| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | #!/usr/bin/perl | 
 | 2 |  | 
 | 3 | use File::Basename; | 
 | 4 | use Math::BigInt; | 
 | 5 | use Getopt::Long; | 
 | 6 |  | 
 | 7 | # Copyright 2008, Intel Corporation | 
 | 8 | # | 
 | 9 | # This file is part of the Linux kernel | 
 | 10 | # | 
 | 11 | # This program file is free software; you can redistribute it and/or modify it | 
 | 12 | # under the terms of the GNU General Public License as published by the | 
 | 13 | # Free Software Foundation; version 2 of the License. | 
 | 14 | # | 
 | 15 | # Authors: | 
 | 16 | # 	Arjan van de Ven <arjan@linux.intel.com> | 
 | 17 |  | 
 | 18 |  | 
 | 19 | my $cross_compile = ""; | 
 | 20 | my $vmlinux_name = ""; | 
 | 21 | my $modulefile = ""; | 
 | 22 |  | 
 | 23 | # Get options | 
 | 24 | Getopt::Long::GetOptions( | 
 | 25 | 	'cross-compile|c=s'	=> \$cross_compile, | 
 | 26 | 	'module|m=s'		=> \$modulefile, | 
 | 27 | 	'help|h'		=> \&usage, | 
 | 28 | ) || usage (); | 
 | 29 | my $vmlinux_name = $ARGV[0]; | 
 | 30 | if (!defined($vmlinux_name)) { | 
 | 31 | 	my $kerver = `uname -r`; | 
 | 32 | 	chomp($kerver); | 
 | 33 | 	$vmlinux_name = "/lib/modules/$kerver/build/vmlinux"; | 
 | 34 | 	print "No vmlinux specified, assuming $vmlinux_name\n"; | 
 | 35 | } | 
 | 36 | my $filename = $vmlinux_name; | 
 | 37 |  | 
 | 38 | # Parse the oops to find the EIP value | 
 | 39 |  | 
 | 40 | my $target = "0"; | 
 | 41 | my $function; | 
 | 42 | my $module = ""; | 
 | 43 | my $func_offset = 0; | 
 | 44 | my $vmaoffset = 0; | 
 | 45 |  | 
 | 46 | my %regs; | 
 | 47 |  | 
 | 48 |  | 
 | 49 | sub parse_x86_regs | 
 | 50 | { | 
 | 51 | 	my ($line) = @_; | 
 | 52 | 	if ($line =~ /EAX: ([0-9a-f]+) EBX: ([0-9a-f]+) ECX: ([0-9a-f]+) EDX: ([0-9a-f]+)/) { | 
 | 53 | 		$regs{"%eax"} = $1; | 
 | 54 | 		$regs{"%ebx"} = $2; | 
 | 55 | 		$regs{"%ecx"} = $3; | 
 | 56 | 		$regs{"%edx"} = $4; | 
 | 57 | 	} | 
 | 58 | 	if ($line =~ /ESI: ([0-9a-f]+) EDI: ([0-9a-f]+) EBP: ([0-9a-f]+) ESP: ([0-9a-f]+)/) { | 
 | 59 | 		$regs{"%esi"} = $1; | 
 | 60 | 		$regs{"%edi"} = $2; | 
 | 61 | 		$regs{"%esp"} = $4; | 
 | 62 | 	} | 
 | 63 | 	if ($line =~ /RAX: ([0-9a-f]+) RBX: ([0-9a-f]+) RCX: ([0-9a-f]+)/) { | 
 | 64 | 		$regs{"%eax"} = $1; | 
 | 65 | 		$regs{"%ebx"} = $2; | 
 | 66 | 		$regs{"%ecx"} = $3; | 
 | 67 | 	} | 
 | 68 | 	if ($line =~ /RDX: ([0-9a-f]+) RSI: ([0-9a-f]+) RDI: ([0-9a-f]+)/) { | 
 | 69 | 		$regs{"%edx"} = $1; | 
 | 70 | 		$regs{"%esi"} = $2; | 
 | 71 | 		$regs{"%edi"} = $3; | 
 | 72 | 	} | 
 | 73 | 	if ($line =~ /RBP: ([0-9a-f]+) R08: ([0-9a-f]+) R09: ([0-9a-f]+)/) { | 
 | 74 | 		$regs{"%r08"} = $2; | 
 | 75 | 		$regs{"%r09"} = $3; | 
 | 76 | 	} | 
 | 77 | 	if ($line =~ /R10: ([0-9a-f]+) R11: ([0-9a-f]+) R12: ([0-9a-f]+)/) { | 
 | 78 | 		$regs{"%r10"} = $1; | 
 | 79 | 		$regs{"%r11"} = $2; | 
 | 80 | 		$regs{"%r12"} = $3; | 
 | 81 | 	} | 
 | 82 | 	if ($line =~ /R13: ([0-9a-f]+) R14: ([0-9a-f]+) R15: ([0-9a-f]+)/) { | 
 | 83 | 		$regs{"%r13"} = $1; | 
 | 84 | 		$regs{"%r14"} = $2; | 
 | 85 | 		$regs{"%r15"} = $3; | 
 | 86 | 	} | 
 | 87 | } | 
 | 88 |  | 
 | 89 | sub reg_name | 
 | 90 | { | 
 | 91 | 	my ($reg) = @_; | 
