<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/lib/Kconfig.debug, branch v7.1-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux</title>
<updated>2026-04-24T17:00:37+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-24T17:00:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=feff82eb5f4075d541990d0ba60dad14ea83ea9b'/>
<id>feff82eb5f4075d541990d0ba60dad14ea83ea9b</id>
<content type='text'>
Pull RISC-V updates from Paul Walmsley:
 "There is one significant change outside arch/riscv in this pull
  request: the addition of a set of KUnit tests for strlen(), strnlen(),
  and strrchr().

  Otherwise, the most notable changes are to add some RISC-V-specific
  string function implementations, to remove XIP kernel support, to add
  hardware error exception handling, and to optimize our runtime
  unaligned access speed testing.

  A few comments on the motivation for removing XIP support. It's been
  broken in the RISC-V kernel for months. The code is not easy to
  maintain. Furthermore, for XIP support to truly be useful for RISC-V,
  we think that compile-time feature switches would need to be added for
  many of the RISC-V ISA features and microarchitectural properties that
  are currently implemented with runtime patching. No one has stepped
  forward to take responsibility for that work, so many of us think it's
  best to remove it until clear use cases and champions emerge.

  Summary:

   - Add Kunit correctness testing and microbenchmarks for strlen(),
     strnlen(), and strrchr()

   - Add RISC-V-specific strnlen(), strchr(), strrchr() implementations

   - Add hardware error exception handling

   - Clean up and optimize our unaligned access probe code

   - Enable HAVE_IOREMAP_PROT to be able to use generic_access_phys()

   - Remove XIP kernel support

   - Warn when addresses outside the vmemmap range are passed to
     vmemmap_populate()

   - Update the ACPI FADT revision check to warn if it's not at least
     ACPI v6.6, which is when key RISC-V-specific tables were added to
     the specification

   - Increase COMMAND_LINE_SIZE to 2048 to match ARM64, x86, PowerPC,
     etc.

   - Make kaslr_offset() a static inline function, since there's no need
     for it to show up in the symbol table

   - Add KASLR offset and SATP to the VMCOREINFO ELF notes to improve
     kdump support

   - Add Makefile cleanup rule for vdso_cfi copied source files, and add
     a .gitignore for the build artifacts in that directory

   - Remove some redundant ifdefs that check Kconfig macros

   - Add missing SPDX license tag to the CFI selftest

   - Simplify UTS_MACHINE assignment in the RISC-V Makefile

   - Clarify some unclear comments and remove some superfluous comments

   - Fix various English typos across the RISC-V codebase"

* tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits)
  riscv: Remove support for XIP kernel
  riscv: Reuse compare_unaligned_access() in check_vector_unaligned_access()
  riscv: Split out compare_unaligned_access()
  riscv: Reuse measure_cycles() in check_vector_unaligned_access()
  riscv: Split out measure_cycles() for reuse
  riscv: Clean up &amp; optimize unaligned scalar access probe
  riscv: lib: add strrchr() implementation
  riscv: lib: add strchr() implementation
  riscv: lib: add strnlen() implementation
  lib/string_kunit: extend benchmarks to strnlen() and chr searches
  lib/string_kunit: add performance benchmark for strlen()
  lib/string_kunit: add correctness test for strrchr()
  lib/string_kunit: add correctness test for strnlen()
  lib/string_kunit: add correctness test for strlen()
  riscv: vdso_cfi: Add .gitignore for build artifacts
  riscv: vdso_cfi: Add clean rule for copied sources
  riscv: enable HAVE_IOREMAP_PROT
  riscv: mm: WARN_ON() for bad addresses in vmemmap_populate()
  riscv: acpi: update FADT revision check to 6.6
  riscv: add hardware error trap handler support
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull RISC-V updates from Paul Walmsley:
 "There is one significant change outside arch/riscv in this pull
  request: the addition of a set of KUnit tests for strlen(), strnlen(),
  and strrchr().

  Otherwise, the most notable changes are to add some RISC-V-specific
  string function implementations, to remove XIP kernel support, to add
  hardware error exception handling, and to optimize our runtime
  unaligned access speed testing.

  A few comments on the motivation for removing XIP support. It's been
  broken in the RISC-V kernel for months. The code is not easy to
  maintain. Furthermore, for XIP support to truly be useful for RISC-V,
  we think that compile-time feature switches would need to be added for
  many of the RISC-V ISA features and microarchitectural properties that
  are currently implemented with runtime patching. No one has stepped
  forward to take responsibility for that work, so many of us think it's
  best to remove it until clear use cases and champions emerge.

  Summary:

   - Add Kunit correctness testing and microbenchmarks for strlen(),
     strnlen(), and strrchr()

   - Add RISC-V-specific strnlen(), strchr(), strrchr() implementations

   - Add hardware error exception handling

   - Clean up and optimize our unaligned access probe code

   - Enable HAVE_IOREMAP_PROT to be able to use generic_access_phys()

   - Remove XIP kernel support

   - Warn when addresses outside the vmemmap range are passed to
     vmemmap_populate()

   - Update the ACPI FADT revision check to warn if it's not at least
     ACPI v6.6, which is when key RISC-V-specific tables were added to
     the specification

   - Increase COMMAND_LINE_SIZE to 2048 to match ARM64, x86, PowerPC,
     etc.

   - Make kaslr_offset() a static inline function, since there's no need
     for it to show up in the symbol table

   - Add KASLR offset and SATP to the VMCOREINFO ELF notes to improve
     kdump support

   - Add Makefile cleanup rule for vdso_cfi copied source files, and add
     a .gitignore for the build artifacts in that directory

   - Remove some redundant ifdefs that check Kconfig macros

   - Add missing SPDX license tag to the CFI selftest

   - Simplify UTS_MACHINE assignment in the RISC-V Makefile

   - Clarify some unclear comments and remove some superfluous comments

   - Fix various English typos across the RISC-V codebase"

* tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits)
  riscv: Remove support for XIP kernel
  riscv: Reuse compare_unaligned_access() in check_vector_unaligned_access()
  riscv: Split out compare_unaligned_access()
  riscv: Reuse measure_cycles() in check_vector_unaligned_access()
  riscv: Split out measure_cycles() for reuse
  riscv: Clean up &amp; optimize unaligned scalar access probe
  riscv: lib: add strrchr() implementation
  riscv: lib: add strchr() implementation
  riscv: lib: add strnlen() implementation
  lib/string_kunit: extend benchmarks to strnlen() and chr searches
  lib/string_kunit: add performance benchmark for strlen()
  lib/string_kunit: add correctness test for strrchr()
  lib/string_kunit: add correctness test for strnlen()
  lib/string_kunit: add correctness test for strlen()
  riscv: vdso_cfi: Add .gitignore for build artifacts
  riscv: vdso_cfi: Add clean rule for copied sources
  riscv: enable HAVE_IOREMAP_PROT
  riscv: mm: WARN_ON() for bad addresses in vmemmap_populate()
  riscv: acpi: update FADT revision check to 6.6
  riscv: add hardware error trap handler support
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq</title>
<updated>2026-04-15T17:32:08+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-15T17:32:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7de6b4a246330fe29fa2fd144b4724ca35d60d6c'/>
<id>7de6b4a246330fe29fa2fd144b4724ca35d60d6c</id>
<content type='text'>
Pull workqueue updates from Tejun Heo:

 - New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
   smaller shards to improve scalability on machines with many CPUs per
   LLC

 - Misc:
    - system_dfl_long_wq for long unbound works
    - devm_alloc_workqueue() for device-managed allocation
    - sysfs exposure for ordered workqueues and the EFI workqueue
    - removal of HK_TYPE_WQ from wq_unbound_cpumask
    - various small fixes

* tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (21 commits)
  workqueue: validate cpumask_first() result in llc_populate_cpu_shard_id()
  workqueue: use NR_STD_WORKER_POOLS instead of hardcoded value
  workqueue: avoid unguarded 64-bit division
  docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: add test_workqueue benchmark module
  tools/workqueue: add CACHE_SHARD support to wq_dump.py
  workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope
  workqueue: add WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: fix typo in WQ_AFFN_SMT comment
  workqueue: Remove HK_TYPE_WQ from affecting wq_unbound_cpumask
  workqueue: unlink pwqs from wq-&gt;pwqs list in alloc_and_link_pwqs() error path
  workqueue: Remove NULL wq WARN in __queue_delayed_work()
  workqueue: fix parse_affn_scope() prefix matching bug
  workqueue: devres: Add device-managed allocate workqueue
  workqueue: Add system_dfl_long_wq for long unbound works
  tools/workqueue/wq_dump.py: add NODE prefix to all node columns
  tools/workqueue/wq_dump.py: fix column alignment in node_nr/max_active section
  tools/workqueue/wq_dump.py: remove backslash separator from node_nr/max_active header
  efi: Allow to expose the workqueue via sysfs
  workqueue: Allow to expose ordered workqueues via sysfs
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull workqueue updates from Tejun Heo:

 - New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
   smaller shards to improve scalability on machines with many CPUs per
   LLC

 - Misc:
    - system_dfl_long_wq for long unbound works
    - devm_alloc_workqueue() for device-managed allocation
    - sysfs exposure for ordered workqueues and the EFI workqueue
    - removal of HK_TYPE_WQ from wq_unbound_cpumask
    - various small fixes

* tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (21 commits)
  workqueue: validate cpumask_first() result in llc_populate_cpu_shard_id()
  workqueue: use NR_STD_WORKER_POOLS instead of hardcoded value
  workqueue: avoid unguarded 64-bit division
  docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: add test_workqueue benchmark module
  tools/workqueue: add CACHE_SHARD support to wq_dump.py
  workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope
  workqueue: add WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: fix typo in WQ_AFFN_SMT comment
  workqueue: Remove HK_TYPE_WQ from affecting wq_unbound_cpumask
  workqueue: unlink pwqs from wq-&gt;pwqs list in alloc_and_link_pwqs() error path
  workqueue: Remove NULL wq WARN in __queue_delayed_work()
  workqueue: fix parse_affn_scope() prefix matching bug
  workqueue: devres: Add device-managed allocate workqueue
  workqueue: Add system_dfl_long_wq for long unbound works
  tools/workqueue/wq_dump.py: add NODE prefix to all node columns
  tools/workqueue/wq_dump.py: fix column alignment in node_nr/max_active section
  tools/workqueue/wq_dump.py: remove backslash separator from node_nr/max_active header
  efi: Allow to expose the workqueue via sysfs
  workqueue: Allow to expose ordered workqueues via sysfs
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2026-04-14T19:36:25+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-14T19:36:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7393febcb1b2082c0484952729cbebfe4dc508d5'/>
<id>7393febcb1b2082c0484952729cbebfe4dc508d5</id>
<content type='text'>
Pull locking updates from Ingo Molnar:
 "Mutexes:

   - Add killable flavor to guard definitions (Davidlohr Bueso)

   - Remove the list_head from struct mutex (Matthew Wilcox)

   - Rename mutex_init_lockep() (Davidlohr Bueso)

  rwsems:

   - Remove the list_head from struct rw_semaphore and
     replace it with a single pointer (Matthew Wilcox)

   - Fix logic error in rwsem_del_waiter() (Andrei Vagin)

  Semaphores:

   - Remove the list_head from struct semaphore (Matthew Wilcox)

  Jump labels:

   - Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh)

   - Remove workaround for old compilers in initializations
     (Thomas Weißschuh)

  Lock context analysis changes and improvements:

   - Add context analysis for rwsems (Peter Zijlstra)

   - Fix rwlock and spinlock lock context annotations (Bart Van Assche)

   - Fix rwlock support in &lt;linux/spinlock_up.h&gt; (Bart Van Assche)

   - Add lock context annotations in the spinlock implementation
     (Bart Van Assche)

   - signal: Fix the lock_task_sighand() annotation (Bart Van Assche)

   - ww-mutex: Fix the ww_acquire_ctx function annotations
     (Bart Van Assche)

   - Add lock context support in do_raw_{read,write}_trylock()
     (Bart Van Assche)

   - arm64, compiler-context-analysis: Permit alias analysis through
     __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

   - Add __cond_releases() (Peter Zijlstra)

   - Add context analysis for mutexes (Peter Zijlstra)

