor_printk("PSW : %016lx %016lx (%pS)\n", 160 S390_lowcore.psw_save_area.mask, 161 S390_lowcore.psw_save_area.addr, 162 (void *)S390_lowcore.psw_save_area.addr); 163 decompressor_printk( 164 " R:%x T:%x IO:%x EX:%x Key:%x M:%x W:%x P:%x AS:%x CC:%x PM:%x RI:%x EA:%x\n", 165 psw->per, psw->dat, psw->io, psw->ext, psw->key, psw->mcheck, 166 psw->wait, psw->pstate, psw->as, psw->cc, psw->pm, psw->ri, 167 psw->eaba); 168 decompressor_printk("GPRS: %016lx %016lx %016lx %016lx\n", 169 gpregs[0], gpregs[1], gpregs[2], gpregs[3]); 170 decompressor_printk(" %016lx %016lx %016lx %016lx\n", 171 gpregs[4], gpregs[5], gpregs[6], gpregs[7]); 172 decompressor_printk(" %016lx %016lx %016lx %016lx\n", 173 gpregs[8], gpregs[9], gpregs[10], gpregs[11]); 174 decompressor_printk(" %016lx %016lx %016lx %016lx\n", 175 gpregs[12], gpregs[13], gpregs[14], gpregs[15]); 176 print_stacktrace(); 177 decompressor_printk("Last Breaking-Event-Address:\n"); 178 decompressor_printk(" [<%016lx>] %pS\n", (unsigned long)S390_lowcore.breaking_event_addr, 179 (void *)S390_lowcore.breaking_event_addr); 180 } 181