 | 92 | 	$reg =~ s/r(.)x/e\1x/; | 
 | 93 | 	$reg =~ s/r(.)i/e\1i/; | 
 | 94 | 	$reg =~ s/r(.)p/e\1p/; | 
 | 95 | 	return $reg; | 
 | 96 | } | 
 | 97 |  | 
 | 98 | sub process_x86_regs | 
 | 99 | { | 
 | 100 | 	my ($line, $cntr) = @_; | 
 | 101 | 	my $str = ""; | 
 | 102 | 	if (length($line) < 40) { | 
 | 103 | 		return ""; # not an asm istruction | 
 | 104 | 	} | 
 | 105 |  | 
 | 106 | 	# find the arguments to the instruction | 
 | 107 | 	if ($line =~ /([0-9a-zA-Z\,\%\(\)\-\+]+)$/) { | 
 | 108 | 		$lastword = $1; | 
 | 109 | 	} else { | 
 | 110 | 		return ""; | 
 | 111 | 	} | 
 | 112 |  | 
 | 113 | 	# we need to find the registers that get clobbered, | 
 | 114 | 	# since their value is no longer relevant for previous | 
 | 115 | 	# instructions in the stream. | 
 | 116 |  | 
 | 117 | 	$clobber = $lastword; | 
 | 118 | 	# first, remove all memory operands, they're read only | 
 | 119 | 	$clobber =~ s/\([a-z0-9\%\,]+\)//g; | 
 | 120 | 	# then, remove everything before the comma, thats the read part | 
 | 121 | 	$clobber =~ s/.*\,//g; | 
 | 122 |  | 
 | 123 | 	# if this is the instruction that faulted, we haven't actually done | 
 | 124 | 	# the write yet... nothing is clobbered. | 
 | 125 | 	if ($cntr == 0) { | 
 | 126 | 		$clobber = ""; | 
 | 127 | 	} | 
 | 128 |  | 
 | 129 | 	foreach $reg (keys(%regs)) { | 
 | 130 | 		my $clobberprime = reg_name($clobber); | 
 | 131 | 		my $lastwordprime = reg_name($lastword); | 
 | 132 | 		my $val = $regs{$reg}; | 
 | 133 | 		if ($val =~ /^[0]+$/) { | 
 | 134 | 			$val = "0"; | 
 | 135 | 		} else { | 
 | 136 | 			$val =~ s/^0*//; | 
 | 137 | 		} | 
 | 138 |  | 
 | 139 | 		# first check if we're clobbering this register; if we do | 
 | 140 | 		# we print it with a =>, and then delete its value | 
 | 141 | 		if ($clobber =~ /$reg/ || $clobberprime =~ /$reg/) { | 
 | 142 | 			if (length($val) > 0) { | 
 | 143 | 				$str = $str . " $reg => $val "; | 
 | 144 | 			} | 
 | 145 | 			$regs{$reg} = ""; | 
 | 146 | 			$val = ""; | 
 | 147 | 		} | 
 | 148 | 		# now check if we're reading this register | 
 | 149 | 		if ($lastword =~ /$reg/ || $lastwordprime =~ /$reg/) { | 
 | 150 | 			if (length($val) > 0) { | 
 | 151 | 				$str = $str . " $reg = $val "; | 
 | 152 | 			} | 
 | 153 | 		} | 
 | 154 | 	} | 
 | 155 | 	return $str; | 
 | 156 | } | 
 | 157 |  | 
 | 158 | # parse the oops | 
 | 159 | while (<STDIN>) { | 
 | 160 | 	my $line = $_; | 
 | 161 | 	if ($line =~ /EIP: 0060:\[\<([a-z0-9]+)\>\]/) { | 
 | 162 | 		$target = $1; | 
 | 163 | 	} | 
 | 164 | 	if ($line =~ /RIP: 0010:\[\<([a-z0-9]+)\>\]/) { | 
 | 165 | 		$target = $1; | 
 | 166 | 	} | 
 | 167 | 	if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+0x([0-9a-f]+)\/0x[a-f0-9]/) { | 
 | 168 | 		$function = $1; | 
 | 169 | 		$func_offset = $2; | 
 | 170 | 	} | 
 | 171 | 	if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+0x([0-9a-f]+)\/0x[a-f0-9]/) { | 
 | 172 | 		$function = $1; | 
 | 173 | 		$func_offset = $2; | 
 | 174 | 	} | 
 | 175 |  | 
 | 176 | 	# check if it's a module | 
 | 177 | 	if ($line =~ /EIP is at ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) { | 
