migration: Fix analyze-migration.py when ignore-shared is used

The script is currently broken when the x-ignore-shared capability is
used:

Traceback (most recent call last):
  File "./scripts/analyze-migration.py", line 656, in <module>
    dump.read(dump_memory = args.memory)
  File "./scripts/analyze-migration.py", line 593, in read
    section.read()
  File "./scripts/analyze-migration.py", line 163, in read
    self.name = self.file.readstr(len = namelen)
  File "./scripts/analyze-migration.py", line 53, in readstr
    return self.readvar(len).decode('utf-8')
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x82 in position 55: invalid start byte

We're currently adding data to the middle of the ram section depending
on the presence of the capability. As a consequence, any code loading
the ram section needs to know about capabilities so it can interpret
the stream.

Skip the byte that's added when x-ignore-shared is used to fix the
script.

Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231009184326.15777-5-farosas@suse.de>
This commit is contained in:
Fabiano Rosas 2023-10-09 15:43:24 -03:00 committed by Juan Quintela
parent 31499a9dc1
commit ff40c7f0b7

View File

@ -123,6 +123,7 @@ class RamSection(object):
self.TARGET_PAGE_SIZE = ramargs['page_size']
self.dump_memory = ramargs['dump_memory']
self.write_memory = ramargs['write_memory']
self.ignore_shared = ramargs['ignore_shared']
self.sizeinfo = collections.OrderedDict()
self.data = collections.OrderedDict()
self.data['section sizes'] = self.sizeinfo
@ -169,6 +170,8 @@ class RamSection(object):
f.truncate(0)
f.truncate(len)
self.files[self.name] = f
if self.ignore_shared:
mr_addr = self.file.read64()
flags &= ~self.RAM_SAVE_FLAG_MEM_SIZE
if flags & self.RAM_SAVE_FLAG_COMPRESS:
@ -572,6 +575,7 @@ class MigrationDump(object):
ramargs['page_size'] = self.vmsd_desc['page_size']
ramargs['dump_memory'] = dump_memory
ramargs['write_memory'] = write_memory
ramargs['ignore_shared'] = False
self.section_classes[('ram',0)][1] = ramargs
while True:
@ -582,6 +586,7 @@ class MigrationDump(object):
config_desc = self.vmsd_desc.get('configuration')
section = ConfigurationSection(file, config_desc)
section.read()
ramargs['ignore_shared'] = section.has_capability('x-ignore-shared')
elif section_type == self.QEMU_VM_SECTION_START or section_type == self.QEMU_VM_SECTION_FULL:
section_id = file.read32()
name = file.readstr()