linux.git/include/linux/types.h, branch v7.3-rc2

Merge tag 'slab-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

2026-08-24T17:58:57+00:00

Pull slab updates from Vlastimil Babka:

 - Add kfree_rcu_nolock() that can be used from contexts where spinning
   on a lock might be unsafe, such as a BPF program attached to an
   arbitrary function, or in NMI context. This complements the existing
   kfree_nolock() support (Harry Yoo)

 - Runtime instead of compile-time slabobj_ext sizing.

   Avoid wasting memory when memory allocation profiling is compiled but
   not enabled, with initial partial support to also avoid wasting
   memory for objcg pointers when those are not needed, while profiling
   is enabled (Vlastimil Babka)

 - Various non-urgent fixes, cleanups and optimizations (Hao Li,
   Hongling Zeng, Li RongQing, Li Xiasong, Seongjun Hong, Shengming Hu)

* tag 'slab-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (31 commits)
  mm/slab, kfence, memcg: completely remove obj_ext for kfence objects
  mm/slab: stop allocating objcg pointers when unnecessary
  mm/slab: add cache_ and slab_needs_objcg() helpers
  mm/slab: stop exporting kvfree_rcu_barrier[_on_cache]()
  slub_kunit: extend the test for kfree_rcu_nolock()
  mm/slab: introduce kfree_rcu_nolock()
  mm/slab: introduce struct kvfree_rcu_head for kvfree_rcu batching
  mm/slab: reduce slabobj_ext memory with allocation profiling disabled
  mm/slab: introduce slab_obj_ext_has_codetag()
  mm/slab: allow kfree_rcu_sheaf() on PREEMPT_RT
  mm/slab: extend deferred free mechanism to handle rcu sheaves
  mm/slab: use call_rcu() in unknown context if irqs are enabled
  mm/slab: handle the !allow_spin case in kfree_rcu_sheaf()
  mm/slab: change struct slabobj_ext to a union
  mm/slab: replace slab.stride with obj_exts_in_object
  mm/slab: abstract slabobj_ext.ref access
  mm/slab: abstract slabobj_ext.objcg access
  mm/slab: make slab_obj_ext() determine object index
  mm: move struct slabobj_ext to mm/slab.h
  mm/slab: remove objs_per_slab()
  ...

mm/slab: introduce struct kvfree_rcu_head for kvfree_rcu batching

2026-08-04T10:18:11+00:00

rcu_head is overkill for kvfree_rcu() because the callback
function is always either kfree(), vfree(), or free_large_kmalloc(),
and thus there is no need for a function pointer.

kvfree_rcu batching reuses the field to store the start address
of an object, however, this is not strictly needed because we can
calculate the start address in the slowpath. For the purpose of
kvfree_rcu batching, it is sufficient to implement a linked list using
a single pointer.

Introduce a new struct called kvfree_rcu_head (the name was suggested
by Vlastimil Babka), which is similar to rcu_head but is only a single
pointer to build a linked list, without a function pointer, when
CONFIG_KVFREE_RCU_BATCHED=y.

When kvfree_rcu is not batched, kvfree_rcu_head is the same size
as rcu_head. Note that shrinking struct kvfree_rcu_head on
CONFIG_KVFREE_RCU_BATCHED=n kernels would inevitably require additional
complexity and also some sort of batching (which defeats the purpose of
the config option) because it cannot fall back to call_rcu().

For now there are no user-visible changes to the API. k[v]free_rcu()
simply casts rcu_head to kvfree_rcu_head. While this does not affect
the API, it allows kfree_rcu_nolock() to reuse kvfree_rcu batching
as a fallback when trylock or sheaf allocation fails.

Stop storing the object pointer in rcu_head.func and instead calculate
the object's start address in kvfree_rcu_list(). Factor out the existing
logic to calculate the start address from kvfree_rcu_cb() to
kvmalloc_obj_start_addr(). To avoid losing the KASAN tag, calculate
the offset and subtract it from the address of the kvfree_rcu_head.

Signed-off-by: Harry Yoo (Oracle) 
Link: https://patch.msgid.link/20260729-kfree_rcu_nolock-v5-6-a28cdcda9673@kernel.org
Signed-off-by: Vlastimil Babka (SUSE)

fs, block: move blk_mode_t and fop_flags_t into

2026-06-29T08:31:51+00:00

blk_mode_t and fop_flags_t are both plain 'unsigned int __bitwise' flag
typedefs, exactly like the gfp_t, slab_flags_t and fmode_t that already
live in . Move them there so they are available
everywhere without having to drag in a subsystem header.