   - Add context analysis for rtmutexes (Peter Zijlstra)

   - Convert futexes to compiler context analysis (Peter Zijlstra)

  Rust integration updates:

   - Add atomic fetch_sub() implementation (Andreas Hindborg)

   - Refactor various rust_helper_ methods for expansion (Boqun Feng)

   - Add Atomic&lt;*{mut,const} T&gt; support (Boqun Feng)

   - Add atomic operation helpers over raw pointers (Boqun Feng)

   - Add performance-optimal Flag type for atomic booleans, to avoid
     slow byte-sized RMWs on architectures that don't support them.
     (FUJITA Tomonori)

   - Misc cleanups and fixes (Andreas Hindborg, Boqun Feng, FUJITA
     Tomonori)

  LTO support updates:

   - arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

   - compiler: Simplify generic RELOC_HIDE() (Marco Elver)

  Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap,
  Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov"

* tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  compiler: Simplify generic RELOC_HIDE()
  locking: Add lock context annotations in the spinlock implementation
  locking: Add lock context support in do_raw_{read,write}_trylock()
  locking: Fix rwlock support in &lt;linux/spinlock_up.h&gt;
  lockdep: Raise default stack trace limits when KASAN is enabled
  cleanup: Optimize guards
  jump_label: remove workaround for old compilers in initializations
  jump_label: use ATOMIC_INIT() for initialization of .enabled
  futex: Convert to compiler context analysis
  locking/rwsem: Fix logic error in rwsem_del_waiter()
  locking/rwsem: Add context analysis
  locking/rtmutex: Add context analysis
  locking/mutex: Add context analysis
  compiler-context-analysys: Add __cond_releases()
  locking/mutex: Remove the list_head from struct mutex
  locking/semaphore: Remove the list_head from struct semaphore
  locking/rwsem: Remove the list_head from struct rw_semaphore
  rust: atomic: Update a safety comment in impl of `fetch_add()`
  rust: sync: atomic: Update documentation for `fetch_add()`
  rust: sync: atomic: Add fetch_sub()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull locking updates from Ingo Molnar:
 "Mutexes:

   - Add killable flavor to guard definitions (Davidlohr Bueso)

   - Remove the list_head from struct mutex (Matthew Wilcox)

   - Rename mutex_init_lockep() (Davidlohr Bueso)

  rwsems:

   - Remove the list_head from struct rw_semaphore and
     replace it with a single pointer (Matthew Wilcox)

   - Fix logic error in rwsem_del_waiter() (Andrei Vagin)

  Semaphores:

   - Remove the list_head from struct semaphore (Matthew Wilcox)

  Jump labels:

   - Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh)

   - Remove workaround for old compilers in initializations
     (Thomas Weißschuh)

  Lock context analysis changes and improvements:

   - Add context analysis for rwsems (Peter Zijlstra)

   - Fix rwlock and spinlock lock context annotations (Bart Van Assche)

   - Fix rwlock support in &lt;linux/spinlock_up.h&gt; (Bart Van Assche)

   - Add lock context annotations in the spinlock implementation
     (Bart Van Assche)

   - signal: Fix the lock_task_sighand() annotation (Bart Van Assche)

   - ww-mutex: Fix the ww_acquire_ctx function annotations
     (Bart Van Assche)

   - Add lock context support in do_raw_{read,write}_trylock()
     (Bart Van Assche)

   - arm64, compiler-context-analysis: Permit alias analysis through
     __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

   - Add __cond_releases() (Peter Zijlstra)

   - Add context analysis for mutexes (Peter Zijlstra)

   - Add context analysis for rtmutexes (Peter Zijlstra)

   - Convert futexes to compiler context analysis (Peter Zijlstra)

  Rust integration updates:

   - Add atomic fetch_sub() implementation (Andreas Hindborg)

   - Refactor various rust_helper_ methods for expansion (Boqun Feng)

   - Add Atomic&lt;*{mut,const} T&gt; support (Boqun Feng)

   - Add atomic operation helpers over raw pointers (Boqun Feng)

   - Add performance-optimal Flag type for atomic booleans, to avoid
     slow byte-sized RMWs on architectures that don't support them.
     (FUJITA Tomonori)

   - Misc cleanups and fixes (Andreas Hindborg, Boqun Feng, FUJITA
     Tomonori)

  LTO support updates:

   - arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

   - compiler: Simplify generic RELOC_HIDE() (Marco Elver)

  Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap,
  Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov"

* tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  compiler: Simplify generic RELOC_HIDE()
  locking: Add lock context annotations in the spinlock implementation
  locking: Add lock context support in do_raw_{read,write}_trylock()
  locking: Fix rwlock support in &lt;linux/spinlock_up.h&gt;
  lockdep: Raise default stack trace limits when KASAN is enabled
  cleanup: Optimize guards
  jump_label: remove workaround for old compilers in initializations
  jump_label: use ATOMIC_INIT() for initialization of .enabled
  futex: Convert to compiler context analysis
  locking/rwsem: Fix logic error in rwsem_del_waiter()
  locking/rwsem: Add context analysis
  locking/rtmutex: Add context analysis
  locking/mutex: Add context analysis
  compiler-context-analysys: Add __cond_releases()
  locking/mutex: Remove the list_head from struct mutex
  locking/semaphore: Remove the list_head from struct semaphore
  locking/rwsem: Remove the list_head from struct rw_semaphore
  rust: atomic: Update a safety comment in impl of `fetch_add()`
  rust: sync: atomic: Update documentation for `fetch_add()`
  rust: sync: atomic: Add fetch_sub()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux</title>
<updated>2026-04-14T00:31:39+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-04-14T00:31:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=370c3883195566ee3e7d79e0146c3d735a406573'/>
<id>370c3883195566ee3e7d79e0146c3d735a406573</id>
<content type='text'>
Pull crypto library updates from Eric Biggers:

 - Migrate more hash algorithms from the traditional crypto subsystem to
   lib/crypto/

   Like the algorithms migrated earlier (e.g. SHA-*), this simplifies
   the implementations, improves performance, enables further
   simplifications in calling code, and solves various other issues:

     - AES CBC-based MACs (AES-CMAC, AES-XCBC-MAC, and AES-CBC-MAC)

