crash.types.slab module

class crash.types.slab.KmemCache(name: str, gdb_obj: Value)

Bases: ABC

SLUB = False

SlabFlags = {'ACCOUNT': 67108864, 'CACHE_DMA': 16384, 'CONSISTENCY_CHECKS': 256, 'DEBUG_OBJECTS': 4194304, 'FAILSLAB': 33554432, 'HWCACHE_ALIGN': 8192, 'MEM_SPREAD': 1048576, 'NOLEAKTRACE': 8388608, 'NOTRACK': 16777216, 'PANIC': 262144, 'POISON': 2048, 'RECLAIM_ACCOUNT': 131072, 'RED_ZONE': 1024, 'STORE_USER': 65536, 'TRACE': 2097152, 'TYPESAFE_BY_RCU': 524288}

alien_cache_type_exists = False

buffer_size_name = None

abstract check_all() → None

classmethod check_kmem_cache_node_type(gdbtype: Type) → None

classmethod check_kmem_cache_type(gdbtype: Type) → None

classmethod create(name: str, gdb_obj: Value) → KmemCache

abstract get_allocated_objects() → Iterable[int]

has_flag(flag_name: str) → bool

head_name = 'list'

abstract list_all(verbosity: int) → None

nodelists_name = None

percpu_cache = None

percpu_name = None

slub_debug_compiled = True

tracks_full_slabs() → bool

exception crash.types.slab.KmemCacheNotFound

Bases: RuntimeError

The specified kmem_cache could not be found.

class crash.types.slab.KmemCacheSLAB(name: str, gdb_obj: Value)

Bases: KmemCache

buffer_size: int

check_all() → None

check_array_caches() → None

get_allocated_objects() → Iterable[int]

get_array_caches() → Dict[int, Dict[str, int | str]]

get_slabs_of_type(node: Value, slabtype: int, reverse: bool = False, exact_cycles: bool = False) → Iterable[SlabSLAB]

list_all(verbosity: int) → None

classmethod setup_alien_cache_type(gdbtype: Type) → None

slab_list_fullname = {0: 'slabs_partial', 1: 'slabs_full', 2: 'slabs_free'}

slab_list_name = {0: 'partial', 1: 'full', 2: 'free'}

class crash.types.slab.KmemCacheSLUB(name: str, gdb_obj: Value)

Bases: KmemCache

check_all() → None

get_allocated_objects() → Iterable[int]

list_all(verbosity: int) → None

process_all(flags: ProcessingFlags) → None

red_left_pad() → int

slub_process_once() → None

class crash.types.slab.ProcessingFlags(print_level: int = 0)

Bases: object

class crash.types.slab.Slab(gdb_obj: Value, kmem_cache: KmemCache)

Bases: ABC

A common superclass representing a slab, i.e. a collection of objects on a single (possibly high-order) page.

Parameters:

• gdb_obj – The structure to wrap, of type struct slab or struct page.

• kmem_cache – The kmem_cache instance the slab belongs to.

gdb_obj

The structure being wrapped. The value is of type struct slab or struct page.

Type:

gdb.Value

address

Address of the structure being wrapped.

Type:

int

kmem_cache

The cache the slab belongs to.

Type:

KmemCache

free

Set of addresses of free objects in the slab.

Type:

Set[int]

nr_objects (

obj:`int): Total number of objects in the slab.

nr_inuse (

obj:`int): Number of allocated objects in the slab.

nr_free (

obj:`int): Number of free objects in the slab.

abstract contains_obj(addr: int) → Tuple[bool, int, str | None]

Returns whether the slab contains an object at given address.

Parameters:

addr – Address of object to check.

Returns:

A tuple with object information. contains (bool): Whether addr points inside valid object

range.

address (int): Starting address of the object. Might be

returned even if contains is False, when addr falls e.g. into a red zone or padding of an object.

description (str): Optional description of where addr points

to in case it’s not a valid object.

Return type:

(contains, address, description)

abstract find_obj(addr: int) → int | None

Returns starting address of object in slab.

Parameters:

addr – Address of the object to find.

Returns:

Starting address of the object, or None if the address

does not fall into the slab’s range. Note that while object address might be returned, addr might still be outside of valid range. Use contains_obj() to verify.

Return type:

int

abstract classmethod from_list_head(list_head: Value, kmem_cache: KmemCache) → Slab

Create Slab oject wrapper from a gdb.Value object of struct list_head type.

abstract classmethod from_page(page: Page) → Slab

Create Slab object wrapper from a Page struct page wrapper.

abstract get_allocated_objects() → Iterable[int]

Generates object addresses for all allocated objects in the slab.

abstract long_header() → str

Return a long header consisting of slab’s address, role and stats.

abstract obj_in_use(addr: int) → Tuple[bool, str | None]

Returns information about whether object is allocated (in use) or free.