 | 178 | 		$module = $3; | 
 | 179 | 	} | 
 | 180 | 	if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\]  \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]+\W\[([a-zA-Z0-9\_\-]+)\]/) { | 
 | 181 | 		$module = $3; | 
 | 182 | 	} | 
 | 183 | 	parse_x86_regs($line); | 
 | 184 | } | 
 | 185 |  | 
 | 186 | my $decodestart = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$func_offset"); | 
 | 187 | my $decodestop = Math::BigInt->from_hex("0x$target") + 8192; | 
 | 188 | if ($target eq "0") { | 
 | 189 | 	print "No oops found!\n"; | 
 | 190 | 	usage(); | 
 | 191 | } | 
 | 192 |  | 
 | 193 | # if it's a module, we need to find the .ko file and calculate a load offset | 
 | 194 | if ($module ne "") { | 
 | 195 | 	if ($modulefile eq "") { | 
 | 196 | 		$modulefile = `modinfo -F filename $module`; | 
 | 197 | 		chomp($modulefile); | 
 | 198 | 	} | 
 | 199 | 	$filename = $modulefile; | 
 | 200 | 	if ($filename eq "") { | 
 | 201 | 		print "Module .ko file for $module not found. Aborting\n"; | 
 | 202 | 		exit; | 
 | 203 | 	} | 
 | 204 | 	# ok so we found the module, now we need to calculate the vma offset | 
 | 205 | 	open(FILE, $cross_compile."objdump -dS $filename |") || die "Cannot start objdump"; | 
 | 206 | 	while (<FILE>) { | 
 | 207 | 		if ($_ =~ /^([0-9a-f]+) \<$function\>\:/) { | 
 | 208 | 			my $fu = $1; | 
 | 209 | 			$vmaoffset = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$fu") - Math::BigInt->from_hex("0x$func_offset"); | 
 | 210 | 		} | 
 | 211 | 	} | 
 | 212 | 	close(FILE); | 
 | 213 | } | 
 | 214 |  | 
 | 215 | my $counter = 0; | 
 | 216 | my $state   = 0; | 
 | 217 | my $center  = -1; | 
 | 218 | my @lines; | 
 | 219 | my @reglines; | 
 | 220 |  | 
 | 221 | sub InRange { | 
 | 222 | 	my ($address, $target) = @_; | 
 | 223 | 	my $ad = "0x".$address; | 
 | 224 | 	my $ta = "0x".$target; | 
 | 225 | 	my $delta = Math::BigInt->from_hex($ad) - Math::BigInt->from_hex($ta); | 
 | 226 |  | 
 | 227 | 	if (($delta > -4096) && ($delta < 4096)) { | 
 | 228 | 		return 1; | 
 | 229 | 	} | 
 | 230 | 	return 0; | 
 | 231 | } | 
 | 232 |  | 
 | 233 |  | 
 | 234 |  | 
 | 235 | # first, parse the input into the lines array, but to keep size down, | 
 | 236 | # we only do this for 4Kb around the sweet spot | 
 | 237 |  | 
 | 238 | open(FILE, $cross_compile."objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump"; | 
 | 239 |  | 
 | 240 | while (<FILE>) { | 
 | 241 | 	my $line = $_; | 
 | 242 | 	chomp($line); | 
 | 243 | 	if ($state == 0) { | 
 | 244 | 		if ($line =~ /^([a-f0-9]+)\:/) { | 
 | 245 | 			if (InRange($1, $target)) { | 
 | 246 | 				$state = 1; | 
 | 247 | 			} | 
 | 248 | 		} | 
 | 249 | 	} | 
 | 250 | 	if ($state == 1) { | 
 | 251 | 		if ($line =~ /^([a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+)\:/) { | 
 | 252 | 			my $val = $1; | 
 | 253 | 			if (!InRange($val, $target)) { | 
 | 254 | 				last; | 
 | 255 | 			} | 
 | 256 | 			if ($val eq $target) { | 
 | 257 | 				$center = $counter; | 
 | 258 | 			} | 
 | 259 | 		} | 
 | 260 | 		$lines[$counter] = $line; | 
 | 261 |  | 
 | 262 | 		$counter = $counter + 1; | 
 | 263 | 	} | 
 | 264 | } | 
 | 265 |  | 