         - Support these algorithms in lib/crypto/ using the AES library
           and the existing arm64 assembly code

         - Reimplement the traditional crypto API's "cmac(aes)",
           "xcbc(aes)", and "cbcmac(aes)" on top of the library

         - Convert mac80211 to use the AES-CMAC library. Note: several
           other subsystems can use it too and will be converted later

         - Drop the broken, nonstandard, and likely unused support for
           "xcbc(aes)" with key lengths other than 128 bits

         - Enable optimizations by default

     - GHASH

         - Migrate the standalone GHASH code into lib/crypto/

         - Integrate the GHASH code more closely with the very similar
           POLYVAL code, and improve the generic GHASH implementation to
           resist cache-timing attacks and use much less memory

         - Reimplement the AES-GCM library and the "gcm" crypto_aead
           template on top of the GHASH library. Remove "ghash" from the
           crypto_shash API, as it's no longer needed

         - Enable optimizations by default

     - SM3

         - Migrate the kernel's existing SM3 code into lib/crypto/, and
           reimplement the traditional crypto API's "sm3" on top of it

         - I don't recommend using SM3, but this cleanup is worthwhile
           to organize the code the same way as other algorithms

 - Testing improvements:

     - Add a KUnit test suite for each of the new library APIs

     - Migrate the existing ChaCha20Poly1305 test to KUnit

     - Make the KUnit all_tests.config enable all crypto library tests

     - Move the test kconfig options to the Runtime Testing menu

 - Other updates to arch-optimized crypto code:

     - Optimize SHA-256 for Zhaoxin CPUs using the Padlock Hash Engine

     - Remove some MD5 implementations that are no longer worth keeping

     - Drop big endian and voluntary preemption support from the arm64
       code, as those configurations are no longer supported on arm64

 - Make jitterentropy and samples/tsm-mr use the crypto library APIs

* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (66 commits)
  lib/crypto: arm64: Assume a little-endian kernel
  arm64: fpsimd: Remove obsolete cond_yield macro
  lib/crypto: arm64/sha3: Remove obsolete chunking logic
  lib/crypto: arm64/sha512: Remove obsolete chunking logic
  lib/crypto: arm64/sha256: Remove obsolete chunking logic
  lib/crypto: arm64/sha1: Remove obsolete chunking logic
  lib/crypto: arm64/poly1305: Remove obsolete chunking logic
  lib/crypto: arm64/gf128hash: Remove obsolete chunking logic
  lib/crypto: arm64/chacha: Remove obsolete chunking logic
  lib/crypto: arm64/aes: Remove obsolete chunking logic
  lib/crypto: Include &lt;crypto/utils.h&gt; instead of &lt;crypto/algapi.h&gt;
  lib/crypto: aesgcm: Don't disable IRQs during AES block encryption
  lib/crypto: aescfb: Don't disable IRQs during AES block encryption
  lib/crypto: tests: Migrate ChaCha20Poly1305 self-test to KUnit
  lib/crypto: sparc: Drop optimized MD5 code
  lib/crypto: mips: Drop optimized MD5 code
  lib: Move crypto library tests to Runtime Testing menu
  crypto: sm3 - Remove 'struct sm3_state'
  crypto: sm3 - Remove the original "sm3_block_generic()"
  crypto: sm3 - Remove sm3_base.h
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull crypto library updates from Eric Biggers:

 - Migrate more hash algorithms from the traditional crypto subsystem to
   lib/crypto/

   Like the algorithms migrated earlier (e.g. SHA-*), this simplifies
   the implementations, improves performance, enables further
   simplifications in calling code, and solves various other issues:

     - AES CBC-based MACs (AES-CMAC, AES-XCBC-MAC, and AES-CBC-MAC)

         - Support these algorithms in lib/crypto/ using the AES library
           and the existing arm64 assembly code

         - Reimplement the traditional crypto API's "cmac(aes)",
           "xcbc(aes)", and "cbcmac(aes)" on top of the library

         - Convert mac80211 to use the AES-CMAC library. Note: several
           other subsystems can use it too and will be converted later

         - Drop the broken, nonstandard, and likely unused support for
           "xcbc(aes)" with key lengths other than 128 bits

         - Enable optimizations by default

     - GHASH

         - Migrate the standalone GHASH code into lib/crypto/

         - Integrate the GHASH code more closely with the very similar
           POLYVAL code, and improve the generic GHASH implementation to
           resist cache-timing attacks and use much less memory

         - Reimplement the AES-GCM library and the "gcm" crypto_aead
           template on top of the GHASH library. Remove "ghash" from the
           crypto_shash API, as it's no longer needed

         - Enable optimizations by default

     - SM3

         - Migrate the kernel's existing SM3 code into lib/crypto/, and
           reimplement the traditional crypto API's "sm3" on top of it

         - I don't recommend using SM3, but this cleanup is worthwhile
           to organize the code the same way as other algorithms

 - Testing improvements:

     - Add a KUnit test suite for each of the new library APIs

     - Migrate the existing ChaCha20Poly1305 test to KUnit

     - Make the KUnit all_tests.config enable all crypto library tests

     - Move the test kconfig options to the Runtime Testing menu

 - Other updates to arch-optimized crypto code:

     - Optimize SHA-256 for Zhaoxin CPUs using the Padlock Hash Engine

     - Remove some MD5 implementations that are no longer worth keeping

     - Drop big endian and voluntary preemption support from the arm64
       code, as those configurations are no longer supported on arm64