Reviewed-by: Jan Kara 
Link: https://patch.msgid.link/20260616-work-super-bdev_holder_global-v2-4-7df6b864028e@kernel.org
Tested-by: syzbot@syzkaller.appspotmail.com
Signed-off-by: Christian Brauner (Amutable)

kcov: refactor common handle ID into kcov_common_handle_id

2026-05-29T04:24:45+00:00

Store common handle IDs in "struct kcov_common_handle_id", which consumes
no space in non-KCOV builds.

This cleanup removes #ifdef boilerplate code from subsystems that
integrate with KCOV (in particular in usbip_common.h and skbuff.h, see the
diffstat).

This should also make it easier to add KCOV remote coverage to more
subsystems in the future.

Link: https://lore.kernel.org/20260430-kcov-refactor-common-handle-v1-1-23a0c7a0ba38@google.com
Signed-off-by: Jann Horn 
Acked-by: Greg Kroah-Hartman 
Reviewed-by: Dmitry Vyukov 
Acked-by: Jakub Kicinski 
Cc: Alexander Potapenko 
Cc: Andrey Konovalov 
Cc: Eugenio Pérez 
Cc: Hongren (Zenithal) Zheng 
Cc: Jann Horn 
Cc: Jason Wang 
Cc: "Michael S. Tsirkin" 
Cc: Shuah Khan 
Cc: Valentina Manea 
Signed-off-by: Andrew Morton

mm: rename the 'compound_head' field in the 'struct page' to 'compound_info'

2026-04-05T20:53:08+00:00

The 'compound_head' field in the 'struct page' encodes whether the page is
a tail and where to locate the head page.  Bit 0 is set if the page is a
tail, and the remaining bits in the field point to the head page.

As preparation for changing how the field encodes information about the
head page, rename the field to 'compound_info'.

Link: https://lkml.kernel.org/r/20260227194302.274384-4-kas@kernel.org
Signed-off-by: Kiryl Shutsemau 
Reviewed-by: Muchun Song 
Reviewed-by: Zi Yan 
Acked-by: David Hildenbrand (arm) 
Reviewed-by: Vlastimil Babka 
Cc: Albert Ou 
Cc: Alexandre Ghiti 
Cc: Baoquan He 
Cc: Christoph Lameter 
Cc: David Rientjes 
Cc: Frank van der Linden 
Cc: Harry Yoo 
Cc: Huacai Chen 
Cc: Johannes Weiner 
Cc: Jonathan Corbet 
Cc: Lorenzo Stoakes 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Oscar Salvador 
Cc: Palmer Dabbelt 
Cc: Paul Walmsley 
Cc: Roman Gushchin 
Cc: Usama Arif 
Cc: WANG Xuerui 
Signed-off-by: Andrew Morton

Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-02-12T20:13:01+00:00

Pull non-MM updates from Andrew Morton:

 - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
   disk space by teaching ocfs2 to reclaim suballocator block group
   space (Heming Zhao)

 - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
   ARRAY_END() macro and uses it in various places (Alejandro Colomar)

 - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
   the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
   page size (Pnina Feder)

 - "kallsyms: Prevent invalid access when showing module buildid" cleans
   up kallsyms code related to module buildid and fixes an invalid
   access crash when printing backtraces (Petr Mladek)

 - "Address page fault in ima_restore_measurement_list()" fixes a
   kexec-related crash that can occur when booting the second-stage
   kernel on x86 (Harshit Mogalapalli)

 - "kho: ABI headers and Documentation updates" updates the kexec
   handover ABI documentation (Mike Rapoport)

 - "Align atomic storage" adds the __aligned attribute to atomic_t and
   atomic64_t definitions to get natural alignment of both types on
   csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)

 - "kho: clean up page initialization logic" simplifies the page
   initialization logic in kho_restore_page() (Pratyush Yadav)

 - "Unload linux/kernel.h" moves several things out of kernel.h and into
   more appropriate places (Yury Norov)

 - "don't abuse task_struct.group_leader" removes the usage of
   ->group_leader when it is "obviously unnecessary" (Oleg Nesterov)

 - "list private v2 & luo flb" adds some infrastructure improvements to
   the live update orchestrator (Pasha Tatashin)

* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
  watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
  procfs: fix missing RCU protection when reading real_parent in do_task_stat()
  watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
  kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
  kho: fix doc for kho_restore_pages()
  tests/liveupdate: add in-kernel liveupdate test
  liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
  liveupdate: luo_file: Use private list
  list: add kunit test for private list primitives
  list: add primitives for private list manipulations
  delayacct: fix uapi timespec64 definition
  panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
  netclassid: use thread_group_leader(p) in update_classid_task()
  RDMA/umem: don't abuse current->group_leader
  drm/pan*: don't abuse current->group_leader
  drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
  drm/amdgpu: don't abuse current->group_leader
  android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
  android/binder: don't abuse current->group_leader
  kho: skip memoryless NUMA nodes when reserving scratch areas
  ...

atomic: specify alignment for atomic_t and atomic64_t

2026-01-27T03:07:14+00:00

Some recent commits incorrectly assumed 4-byte alignment of locks.  That
assumption fails on Linux/m68k (and, interestingly, would have failed on
Linux/cris also).  The jump label implementation makes a similar alignment
assumption.