Arg:

addr: Base address of object to check, obtained e.g. by find.obj()

Returns:

obj:(in_use, free_details): A tuple with information. in_use (:obj:`bool): Whether object is currently in use. free_details (str): If an object is in some special cache

of free objects (e.g. per-cpu), a short description of such cache.

populate_free() → None

Make sure the set of free objects is populated

abstract print_objects() → None

Print all objects in slab, indicating if they are free or allocated.

abstract short_header() → str

Return a short header consisting of slab’s address and role.

class crash.types.slab.SlabSLAB(gdb_obj: Value, kmem_cache: KmemCacheSLAB, error: bool = False)

Bases: Slab

AC_ALIEN = 'alien'

AC_PERCPU = 'percpu'

AC_SHARED = 'shared'

BUFCTL_END = 4294967295

bufctl_type: Type

check(slabtype: int, nid: int) → int

classmethod check_bufctl_type(gdbtype: Type) → None

classmethod check_page_type(gdbtype: Type) → None

classmethod check_slab_type(gdbtype: Type) → None

contains_obj(addr: int) → Tuple[bool, int, str | None]

Returns whether the slab contains an object at given address.

Parameters:

addr – Address of object to check.

Returns:

A tuple with object information. contains (bool): Whether addr points inside valid object

range.

address (int): Starting address of the object. Might be

returned even if contains is False, when addr falls e.g. into a red zone or padding of an object.

description (str): Optional description of where addr points

to in case it’s not a valid object.

Return type:

(contains, address, description)

find_obj(addr: int) → int | None

Returns starting address of object in slab.

Parameters:

addr – Address of the object to find.

Returns:

Starting address of the object, or None if the address

does not fall into the slab’s range. Note that while object address might be returned, addr might still be outside of valid range. Use contains_obj() to verify.

Return type:

int

classmethod from_addr(slab_addr: int, kmem_cache: int | KmemCacheSLAB) → SlabSLAB

classmethod from_list_head(list_head: Value, kmem_cache: KmemCache) → SlabSLAB

Create Slab oject wrapper from a gdb.Value object of struct list_head type.

classmethod from_page(page: Page) → SlabSLAB

Create Slab object wrapper from a Page struct page wrapper.

get_allocated_objects() → Iterable[int]

Generates object addresses for all allocated objects in the slab.

get_objects() → Iterable[int]

kmem_cache: KmemCacheSLAB

long_header() → str

Return a long header consisting of slab’s address, role and stats.

obj_in_use(addr: int) → Tuple[bool, str | None]

Returns information about whether object is allocated (in use) or free.

Arg:

addr: Base address of object to check, obtained e.g. by find.obj()

Returns:

obj:(in_use, free_details): A tuple with information. in_use (:obj:`bool): Whether object is currently in use. free_details (str): If an object is in some special cache

of free objects (e.g. per-cpu), a short description of such cache.

page_slab: bool = False

print_objects() → None

Print all objects in slab, indicating if they are free or allocated.

real_slab_type: Type

short_header() → str

Return a short header consisting of slab’s address and role.

slab_free = 2

slab_full = 1

slab_list_head: str = 'list'

slab_partial = 0

class crash.types.slab.SlabSLUB(gdb_obj: Value, kmem_cache: KmemCacheSLUB)

Bases: Slab

contains_obj(addr: int) → Tuple[bool, int, str | None]

Returns whether the slab contains an object at given address.

Parameters:

addr – Address of object to check.

Returns:

A tuple with object information. contains (bool): Whether addr points inside valid object

range.

address (int): Starting address of the object. Might be

returned even if contains is False, when addr falls e.g. into a red zone or padding of an object.

description (str): Optional description of where addr points

to in case it’s not a valid object.

Return type:

(contains, address, description)

find_obj(addr: int) → int | None

Returns starting address of object in slab.

Parameters:

addr – Address of the object to find.

Returns:

Starting address of the object, or None if the address

does not fall into the slab’s range. Note that while object address might be returned, addr might still be outside of valid range. Use contains_obj() to verify.

Return type:

int

classmethod from_list_head(list_head: Value, kmem_cache: KmemCache) → SlabSLUB

Create Slab oject wrapper from a gdb.Value object of struct list_head type.

classmethod from_page(page: Page) → SlabSLUB

Create Slab object wrapper from a Page struct page wrapper.

classmethod from_page_obj(page: Value) → SlabSLUB

get_allocated_objects() → Iterable[int]

Generates object addresses for all allocated objects in the slab.

get_objects() → Iterable[int]

kmem_cache: KmemCacheSLUB

long_header() → str

Return a long header consisting of slab’s address, role and stats.

obj_in_use(addr: int) → Tuple[bool, str | None]

Returns information about whether object is allocated (in use) or free.

Arg:

addr: Base address of object to check, obtained e.g. by find.obj()

Returns:

obj:(in_use, free_details): A tuple with information. in_use (:obj:`bool): Whether object is currently in use. free_details (str): If an object is in some special cache

of free objects (e.g. per-cpu), a short description of such cache.

print_objects() → None

Print all objects in slab, indicating if they are free or allocated.

short_header() → str

Return a short header consisting of slab’s address and role.

slab_role() → str

warn_frozen(expected: int, header: str) → None

crash.types.slab.atomic_long_read(val: Value) → int

crash.types.slab.col_bold(msg: str) → str

crash.types.slab.col_error(msg: str) → str

crash.types.slab.kmem_cache_from_addr(addr: int) → KmemCache

crash.types.slab.kmem_cache_from_name(name: str) → KmemCache

crash.types.slab.kmem_cache_get_all() → ValuesView[KmemCache]

crash.types.slab.print_flags(val: int, names: Dict[str, int]) → str

crash.types.slab.slab_from_obj_addr(addr: int) → Slab | None

crash.types.slab.slab_from_page(page: Page) → Slab