 - Make jitterentropy and samples/tsm-mr use the crypto library APIs

* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (66 commits)
  lib/crypto: arm64: Assume a little-endian kernel
  arm64: fpsimd: Remove obsolete cond_yield macro
  lib/crypto: arm64/sha3: Remove obsolete chunking logic
  lib/crypto: arm64/sha512: Remove obsolete chunking logic
  lib/crypto: arm64/sha256: Remove obsolete chunking logic
  lib/crypto: arm64/sha1: Remove obsolete chunking logic
  lib/crypto: arm64/poly1305: Remove obsolete chunking logic
  lib/crypto: arm64/gf128hash: Remove obsolete chunking logic
  lib/crypto: arm64/chacha: Remove obsolete chunking logic
  lib/crypto: arm64/aes: Remove obsolete chunking logic
  lib/crypto: Include &lt;crypto/utils.h&gt; instead of &lt;crypto/algapi.h&gt;
  lib/crypto: aesgcm: Don't disable IRQs during AES block encryption
  lib/crypto: aescfb: Don't disable IRQs during AES block encryption
  lib/crypto: tests: Migrate ChaCha20Poly1305 self-test to KUnit
  lib/crypto: sparc: Drop optimized MD5 code
  lib/crypto: mips: Drop optimized MD5 code
  lib: Move crypto library tests to Runtime Testing menu
  crypto: sm3 - Remove 'struct sm3_state'
  crypto: sm3 - Remove the original "sm3_block_generic()"
  crypto: sm3 - Remove sm3_base.h
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/string_kunit: add performance benchmark for strlen()</title>
<updated>2026-04-05T00:42:44+00:00</updated>
<author>
<name>Feng Jiang</name>
<email>jiangfeng@kylinos.cn</email>
</author>
<published>2026-04-04T01:28:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0020240a431187628e2636284023e63b9b7a2aa1'/>
<id>0020240a431187628e2636284023e63b9b7a2aa1</id>
<content type='text'>
Introduce a benchmarking framework to the string_kunit test suite to
measure the execution efficiency of string functions.

The implementation is inspired by crc_benchmark(), measuring throughput
(MB/s) and latency (ns/call) across a range of string lengths. It
includes a warm-up phase, disables preemption during measurement, and
uses a fixed seed for reproducible results.

This framework allows for comparing different implementations (e.g.,
generic C vs. architecture-optimized assembly) within the KUnit
environment.

Initially, provide a benchmark for strlen().

Suggested-by: Andy Shevchenko &lt;andy@kernel.org&gt;
Suggested-by: Eric Biggers &lt;ebiggers@kernel.org&gt;
Signed-off-by: Feng Jiang &lt;jiangfeng@kylinos.cn&gt;
Reviewed-by: Kees Cook &lt;kees@kernel.org&gt;
Link: https://patch.msgid.link/20260130025018.172925-5-jiangfeng@kylinos.cn
[pjw@kernel.org: fixed a checkpatch issue]
Signed-off-by: Paul Walmsley &lt;pjw@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Introduce a benchmarking framework to the string_kunit test suite to
measure the execution efficiency of string functions.

The implementation is inspired by crc_benchmark(), measuring throughput
(MB/s) and latency (ns/call) across a range of string lengths. It
includes a warm-up phase, disables preemption during measurement, and
uses a fixed seed for reproducible results.

This framework allows for comparing different implementations (e.g.,
generic C vs. architecture-optimized assembly) within the KUnit
environment.

Initially, provide a benchmark for strlen().

Suggested-by: Andy Shevchenko &lt;andy@kernel.org&gt;
Suggested-by: Eric Biggers &lt;ebiggers@kernel.org&gt;
Signed-off-by: Feng Jiang &lt;jiangfeng@kylinos.cn&gt;
Reviewed-by: Kees Cook &lt;kees@kernel.org&gt;
Link: https://patch.msgid.link/20260130025018.172925-5-jiangfeng@kylinos.cn
[pjw@kernel.org: fixed a checkpatch issue]
Signed-off-by: Paul Walmsley &lt;pjw@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>workqueue: add test_workqueue benchmark module</title>
<updated>2026-04-01T20:24:18+00:00</updated>
<author>
<name>Breno Leitao</name>
<email>leitao@debian.org</email>
</author>
<published>2026-04-01T13:03:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=24b2e73f9700e0682575feb34556b756e59d4548'/>
<id>24b2e73f9700e0682575feb34556b756e59d4548</id>
<content type='text'>
Add a kernel module that benchmarks queue_work() throughput on an
unbound workqueue to measure pool-&gt;lock contention under different
affinity scope configurations (cache vs cache_shard).

The module spawns N kthreads (default: num_online_cpus()), each bound
to a different CPU. All threads start simultaneously and queue work
items, measuring the latency of each queue_work() call. Results are
reported as p50/p90/p95 latencies for each affinity scope.

The affinity scope is switched between runs via the workqueue's sysfs
affinity_scope attribute (WQ_SYSFS), avoiding the need for any new
exported symbols.

The module runs as __init-only, returning -EAGAIN to auto-unload,
and can be re-run via insmod.

Example of the output:

 running 50 threads, 50000 items/thread

   cpu              6806017 items/sec p50=2574    p90=5068    p95=5818 ns
   smt              6821040 items/sec p50=2624    p90=5168    p95=5949 ns
   cache_shard      1633653 items/sec p50=5337    p90=9694    p95=11207 ns
   cache            286069 items/sec p50=72509    p90=82304   p95=85009 ns
   numa             319403 items/sec p50=63745    p90=73480   p95=76505 ns
   system           308461 items/sec p50=66561    p90=75714   p95=78048 ns

Signed-off-by: Breno Leitao &lt;leitao@debian.org&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a kernel module that benchmarks queue_work() throughput on an
unbound workqueue to measure pool-&gt;lock contention under different
affinity scope configurations (cache vs cache_shard).

The module spawns N kthreads (default: num_online_cpus()), each bound
to a different CPU. All threads start simultaneously and queue work
items, measuring the latency of each queue_work() call. Results are
reported as p50/p90/p95 latencies for each affinity scope.

The affinity scope is switched between runs via the workqueue's sysfs
affinity_scope attribute (WQ_SYSFS), avoiding the need for any new
exported symbols.

The module runs as __init-only, returning -EAGAIN to auto-unload,
and can be re-run via insmod.

