1#!/usr/bin/gawk -f 2# SPDX-License-Identifier: GPL-2.0 3# verify_builtin_ranges.awk: Verify address range data for builtin modules 4# Written by Kris Van Hees <kris.van.hees@oracle.com> 5# 6# Usage: verify_builtin_ranges.awk modules.builtin.ranges System.map \ 7# modules.builtin vmlinux.map vmlinux.o.map 8# 9 10# Return the module name(s) (if any) associated with the given object. 11# 12# If we have seen this object before, return information from the cache. 13# Otherwise, retrieve it from the corresponding .cmd file. 14# 15function get_module_info(fn, mod, obj, s) { 16 if (fn in omod) 17 return omod[fn]; 18 19 if (match(fn, /\/[^/]+$/) == 0) 20 return ""; 21 22 obj = fn; 23 mod = ""; 24 fn = substr(fn, 1, RSTART) "." substr(fn, RSTART + 1) ".cmd"; 25 if (getline s <fn == 1) { 26 if (match(s, /DKBUILD_MODFILE=['"]+[^'"]+/) > 0) { 27 mod = substr(s, RSTART + 16, RLENGTH - 16); 28 gsub(/['"]/, "", mod); 29 } else if (match(s, /RUST_MODFILE=[^ ]+/) > 0) 30 mod = substr(s, RSTART + 13, RLENGTH - 13); 31 } else { 32 print "ERROR: Failed to read: " fn "\n\n" \ 33 " For kernels built with O=<objdir>, cd to <objdir>\n" \ 34 " and execute this script as ./source/scripts/..." \ 35 >"/dev/stderr"; 36 close(fn); 37 total = 0; 38 exit(1); 39 } 40 close(fn); 41 42 # A single module (common case) also reflects objects that are not part 43 # of a module. Some of those objects have names that are also a module 44 # name (e.g. core). We check the associated module file name, and if 45 # they do not match, the object is not part of a module. 46 if (mod !~ / /) { 47 if (!(mod in mods)) 48 mod = ""; 49 } 50 51 gsub(/([^/ ]*\/)+/, "", mod); 52 gsub(/-/, "_", mod); 53 54 # At this point, mod is a single (valid) module name, or a list of 55 # module names (that do not need validation). 56 omod[obj] = mod; 57 58 return mod; 59} 60 61# Return a representative integer value for a given hexadecimal address. 62# 63# Since all kernel addresses fall within the same memory region, we can safely 64# strip off the first 6 hex digits before performing the hex-to-dec conversion, 65# thereby avoiding integer overflows. 66# 67function addr2val(val) { 68 sub(/^0x/, "", val); 69 if (length(val) == 16) 70 val = substr(val, 5); 71 return strtonum("0x" val); 72} 73 74# Determine the kernel build directory to use (default is .). 75# 76BEGIN { 77 if (ARGC < 6) { 78 print "Syntax: verify_builtin_ranges.awk <ranges-file> <system-map>\n" \ 79 " <builtin-file> <vmlinux-map> <vmlinux-o-map>\n" \ 80 >"/dev/stderr"; 81 total = 0; 82 exit(1); 83 } 84} 85 86# (1) Load the built-in module address range data. 87# 88ARGIND == 1 { 89 ranges[FNR] = $0; 90 rcnt++; 91 next; 92} 93 94# (2) Annotate System.map symbols with module names. 95# 96ARGIND == 2 { 97 addr = addr2val($1); 98 name = $3; 99 100 while (addr >= mod_eaddr) { 101 if (sect_symb) { 102 if (sect_symb != name) 103 next; 104 105 sect_base = addr - sect_off; 106 if (dbg) 107 printf "[%s] BASE (%s) %016x - %016x = %016x\n", sect_name, sect_symb, addr, sect_off, sect_base >"/dev/stderr"; 108 sect_symb = 0; 109 } 110 111 if (++ridx > rcnt) 112 break; 113 114 $0 = ranges[ridx]; 115 sub(/-/, " "); 116 if ($4 != "=") { 117 sub(/-/, " "); 118 mod_saddr = strtonum("0x" $2) + sect_base; 119 mod_eaddr = strtonum("0x" $3) + sect_base; 120 $1 = $2 = $3 = ""; 121 sub(/^ +/, ""); 122 mod_name = $0; 123 124 if (dbg) 