The expectation that atomic_t and atomic64_t variables will be naturally
aligned seems reasonable, as indeed they are on 64-bit architectures.  But
atomic64_t isn't naturally aligned on csky, m68k, microblaze, nios2,
openrisc and sh.  Neither atomic_t nor atomic64_t are naturally aligned on
m68k.

This patch brings a little uniformity by specifying natural alignment for
atomic types.  One benefit is that atomic64_t variables do not get split
across a page boundary.  The cost is that some structs grow which leads to
cache misses and wasted memory.

See also, commit bbf2a330d92c ("x86: atomic64: The atomic64_t data type
should be 8 bytes aligned on 32-bit too").

Link: https://lkml.kernel.org/r/a76bc24a4e7c1d8112d7d5fa8d14e4b694a0e90c.1768281748.git.fthain@linux-m68k.org
Link: https://lore.kernel.org/lkml/CAFr9PX=MYUDGJS2kAvPMkkfvH+0-SwQB_kxE4ea0J_wZ_pk=7w@mail.gmail.com
Link: https://lore.kernel.org/lkml/CAMuHMdW7Ab13DdGs2acMQcix5ObJK0O2dG_Fxzr8_g58Rc1_0g@mail.gmail.com/
Signed-off-by: Finn Thain 
Acked-by: Guo Ren 
Reviewed-by: Arnd Bergmann 
Cc: Guo Ren 
Cc: Geert Uytterhoeven 
Cc: Dinh Nguyen 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: Stafford Horne 
Cc: Yoshinori Sato 
Cc: Rich Felker 
Cc: John Paul Adrian Glaubitz 
Cc: Alexei Starovoitov 
Cc: Andrii Nakryiko 
Cc: Ard Biesheuvel 
Cc: Boqun Feng 
Cc: "Borislav Petkov (AMD)" 
Cc: Daniel Borkman 
Cc: Dave Hansen 
Cc: Eduard Zingerman 
Cc: Gary Guo 
Cc: Hao Luo 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: John Fastabend 
Cc: KP Singh 
Cc: Marc Rutland 
Cc: Martin KaFai Lau 
Cc: Peter Zijlstra 
Cc: Sasha Levin (Microsoft) 
Cc: Song Liu 
Cc: Stanislav Fomichev 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: Yonghong Song 
Signed-off-by: Andrew Morton

types: drop definition of __EXPORTED_HEADERS__

2026-01-27T03:07:10+00:00

This definition disarms the warning in uapi/linux/types.h about including
kernel headers from user space.  However the warning is already disarmed
due to the fact that kernel code is built with -D__KERNEL__.

Drop the pointless definition.

Link: https://lkml.kernel.org/r/20251230-exported-headers-types-h-v1-1-947fc606f3d8@linutronix.de
Signed-off-by: Thomas Weißschuh 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton

types: move phys_vec definition to common header

2026-01-06T12:47:54+00:00

Move the struct phys_vec definition from block/blk-mq-dma.c to
include/linux/types.h to make it available for use across the kernel.

The phys_vec structure represents a physical address range with a
length, which is used by the new physical address-based DMA mapping
API. This structure is already used by the block layer and will be
needed for DMA phys API users.

Moving this definition to types.h provides a centralized location
for this common data structure and eliminates code duplication
across subsystems that need to work with physical address ranges.

Signed-off-by: Leon Romanovsky 
Reviewed-by: Chaitanya Kulkarni 
Signed-off-by: Jens Axboe

fs: Add uoff_t

2025-11-25T09:07:42+00:00

In a recent commit, I inadvertently changed a comparison from being an
unsigned comparison (on 64-bit systems) to being a signed comparison
(which it had always been on 32-bit systems).  This led to a sporadic
fstests failure.

To make sure this comparison is always unsigned, introduce a new type,
uoff_t which is the unsigned version of loff_t.  Generally file sizes
are restricted to being a signed integer, but in these two places it is
convenient to pass -1 to indicate "up to the end of the file".

Signed-off-by: Matthew Wilcox (Oracle) 
Link: https://patch.msgid.link/20251123220518.1447261-1-willy@infradead.org
Signed-off-by: Christian Brauner