Example of the output:

 running 50 threads, 50000 items/thread

   cpu              6806017 items/sec p50=2574    p90=5068    p95=5818 ns
   smt              6821040 items/sec p50=2624    p90=5168    p95=5949 ns
   cache_shard      1633653 items/sec p50=5337    p90=9694    p95=11207 ns
   cache            286069 items/sec p50=72509    p90=82304   p95=85009 ns
   numa             319403 items/sec p50=63745    p90=73480   p95=76505 ns
   system           308461 items/sec p50=66561    p90=75714   p95=78048 ns

Signed-off-by: Breno Leitao &lt;leitao@debian.org&gt;
Signed-off-by: Tejun Heo &lt;tj@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>kbuild: rust: provide an option to inline C helpers into Rust</title>
<updated>2026-03-30T00:03:52+00:00</updated>
<author>
<name>Gary Guo</name>
<email>gary@garyguo.net</email>
</author>
<published>2026-02-03T11:34:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3a2486cc1da5cf637fe5da4540929d67c4540022'/>
<id>3a2486cc1da5cf637fe5da4540929d67c4540022</id>
<content type='text'>
A new experimental Kconfig option, `RUST_INLINE_HELPERS` is added to
allow C helpers (which were created to allow Rust to call into
inline/macro C functions without having to re-implement the logic in
Rust) to be inlined into Rust crates without performing global LTO.

If the option is enabled, the following is performed:
* For helpers, instead of compiling them to an object file to be linked
  into vmlinux, they're compiled to LLVM IR bitcode. Two versions are
  generated: one for built-in code (`helpers.bc`) and one for modules
  (`helpers_module.bc`, with -DMODULE defined). This ensures that C
  macros/inlines that behave differently for modules (e.g. static calls)
  function correctly when inlined.
* When a Rust crate or object is compiled, instead of generating an
  object file, LLVM bitcode is generated.
* llvm-link is invoked with --internalize to combine the helper bitcode
  with the crate bitcode. This step is similar to LTO, but this is much
  faster since it only needs to inline the helpers.
* clang is invoked to turn the combined bitcode into a final object file.
* Since clang may produce LLVM bitcode when LTO is enabled, and objtool
  requires ELF input, $(cmd_ld_single) is invoked to ensure the object
  is converted to ELF before objtool runs.

The --internalize flag tells llvm-link to treat all symbols in
helpers.bc using `internal` linkage [1]. This matches the behavior of
`clang` on `static inline` functions, and avoids exporting the symbol
from the object file.

To ensure that RUST_INLINE_HELPERS is not incompatible with BTF, we pass
the -g0 flag when building helpers. See commit 5daa0c35a1f0 ("rust:
Disallow BTF generation with Rust + LTO") for details.

We have an intended triple mismatch of `aarch64-unknown-none` vs
`aarch64-unknown-linux-gnu`, so we pass --suppress-warnings to llvm-link
to suppress it.

I considered adding some sort of check that KBUILD_MODNAME is not
present in helpers_module.bc, but this is actually not so easy to carry
out because .bc files store strings in a weird binary format, so you
cannot just grep it for a string to check whether it ended up using
KBUILD_MODNAME anywhere.

[ Andreas writes:

    For the rnull driver, enabling helper inlining with this patch
    gives an average speedup of 2% over the set of 120 workloads that
    we publish on [2].

    Link: https://rust-for-linux.com/null-block-driver [2]

  This series also uncovered a pre-existing UB instance thanks to an
  `objtool` warning which I noticed while testing the series (details
  in the mailing list).

      - Miguel ]

Link: https://github.com/llvm/llvm-project/pull/170397 [1]
Co-developed-by: Boqun Feng &lt;boqun.feng@gmail.com&gt;
Signed-off-by: Boqun Feng &lt;boqun.feng@gmail.com&gt;
Co-developed-by: Matthew Maurer &lt;mmaurer@google.com&gt;
Signed-off-by: Matthew Maurer &lt;mmaurer@google.com&gt;
Signed-off-by: Gary Guo &lt;gary@garyguo.net&gt;
Co-developed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Andreas Hindborg &lt;a.hindborg@kernel.org&gt;
Reviewed-by: Andreas Hindborg &lt;a.hindborg@kernel.org&gt;
Link: https://patch.msgid.link/20260203-inline-helpers-v2-3-beb8547a03c9@google.com
[ Some changes, apart from the rebase:

  - Added "(EXPERIMENTAL)" to Kconfig as the commit mentions.

  - Added `depends on ARM64 || X86_64` and `!UML` for now, since this is
    experimental, other architectures may require other changes (e.g.
    the issues I mentioned in the mailing list for ARM and UML) and they
    are not really tested so far. So let arch maintainers pick this up
    if they think it is worth it.

  - Gated the `cmd_ld_single` step also into the new mode, which also
    means that any possible future `objcopy` step is done after the
    translation, as expected.

  - Added `.gitignore` for `.bc` with exception for existing script.

  - Added `part-of-*` for helpers bitcode files as discussed, and
    dropped `$(if $(filter %_module.bc,$@),-DMODULE)` since `-DMODULE`
    is already there (would be duplicated otherwise).

  - Moved `LLVM_LINK` to keep binutils list alphabetized.

  - Fixed typo in title.

  - Dropped second `cmd_ld_single` commit message paragraph.

      - Miguel ]
Signed-off-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A new experimental Kconfig option, `RUST_INLINE_HELPERS` is added to
allow C helpers (which were created to allow Rust to call into
inline/macro C functions without having to re-implement the logic in
Rust) to be inlined into Rust crates without performing global LTO.

If the option is enabled, the following is performed:
* For helpers, instead of compiling them to an object file to be linked
  into vmlinux, they're compiled to LLVM IR bitcode. Two versions are
  generated: one for built-in code (`helpers.bc`) and one for modules
  (`helpers_module.bc`, with -DMODULE defined). This ensures that C
  macros/inlines that behave differently for modules (e.g. static calls)
  function correctly when inlined.
* When a Rust crate or object is compiled, instead of generating an
  object file, LLVM bitcode is generated.
* llvm-link is invoked with --internalize to combine the helper bitcode
  with the crate bitcode. This step is similar to LTO, but this is much
  faster since it only needs to inline the helpers.
* clang is invoked to turn the combined bitcode into a final object file.
* Since clang may produce LLVM bitcode when LTO is enabled, and objtool
  requires ELF input, $(cmd_ld_single) is invoked to ensure the object
  is converted to ELF before objtool runs.

The --internalize flag tells llvm-link to treat all symbols in
helpers.bc using `internal` linkage [1]. This matches the behavior of
`clang` on `static inline` functions, and avoids exporting the symbol
from the object file.

To ensure that RUST_INLINE_HELPERS is not incompatible with BTF, we pass
the -g0 flag when building helpers. See commit 5daa0c35a1f0 ("rust:
Disallow BTF generation with Rust + LTO") for details.