125 printf "[%s] %s from %016x to %016x\n", sect_name, mod_name, mod_saddr, mod_eaddr >"/dev/stderr"; 126 } else { 127 sect_name = $1; 128 sect_off = strtonum("0x" $2); 129 sect_symb = $5; 130 } 131 } 132 133 idx = addr"-"name; 134 if (addr >= mod_saddr && addr < mod_eaddr) 135 sym2mod[idx] = mod_name; 136 137 next; 138} 139 140# Once we are done annotating the System.map, we no longer need the ranges data. 141# 142FNR == 1 && ARGIND == 3 { 143 delete ranges; 144} 145 146# (3) Build a lookup map of built-in module names. 147# 148# Lines from modules.builtin will be like: 149# kernel/crypto/lzo-rle.ko 150# and we record the object name "crypto/lzo-rle". 151# 152ARGIND == 3 { 153 sub(/kernel\//, ""); # strip off "kernel/" prefix 154 sub(/\.ko$/, ""); # strip off .ko suffix 155 156 mods[$1] = 1; 157 next; 158} 159 160# (4) Get a list of symbols (per object). 161# 162# Symbols by object are read from vmlinux.map, with fallback to vmlinux.o.map 163# if vmlinux is found to have inked in vmlinux.o. 164# 165 166# If we were able to get the data we need from vmlinux.map, there is no need to 167# process vmlinux.o.map. 168# 169FNR == 1 && ARGIND == 5 && total > 0 { 170 if (dbg) 171 printf "Note: %s is not needed.\n", FILENAME >"/dev/stderr"; 172 exit; 173} 174 175# First determine whether we are dealing with a GNU ld or LLVM lld linker map. 176# 177ARGIND >= 4 && FNR == 1 && NF == 7 && $1 == "VMA" && $7 == "Symbol" { 178 map_is_lld = 1; 179 next; 180} 181 182# (LLD) Convert a section record fronm lld format to ld format. 183# 184ARGIND >= 4 && map_is_lld && NF == 5 && /[0-9] [^ ]+$/ { 185 $0 = $5 " 0x"$1 " 0x"$3 " load address 0x"$2; 186} 187 188# (LLD) Convert an object record from lld format to ld format. 189# 190ARGIND >= 4 && map_is_lld && NF == 5 && $5 ~ /:\(/ { 191 if (/\.a\(/ && !/ vmlinux\.a\(/) 192 next; 193 194 gsub(/\)/, ""); 195 sub(/:\(/, " "); 196 sub(/ vmlinux\.a\(/, " "); 197 $0 = " "$6 " 0x"$1 " 0x"$3 " " $5; 198} 199 200# (LLD) Convert a symbol record from lld format to ld format. 201# 202ARGIND >= 4 && map_is_lld && NF == 5 && $5 ~ /^[A-Za-z_][A-Za-z0-9_]*$/ { 203 $0 = " 0x" $1 " " $5; 204} 205 206# (LLD) We do not need any other ldd linker map records. 207# 208ARGIND >= 4 && map_is_lld && /^[0-9a-f]{16} / { 209 next; 210} 211 212# Handle section records with long section names (spilling onto a 2nd line). 213# 214ARGIND >= 4 && !map_is_lld && NF == 1 && /^[^ ]/ { 215 s = $0; 216 getline; 217 $0 = s " " $0; 218} 219 220# Next section - previous one is done. 221# 222ARGIND >= 4 && /^[^ ]/ { 223 sect = 0; 224} 225 226# Get the (top level) section name. 227# 228ARGIND >= 4 && /^\./ { 229 # Explicitly ignore a few sections that are not relevant here. 230 if ($1 ~ /^\.orc_/ || $1 ~ /_sites$/ || $1 ~ /\.percpu/) 231 next; 232 233 # Sections with a 0-address can be ignored as well (in vmlinux.map). 234 if (ARGIND == 4 && $2 ~ /^0x0+$/) 235 next; 236 237 sect = $1; 238 239 next; 240} 241 242# If we are not currently in a section we care about, ignore records. 243# 244!sect { 245 next; 246} 247 248# Handle object records with long section names (spilling onto a 2nd line). 249# 250ARGIND >= 4 && /^ [^ \*]/ && NF == 1 { 251 # If the section name is long, the remainder of the entry is found on 252 # the next line. 253 s = $0; 254 getline; 255 $0 = s " " $0; 256} 257 258# Objects linked in from static libraries are ignored. 