u-boot/tools/binman/elf_test.py
Simon Glass 7c15013639 binman: tegra: Adjust symbol calculation depending on end-at-4gb
A recent change adjusted the symbol calculation to work on x86 but broke
it for Tegra. In fact this is because they have different needs.

On x86 devices the code is linked to a ROM address and the end-at-4gb
property is used for the image. In this case there is no need to add the
base address of the image, since the base address is already built into
the offset and image-pos properties.

On other devices we must add the base address since the offsets start at
zero.

In addition the base address is currently added to the 'offset' and 'size'
values. It should in fact only be added to 'image-pos', since 'offset' is
relative to its parent and 'size' is not actually an address. This code
should have been adjusted when support for 'image-pos' and 'size' was
added, but it was not.

To correct these problems:
- move the code that handles adding the base address to section.py, which
  can check the end-at-4gb property and which property
  (offset/size/image-pos) is being read
- add the base address only when needed (only for image-pos and not if the
  image uses end-at-4gb)
- add a note to the documentation
- add a separate test to cover x86 behaviour

Fixes: 15c981cc (binman: Correct symbol calculation with non-zero image base)

Signed-off-by: Simon Glass <sjg@chromium.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
2019-11-11 14:20:35 -05:00

218 lines
7.5 KiB
Python

# SPDX-License-Identifier: GPL-2.0+
# Copyright (c) 2017 Google, Inc
# Written by Simon Glass <sjg@chromium.org>
#
# Test for the elf module
import os
import shutil
import sys
import tempfile
import unittest
import command
import elf
import test_util
import tools
import tout
binman_dir = os.path.dirname(os.path.realpath(sys.argv[0]))
class FakeEntry:
"""A fake Entry object, usedfor testing
This supports an entry with a given size.
"""
def __init__(self, contents_size):
self.contents_size = contents_size
self.data = tools.GetBytes(ord('a'), contents_size)
def GetPath(self):
return 'entry_path'
class FakeSection:
"""A fake Section object, used for testing
This has the minimum feature set needed to support testing elf functions.
A LookupSymbol() function is provided which returns a fake value for amu
symbol requested.
"""
def __init__(self, sym_value=1):
self.sym_value = sym_value
def GetPath(self):
return 'section_path'
def LookupSymbol(self, name, weak, msg, base_addr):
"""Fake implementation which returns the same value for all symbols"""
return self.sym_value
def BuildElfTestFiles(target_dir):
"""Build ELF files used for testing in binman
This compiles and links the test files into the specified directory. It the
Makefile and source files in the binman test/ directory.
Args:
target_dir: Directory to put the files into
"""
if not os.path.exists(target_dir):
os.mkdir(target_dir)
testdir = os.path.join(binman_dir, 'test')
# If binman is involved from the main U-Boot Makefile the -r and -R
# flags are set in MAKEFLAGS. This prevents this Makefile from working
# correctly. So drop any make flags here.
if 'MAKEFLAGS' in os.environ:
del os.environ['MAKEFLAGS']
tools.Run('make', '-C', target_dir, '-f',
os.path.join(testdir, 'Makefile'), 'SRC=%s/' % testdir)
class TestElf(unittest.TestCase):
@classmethod
def setUpClass(cls):
cls._indir = tempfile.mkdtemp(prefix='elf.')
tools.SetInputDirs(['.'])
BuildElfTestFiles(cls._indir)
@classmethod
def tearDownClass(cls):
if cls._indir:
shutil.rmtree(cls._indir)
@classmethod
def ElfTestFile(cls, fname):
return os.path.join(cls._indir, fname)
def testAllSymbols(self):
"""Test that we can obtain a symbol from the ELF file"""
fname = self.ElfTestFile('u_boot_ucode_ptr')
syms = elf.GetSymbols(fname, [])
self.assertIn('.ucode', syms)
def testRegexSymbols(self):
"""Test that we can obtain from the ELF file by regular expression"""
