[COMMIT osv master] loader.py: enhance to support debugging programs launched with Linux dynamic linker

[Commit Bot]

From: Waldemar Kozaczuk <jwkoz...@gmail.com>
Committer: Waldemar Kozaczuk <jwkoz...@gmail.com>
Branch: master

loader.py: enhance to support debugging programs launched with Linux dynamic linker

Signed-off-by: Waldemar Kozaczuk <jwkoz...@gmail.com>

---
diff --git a/scripts/loader.py b/scripts/loader.py
--- a/scripts/loader.py
+++ b/scripts/loader.py
@@ -21,6 +21,8 @@
format_time)
from osv import trace, debug

+from manifest_common import add_var, expand, unsymlink, read_manifest, defines
+
virtio_driver_type = gdb.lookup_type('virtio::virtio_driver')

class status_enum_class(object):
@@ -131,33 +133,40 @@ def __init__(self):
# Load data from usr.manifest in build_dir
mm_path = os.path.join(build_dir, 'usr.manifest')
try:
- self.data = open(mm_path).read().split('\n')
+ _manifest = read_manifest(mm_path)
+ self.guest_to_host_map = list(expand(_manifest))
+ self.guest_to_host_map = [(x, unsymlink(y % defines)) for (x, y) in self.guest_to_host_map]
except IOError:
- self.data = []
+ self.guest_to_host_map = []

def find(self, path):
'''Try to locate file with help of usr.manifest'''
- files = [ff.split(':', 1)[1].strip() for ff in self.data if ff.split(':', 1)[0].strip() == path]
+ files = [host for (guest, host) in self.guest_to_host_map if guest == path]
if files:
- file = files[-1] # the last line in usr.manifest wins
+ host_file = files[-1] # the last line in usr.manifest wins
else:
- file = ""
- file = self.resolve_symlink(file)
- print('manifest.find_file: path=%s, found file=%s' % (path, file))
+ host_file = ""
+ host_file = self.resolve_host_file(host_file)
+ print('manifest.find_file: path=%s, found file=%s' % (path, host_file))
# usr.manifest contains lines like "%(gccbase)s/lib64/libgcc_s.so.1" too.
# Filter out such cases.
- if os.path.exists(file):
- return file
+ if os.path.exists(host_file):
+ return host_file
else:
return ""

- def resolve_symlink(self, file):
- '''If file is a symlink, try to resolve it with help of usr.manifest'''
+ def resolve_host_file(self, file):
resolved_file = file
+ #Handle symlink
if file.startswith('->'):
- path = file[2:]
- resolved_file = self.find(path)
- # print('manifest.resolve_symlink: file=%s, resolved_file=%s' % (file, resolved_file))
+ resolved_file = self.find(file[2:].strip())
+ else:
+ resolved_file = file
+ #Handle path to build directory
+ if resolved_file.startswith('.'):
+ resolved_file = os.path.join(build_dir, resolved_file[2:])
+ if not resolved_file.startswith('/'):
+ resolved_file = os.path.join(build_dir, resolved_file)
return resolved_file

manifest = Manifest()
@@ -689,6 +698,7 @@ def __init__(self):
gdb.COMMAND_USER, gdb.COMPLETE_NONE)
def invoke(self, arg, from_tty):
syminfo_resolver.clear_cache()
+ object_paths = set()
for obj in read_vector(gdb.lookup_global_symbol('elf::program::s_objs').value()):
base = to_int(obj['_base'])
obj_path = obj['_pathname']['_M_dataplus']['_M_p'].string()
@@ -697,8 +707,30 @@ def invoke(self, arg, from_tty):
print('ERROR: Unable to locate object file for:', obj_path, hex(base))
else:
print(path, hex(base))
+ object_paths.add(path)
load_elf(path, base)

+ for vma in vma_list():
+ start = ulong(vma['_range']['_start'])
+ flags = flagstr(ulong(vma['_flags']))
+ perm = permstr(ulong(vma['_perm']))
+
+ if 'F' in flags:
+ file_vma = vma.cast(gdb.lookup_type('mmu::file_vma').pointer())
+ file_ptr = file_vma['_file']['px'].cast(gdb.lookup_type('file').pointer())
+ dentry_ptr = file_ptr['f_dentry']['px'].cast(gdb.lookup_type('dentry').pointer())
+ file_path = dentry_ptr['d_path'].string()
+ path = translate(file_path)
+ if not path:
+ print('ERROR: Unable to locate object file for:', file_path, hex(start))
+ elif path not in object_paths:
+ print(path, hex(start))
+ try:
+ load_elf(path, start)
+ object_paths.add(path)
+ except gdb.error:
+ print('ERROR: Not an ELF file', path, hex(start))
+
class osv_load_elf(gdb.Command):
def __init__(self):
gdb.Command.__init__(self, 'osv load-elf',