We have an intended triple mismatch of `aarch64-unknown-none` vs
`aarch64-unknown-linux-gnu`, so we pass --suppress-warnings to llvm-link
to suppress it.

I considered adding some sort of check that KBUILD_MODNAME is not
present in helpers_module.bc, but this is actually not so easy to carry
out because .bc files store strings in a weird binary format, so you
cannot just grep it for a string to check whether it ended up using
KBUILD_MODNAME anywhere.

[ Andreas writes:

    For the rnull driver, enabling helper inlining with this patch
    gives an average speedup of 2% over the set of 120 workloads that
    we publish on [2].

    Link: https://rust-for-linux.com/null-block-driver [2]

  This series also uncovered a pre-existing UB instance thanks to an
  `objtool` warning which I noticed while testing the series (details
  in the mailing list).

      - Miguel ]

Link: https://github.com/llvm/llvm-project/pull/170397 [1]
Co-developed-by: Boqun Feng &lt;boqun.feng@gmail.com&gt;
Signed-off-by: Boqun Feng &lt;boqun.feng@gmail.com&gt;
Co-developed-by: Matthew Maurer &lt;mmaurer@google.com&gt;
Signed-off-by: Matthew Maurer &lt;mmaurer@google.com&gt;
Signed-off-by: Gary Guo &lt;gary@garyguo.net&gt;
Co-developed-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Signed-off-by: Alice Ryhl &lt;aliceryhl@google.com&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Tested-by: Andreas Hindborg &lt;a.hindborg@kernel.org&gt;
Reviewed-by: Andreas Hindborg &lt;a.hindborg@kernel.org&gt;
Link: https://patch.msgid.link/20260203-inline-helpers-v2-3-beb8547a03c9@google.com
[ Some changes, apart from the rebase:

  - Added "(EXPERIMENTAL)" to Kconfig as the commit mentions.

  - Added `depends on ARM64 || X86_64` and `!UML` for now, since this is
    experimental, other architectures may require other changes (e.g.
    the issues I mentioned in the mailing list for ARM and UML) and they
    are not really tested so far. So let arch maintainers pick this up
    if they think it is worth it.

  - Gated the `cmd_ld_single` step also into the new mode, which also
    means that any possible future `objcopy` step is done after the
    translation, as expected.

  - Added `.gitignore` for `.bc` with exception for existing script.

  - Added `part-of-*` for helpers bitcode files as discussed, and
    dropped `$(if $(filter %_module.bc,$@),-DMODULE)` since `-DMODULE`
    is already there (would be duplicated otherwise).

  - Moved `LLVM_LINK` to keep binutils list alphabetized.

  - Fixed typo in title.

  - Dropped second `cmd_ld_single` commit message paragraph.

      - Miguel ]
Signed-off-by: Miguel Ojeda &lt;ojeda@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib: Move crypto library tests to Runtime Testing menu</title>
<updated>2026-03-24T00:50:59+00:00</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@kernel.org</email>
</author>
<published>2026-03-22T03:24:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7ac21b4032e5b9b8a6a312b6f1d54f4ba24d1c16'/>
<id>7ac21b4032e5b9b8a6a312b6f1d54f4ba24d1c16</id>
<content type='text'>
Currently the kconfig options for the crypto library KUnit tests appear
in the menu:

    -&gt; Library routines
      -&gt; Crypto library routines

However, this is the only content of "Crypto library routines".  I.e.,
it is empty when CONFIG_KUNIT=n.  This is because the crypto library
routines themselves don't have (or need to have) prompts.

Since this usually ends up as an unnecessary empty menu, let's remove
this menu and instead source the lib/crypto/tests/Kconfig file from
lib/Kconfig.debug inside the "Runtime Testing" menu:

    -&gt; Kernel hacking
      -&gt; Kernel Testing and Coverage
        -&gt; Runtime Testing

This puts the prompts alongside the ones for most of the other lib/
KUnit tests.  This seems to be a much better match to how the kconfig
menus are organized.

Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Tested-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Link: https://lore.kernel.org/r/20260322032438.286296-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently the kconfig options for the crypto library KUnit tests appear
in the menu:

    -&gt; Library routines
      -&gt; Crypto library routines

However, this is the only content of "Crypto library routines".  I.e.,
it is empty when CONFIG_KUNIT=n.  This is because the crypto library
routines themselves don't have (or need to have) prompts.

Since this usually ends up as an unnecessary empty menu, let's remove
this menu and instead source the lib/crypto/tests/Kconfig file from
lib/Kconfig.debug inside the "Runtime Testing" menu:

    -&gt; Kernel hacking
      -&gt; Kernel Testing and Coverage
        -&gt; Runtime Testing

This puts the prompts alongside the ones for most of the other lib/
KUnit tests.  This seems to be a much better match to how the kconfig
menus are organized.

Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Tested-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Link: https://lore.kernel.org/r/20260322032438.286296-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers &lt;ebiggers@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lockdep: Raise default stack trace limits when KASAN is enabled</title>
<updated>2026-03-16T12:16:49+00:00</updated>
<author>
<name>Mikhail Gavrilov</name>
<email>mikhail.v.gavrilov@gmail.com</email>
</author>
<published>2026-03-13T17:10:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=891626973b2faf468565a253ca55373e0b9675de'/>
<id>891626973b2faf468565a253ca55373e0b9675de</id>
<content type='text'>
KASAN-enabled kernels with LOCKDEP and PREEMPT_FULL hit
"BUG: MAX_STACK_TRACE_ENTRIES too low!" within 9-23 hours of normal
desktop use.

The root cause is a feedback loop between KASAN slab tracking and
lockdep: every KASAN-tracked slab allocation saves a stack trace via
stack_trace_save() -&gt; arch_stack_walk().  The unwinder calls
is_bpf_text_address(), which under PREEMPT_FULL can trigger RCU
deferred quiescent-state processing -&gt; swake_up_one() -&gt; lock_acquire()
-&gt; lockdep validate_chain() -&gt; save_trace().  This means KASAN's own
stack captures indirectly generate new lockdep dependency chains,
consuming the buffer from both directions.