fname = self.ElfTestFile('u_boot_ucode_ptr')
syms = elf.GetSymbols(fname, ['ucode'])
self.assertIn('.ucode', syms)
syms = elf.GetSymbols(fname, ['missing'])
self.assertNotIn('.ucode', syms)
syms = elf.GetSymbols(fname, ['missing', 'ucode'])
self.assertIn('.ucode', syms)
def testMissingFile(self):
"""Test that a missing file is detected"""
entry = FakeEntry(10)
section = FakeSection()
with self.assertRaises(ValueError) as e:
syms = elf.LookupAndWriteSymbols('missing-file', entry, section)
self.assertIn("Filename 'missing-file' not found in input path",
str(e.exception))
def testOutsideFile(self):
"""Test a symbol which extends outside the entry area is detected"""
entry = FakeEntry(10)
section = FakeSection()
elf_fname = self.ElfTestFile('u_boot_binman_syms')
with self.assertRaises(ValueError) as e:
syms = elf.LookupAndWriteSymbols(elf_fname, entry, section)
self.assertIn('entry_path has offset 4 (size 8) but the contents size '
'is a', str(e.exception))
def testMissingImageStart(self):
"""Test that we detect a missing __image_copy_start symbol
This is needed to mark the start of the image. Without it we cannot
locate the offset of a binman symbol within the image.
"""
entry = FakeEntry(10)
section = FakeSection()
elf_fname = self.ElfTestFile('u_boot_binman_syms_bad')
self.assertEqual(elf.LookupAndWriteSymbols(elf_fname, entry, section),
None)
def testBadSymbolSize(self):
"""Test that an attempt to use an 8-bit symbol are detected
Only 32 and 64 bits are supported, since we need to store an offset
into the image.
"""
entry = FakeEntry(10)
section = FakeSection()
elf_fname =self.ElfTestFile('u_boot_binman_syms_size')
with self.assertRaises(ValueError) as e:
syms = elf.LookupAndWriteSymbols(elf_fname, entry, section)
self.assertIn('has size 1: only 4 and 8 are supported',
str(e.exception))
def testNoValue(self):
"""Test the case where we have no value for the symbol
This should produce -1 values for all thress symbols, taking up the
first 16 bytes of the image.
"""
entry = FakeEntry(24)
section = FakeSection(sym_value=None)
elf_fname = self.ElfTestFile('u_boot_binman_syms')
syms = elf.LookupAndWriteSymbols(elf_fname, entry, section)
self.assertEqual(tools.GetBytes(255, 20) + tools.GetBytes(ord('a'), 4),
entry.data)
def testDebug(self):
"""Check that enabling debug in the elf module produced debug output"""
try:
tout.Init(tout.DEBUG)
entry = FakeEntry(20)
section = FakeSection()
elf_fname = self.ElfTestFile('u_boot_binman_syms')
with test_util.capture_sys_output() as (stdout, stderr):
syms = elf.LookupAndWriteSymbols(elf_fname, entry, section)
self.assertTrue(len(stdout.getvalue()) > 0)
finally:
tout.Init(tout.WARNING)
def testMakeElf(self):
"""Test for the MakeElf function"""
outdir = tempfile.mkdtemp(prefix='elf.')
expected_text = b'1234'
expected_data = b'wxyz'
elf_fname = os.path.join(outdir, 'elf')
bin_fname = os.path.join(outdir, 'bin')
# Make an Elf file and then convert it to a fkat binary file. This
# should produce the original data.
elf.MakeElf(elf_fname, expected_text, expected_data)
stdout = command.Output('objcopy', '-O', 'binary', elf_fname, bin_fname)
with open(bin_fname, 'rb') as fd:
data = fd.read()
self.assertEqual(expected_text + expected_data, data)
shutil.rmtree(outdir)
def testDecodeElf(self):
"""Test for the MakeElf function"""
if not elf.ELF_TOOLS:
self.skipTest('Python elftools not available')
outdir = tempfile.mkdtemp(prefix='elf.')
expected_text = b'1234'
expected_data = b'wxyz'
elf_fname = os.path.join(outdir, 'elf')
elf.MakeElf(elf_fname, expected_text, expected_data)
data = tools.ReadFile(elf_fname)
load = 0xfef20000
entry = load + 2
expected = expected_text + expected_data
self.assertEqual(elf.ElfInfo(expected, load, entry, len(expected)),
elf.DecodeElf(data, 0))
self.assertEqual(elf.ElfInfo(b'\0\0' + expected[2:],
load, entry, len(expected)),
elf.DecodeElf(data, load + 2))
shutil.rmtree(outdir)
if __name__ == '__main__':
unittest.main()