259# If the object is vmlinux.o, we need to consult vmlinux.o.map for per-object 260# symbol information 261# 262ARGIND == 4 && /^ [^ ]/ && NF == 4 { 263 if ($4 ~ /\.a\(/) 264 next; 265 266 idx = sect":"$1; 267 if (!(idx in sect_addend)) { 268 sect_addend[idx] = addr2val($2); 269 if (dbg) 270 printf "ADDEND %s = %016x\n", idx, sect_addend[idx] >"/dev/stderr"; 271 } 272 if ($4 == "vmlinux.o") { 273 need_o_map = 1; 274 next; 275 } 276} 277 278# If data from vmlinux.o.map is needed, we only process section and object 279# records from vmlinux.map to determine which section we need to pay attention 280# to in vmlinux.o.map. So skip everything else from vmlinux.map. 281# 282ARGIND == 4 && need_o_map { 283 next; 284} 285 286# Get module information for the current object. 287# 288ARGIND >= 4 && /^ [^ ]/ && NF == 4 { 289 msect = $1; 290 mod_name = get_module_info($4); 291 mod_eaddr = addr2val($2) + addr2val($3); 292 293 next; 294} 295 296# Process a symbol record. 297# 298# Evaluate the module information obtained from vmlinux.map (or vmlinux.o.map) 299# as follows: 300# - For all symbols in a given object: 301# - If the symbol is annotated with the same module name(s) that the object 302# belongs to, count it as a match. 303# - Otherwise: 304# - If the symbol is known to have duplicates of which at least one is 305# in a built-in module, disregard it. 306# - If the symbol us not annotated with any module name(s) AND the 307# object belongs to built-in modules, count it as missing. 308# - Otherwise, count it as a mismatch. 309# 310ARGIND >= 4 && /^ / && NF == 2 && $1 ~ /^0x/ { 311 idx = sect":"msect; 312 if (!(idx in sect_addend)) 313 next; 314 315 addr = addr2val($1); 316 317 # Handle the rare but annoying case where a 0-size symbol is placed at 318 # the byte *after* the module range. Based on vmlinux.map it will be 319 # considered part of the current object, but it falls just beyond the 320 # module address range. Unfortunately, its address could be at the 321 # start of another built-in module, so the only safe thing to do is to 322 # ignore it. 323 if (mod_name && addr == mod_eaddr) 324 next; 325 326 # If we are processing vmlinux.o.map, we need to apply the base address 327 # of the section to the relative address on the record. 328 # 329 if (ARGIND == 5) 330 addr += sect_addend[idx]; 331 332 idx = addr"-"$2; 333 mod = ""; 334 if (idx in sym2mod) { 335 mod = sym2mod[idx]; 336 if (sym2mod[idx] == mod_name) { 337 mod_matches++; 338 matches++; 339 } else if (mod_name == "") { 340 print $2 " in " mod " (should NOT be)"; 341 mismatches++; 342 } else { 343 print $2 " in " mod " (should be " mod_name ")"; 344 mismatches++; 345 } 346 } else if (mod_name != "") { 347 print $2 " should be in " mod_name; 348 missing++; 349 } else 350 matches++; 351 352 total++; 353 354 next; 355} 356 357# Issue the comparison report. 358# 359END { 360 if (total) { 361 printf "Verification of %s:\n", ARGV[1]; 362 printf " Correct matches: %6d (%d%% of total)\n", matches, 100 * matches / total; 363 printf " Module matches: %6d (%d%% of matches)\n", mod_matches, 100 * mod_matches / matches; 364 printf " Mismatches: %6d (%d%% of total)\n", mismatches, 100 * mismatches / total; 365 printf " Missing: %6d (%d%% of total)\n", missing, 100 * missing / total; 366 367 if (mismatches || missing) 368 exit(1); 369 } 370} 371