/proc/lockdep_stats at the moment of overflow confirms that
stack-trace entries is the sole exhausted resource:

  stack-trace entries:  524288 [max: 524288]  &lt;- 100% full
  number of stack traces:            22080    &lt;- unique after dedup
  dependency chains:    164665 [max: 524288]  &lt;- only 31% used
  direct dependencies:   45270 [max:  65536]  &lt;- 69%
  lock-classes:           2811 [max:   8192]  &lt;- 34%

22080 genuinely unique traces averaging ~24 frames each fill the
buffer in under a day.  The hash-based deduplication (12593b7467f9) is
working correctly -- the traces are simply all different due to the
deep and varied call stacks from GPU + filesystem + Wine/Proton + KASAN
instrumentation.

Raise the LOCKDEP_STACK_TRACE_BITS default from 19 to 21 when KASAN is
enabled (2M entries, +12MB).  This is negligible compared to KASAN's
own shadow memory overhead (~12.5% of total RAM).  Scale
LOCKDEP_STACK_TRACE_HASH_BITS accordingly to maintain dedup efficiency.

Signed-off-by: Mikhail Gavrilov &lt;mikhail.v.gavrilov@gmail.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://patch.msgid.link/20260313171118.1702954-2-mikhail.v.gavrilov@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
KASAN-enabled kernels with LOCKDEP and PREEMPT_FULL hit
"BUG: MAX_STACK_TRACE_ENTRIES too low!" within 9-23 hours of normal
desktop use.

The root cause is a feedback loop between KASAN slab tracking and
lockdep: every KASAN-tracked slab allocation saves a stack trace via
stack_trace_save() -&gt; arch_stack_walk().  The unwinder calls
is_bpf_text_address(), which under PREEMPT_FULL can trigger RCU
deferred quiescent-state processing -&gt; swake_up_one() -&gt; lock_acquire()
-&gt; lockdep validate_chain() -&gt; save_trace().  This means KASAN's own
stack captures indirectly generate new lockdep dependency chains,
consuming the buffer from both directions.

/proc/lockdep_stats at the moment of overflow confirms that
stack-trace entries is the sole exhausted resource:

  stack-trace entries:  524288 [max: 524288]  &lt;- 100% full
  number of stack traces:            22080    &lt;- unique after dedup
  dependency chains:    164665 [max: 524288]  &lt;- only 31% used
  direct dependencies:   45270 [max:  65536]  &lt;- 69%
  lock-classes:           2811 [max:   8192]  &lt;- 34%

22080 genuinely unique traces averaging ~24 frames each fill the
buffer in under a day.  The hash-based deduplication (12593b7467f9) is
working correctly -- the traces are simply all different due to the
deep and varied call stacks from GPU + filesystem + Wine/Proton + KASAN
instrumentation.

Raise the LOCKDEP_STACK_TRACE_BITS default from 19 to 21 when KASAN is
enabled (2M entries, +12MB).  This is negligible compared to KASAN's
own shadow memory overhead (~12.5% of total RAM).  Scale
LOCKDEP_STACK_TRACE_HASH_BITS accordingly to maintain dedup efficiency.

Signed-off-by: Mikhail Gavrilov &lt;mikhail.v.gavrilov@gmail.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://patch.msgid.link/20260313171118.1702954-2-mikhail.v.gavrilov@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'core-debugobjects-2026-03-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2026-03-01T21:32:32+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-03-01T21:32:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e2bd1b136926f1ff65d4e0f87ac49b9a4621238c'/>
<id>e2bd1b136926f1ff65d4e0f87ac49b9a4621238c</id>
<content type='text'>
Pull debugobjects fix from Thomas Gleixner:
 "A single fix for debugobjects.

  The deferred page initialization prevents debug objects from
  allocating slab pages until the initialization is complete. That
  causes depletion of the pool and disabling of debugobjects.

  The reason is that debugobjects uses __GFP_HIGH for allocations as it
  might be invoked from arbitrary contexts. When PREEMPT_COUNT is
  disabled there is no way to know whether the context is safe to set
  __GFP_KSWAPD_RECLAIM.

  This worked until v6.18. Since then allocations w/o a reclaim flag
  cause new_slab() to end up in alloc_frozen_pages_nolock_noprof(),
  which returns early when deferred page initialization has not yet
  completed.

  Work around that when PREEMPT_COUNT is enabled as the preempt counter
  allows debugobjects to add __GFP_KSWAPD_RECLAIM to the GFP flags when
  the context is preemtible. When PREEMPT_COUNT is disabled the context
  is unknown and the reclaim bit can't be set because the caller might
  hold locks which might deadlock in the allocator.

  That makes debugobjects depend on PREEMPT_COUNT ||
  !DEFERRED_STRUCT_PAGE_INIT, which limits the coverage slightly, but
  keeps it functional for most cases"

* tag 'core-debugobjects-2026-03-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  debugobject: Make it work with deferred page initialization - again
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull debugobjects fix from Thomas Gleixner:
 "A single fix for debugobjects.

  The deferred page initialization prevents debug objects from
  allocating slab pages until the initialization is complete. That
  causes depletion of the pool and disabling of debugobjects.

  The reason is that debugobjects uses __GFP_HIGH for allocations as it
  might be invoked from arbitrary contexts. When PREEMPT_COUNT is
  disabled there is no way to know whether the context is safe to set
  __GFP_KSWAPD_RECLAIM.

  This worked until v6.18. Since then allocations w/o a reclaim flag
  cause new_slab() to end up in alloc_frozen_pages_nolock_noprof(),
  which returns early when deferred page initialization has not yet
  completed.

  Work around that when PREEMPT_COUNT is enabled as the preempt counter
  allows debugobjects to add __GFP_KSWAPD_RECLAIM to the GFP flags when
  the context is preemtible. When PREEMPT_COUNT is disabled the context
  is unknown and the reclaim bit can't be set because the caller might
  hold locks which might deadlock in the allocator.

  That makes debugobjects depend on PREEMPT_COUNT ||
  !DEFERRED_STRUCT_PAGE_INIT, which limits the coverage slightly, but
  keeps it functional for most cases"

* tag 'core-debugobjects-2026-03-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  debugobject: Make it work with deferred page initialization - again
</pre>
</div>
</content>
</entry>
</feed>