 | 266 | close(FILE); | 
 | 267 |  | 
 | 268 | if ($counter == 0) { | 
 | 269 | 	print "No matching code found \n"; | 
 | 270 | 	exit; | 
 | 271 | } | 
 | 272 |  | 
 | 273 | if ($center == -1) { | 
 | 274 | 	print "No matching code found \n"; | 
 | 275 | 	exit; | 
 | 276 | } | 
 | 277 |  | 
 | 278 | my $start; | 
 | 279 | my $finish; | 
 | 280 | my $codelines = 0; | 
 | 281 | my $binarylines = 0; | 
 | 282 | # now we go up and down in the array to find how much we want to print | 
 | 283 |  | 
 | 284 | $start = $center; | 
 | 285 |  | 
 | 286 | while ($start > 1) { | 
 | 287 | 	$start = $start - 1; | 
 | 288 | 	my $line = $lines[$start]; | 
 | 289 | 	if ($line =~ /^([a-f0-9]+)\:/) { | 
 | 290 | 		$binarylines = $binarylines + 1; | 
 | 291 | 	} else { | 
 | 292 | 		$codelines = $codelines + 1; | 
 | 293 | 	} | 
 | 294 | 	if ($codelines > 10) { | 
 | 295 | 		last; | 
 | 296 | 	} | 
 | 297 | 	if ($binarylines > 20) { | 
 | 298 | 		last; | 
 | 299 | 	} | 
 | 300 | } | 
 | 301 |  | 
 | 302 |  | 
 | 303 | $finish = $center; | 
 | 304 | $codelines = 0; | 
 | 305 | $binarylines = 0; | 
 | 306 | while ($finish < $counter) { | 
 | 307 | 	$finish = $finish + 1; | 
 | 308 | 	my $line = $lines[$finish]; | 
 | 309 | 	if ($line =~ /^([a-f0-9]+)\:/) { | 
 | 310 | 		$binarylines = $binarylines + 1; | 
 | 311 | 	} else { | 
 | 312 | 		$codelines = $codelines + 1; | 
 | 313 | 	} | 
 | 314 | 	if ($codelines > 10) { | 
 | 315 | 		last; | 
 | 316 | 	} | 
 | 317 | 	if ($binarylines > 20) { | 
 | 318 | 		last; | 
 | 319 | 	} | 
 | 320 | } | 
 | 321 |  | 
 | 322 |  | 
 | 323 | my $i; | 
 | 324 |  | 
 | 325 |  | 
 | 326 | # start annotating the registers in the asm. | 
 | 327 | # this goes from the oopsing point back, so that the annotator | 
 | 328 | # can track (opportunistically) which registers got written and | 
 | 329 | # whos value no longer is relevant. | 
 | 330 |  | 
 | 331 | $i = $center; | 
 | 332 | while ($i >= $start) { | 
 | 333 | 	$reglines[$i] = process_x86_regs($lines[$i], $center - $i); | 
 | 334 | 	$i = $i - 1; | 
 | 335 | } | 
 | 336 |  | 
 | 337 | $i = $start; | 
 | 338 | while ($i < $finish) { | 
 | 339 | 	my $line; | 
 | 340 | 	if ($i == $center) { | 
 | 341 | 		$line =  "*$lines[$i] "; | 
 | 342 | 	} else { | 
 | 343 | 		$line =  " $lines[$i] "; | 
 | 344 | 	} | 
 | 345 | 	print $line; | 
 | 346 | 	if (defined($reglines[$i]) && length($reglines[$i]) > 0) { | 
 | 347 | 		my $c = 60 - length($line); | 
 | 348 | 		while ($c > 0) { print " "; $c = $c - 1; }; | 
 | 349 | 		print "| $reglines[$i]"; | 
 | 350 | 	} | 
 | 351 | 	if ($i == $center) { | 
 | 352 | 		print "<--- faulting instruction"; | 
 | 353 | 	} | 
 | 354 | 	print "\n"; | 
 | 355 | 	$i = $i +1; | 
 | 356 | } | 
 | 357 |  | 
 | 358 | sub usage { | 
 | 359 | 	print <<EOT; | 
 | 360 | Usage: | 
 | 361 |   dmesg | perl $0 [OPTION] [VMLINUX] | 
 | 362 |  | 
 | 363 | OPTION: | 
 | 364 |   -c, --cross-compile CROSS_COMPILE	Specify the prefix used for toolchain. | 
 | 365 |   -m, --module MODULE_DIRNAME		Specify the module filename. | 
 | 366 |   -h, --help				Help. | 
 | 367 | EOT | 
 | 368 | 	exit; | 
 | 369 | } | 
 | 370 |  |