| #
f17b474e |
| 10-Feb-2026 |
Linus Torvalds <torvalds@linux-foundation.org> |
Merge tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Support associating BPF program with struct_ops (Amery Hung)
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Merge tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Support associating BPF program with struct_ops (Amery Hung)
- Switch BPF local storage to rqspinlock and remove recursion detection counters which were causing false positives (Amery Hung)
- Fix live registers marking for indirect jumps (Anton Protopopov)
- Introduce execution context detection BPF helpers (Changwoo Min)
- Improve verifier precision for 32bit sign extension pattern (Cupertino Miranda)
- Optimize BTF type lookup by sorting vmlinux BTF and doing binary search (Donglin Peng)
- Allow states pruning for misc/invalid slots in iterator loops (Eduard Zingerman)
- In preparation for ASAN support in BPF arenas teach libbpf to move global BPF variables to the end of the region and enable arena kfuncs while holding locks (Emil Tsalapatis)
- Introduce support for implicit arguments in kfuncs and migrate a number of them to new API. This is a prerequisite for cgroup sub-schedulers in sched-ext (Ihor Solodrai)
- Fix incorrect copied_seq calculation in sockmap (Jiayuan Chen)
- Fix ORC stack unwind from kprobe_multi (Jiri Olsa)
- Speed up fentry attach by using single ftrace direct ops in BPF trampolines (Jiri Olsa)
- Require frozen map for calculating map hash (KP Singh)
- Fix lock entry creation in TAS fallback in rqspinlock (Kumar Kartikeya Dwivedi)
- Allow user space to select cpu in lookup/update operations on per-cpu array and hash maps (Leon Hwang)
- Make kfuncs return trusted pointers by default (Matt Bobrowski)
- Introduce "fsession" support where single BPF program is executed upon entry and exit from traced kernel function (Menglong Dong)
- Allow bpf_timer and bpf_wq use in all programs types (Mykyta Yatsenko, Andrii Nakryiko, Kumar Kartikeya Dwivedi, Alexei Starovoitov)
- Make KF_TRUSTED_ARGS the default for all kfuncs and clean up their definition across the tree (Puranjay Mohan)
- Allow BPF arena calls from non-sleepable context (Puranjay Mohan)
- Improve register id comparison logic in the verifier and extend linked registers with negative offsets (Puranjay Mohan)
- In preparation for BPF-OOM introduce kfuncs to access memcg events (Roman Gushchin)
- Use CFI compatible destructor kfunc type (Sami Tolvanen)
- Add bitwise tracking for BPF_END in the verifier (Tianci Cao)
- Add range tracking for BPF_DIV and BPF_MOD in the verifier (Yazhou Tang)
- Make BPF selftests work with 64k page size (Yonghong Song)
* tag 'bpf-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (268 commits) selftests/bpf: Fix outdated test on storage->smap selftests/bpf: Choose another percpu variable in bpf for btf_dump test selftests/bpf: Remove test_task_storage_map_stress_lookup selftests/bpf: Update task_local_storage/task_storage_nodeadlock test selftests/bpf: Update task_local_storage/recursion test selftests/bpf: Update sk_storage_omem_uncharge test bpf: Switch to bpf_selem_unlink_nofail in bpf_local_storage_{map_free, destroy} bpf: Support lockless unlink when freeing map or local storage bpf: Prepare for bpf_selem_unlink_nofail() bpf: Remove unused percpu counter from bpf_local_storage_map_free bpf: Remove cgroup local storage percpu counter bpf: Remove task local storage percpu counter bpf: Change local_storage->lock and b->lock to rqspinlock bpf: Convert bpf_selem_unlink to failable bpf: Convert bpf_selem_link_map to failable bpf: Convert bpf_selem_unlink_map to failable bpf: Select bpf_local_storage_map_bucket based on bpf_local_storage selftests/xsk: fix number of Tx frags in invalid packet selftests/xsk: properly handle batch ending in the middle of a packet bpf: Prevent reentrance into call_rcu_tasks_trace() ...
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| #
b236134f |
| 21-Jan-2026 |
Alexei Starovoitov <ast@kernel.org> |
Merge branch 'bpf-kernel-functions-with-kf_implicit_args'
Ihor Solodrai says:
==================== bpf: Kernel functions with KF_IMPLICIT_ARGS
This series implements a generic "implicit arguments"
Merge branch 'bpf-kernel-functions-with-kf_implicit_args'
Ihor Solodrai says:
==================== bpf: Kernel functions with KF_IMPLICIT_ARGS
This series implements a generic "implicit arguments" feature for BPF kernel functions. For context see prior work [1][2].
A mechanism is created for kfuncs to have arguments that are not visible to the BPF programs, and are provided to the kernel function implementation by the verifier.
This mechanism is then used in the kfuncs that have a parameter with __prog annotation [3], which is the current way of passing struct bpf_prog_aux pointer to kfuncs.
The function with implicit arguments is defined by KF_IMPLICIT_ARGS flag in BTF_IDS_FLAGS set. In this series, only a pointer to struct bpf_prog_aux can be implicit, although it is simple to extend this to more types.
The verifier handles a kfunc with KF_IMPLICIT_ARGS by resolving it to a different (actual) BTF prototype early in verification (patch #3).
A <kfunc>_impl function generated in BTF for a kfunc with implicit args does not have a "bpf_kfunc" decl tag, and a kernel address. The verifier will reject a program trying to call such an _impl kfunc.
The usage of <kfunc>_impl functions in BPF is only allowed for kfuncs with an explicit kernel (or kmodule) declaration, that is in "legacy" cases. As of this series, there are no legacy kernel functions, as all __prog users are migrated to KF_IMPLICIT_ARGS. However the implementation allows for legacy cases support in principle.
The series removes the following BPF kernel functions: - bpf_stream_vprintk_impl - bpf_task_work_schedule_resume_impl - bpf_task_work_schedule_signal_impl - bpf_wq_set_callback_impl
This will break existing BPF programs calling these functions (the verifier will not load them) on new kernels.
To mitigate, BPF users are advised to use the following pattern [4]:
if (xxx_impl) xxx_impl(..., NULL); else xxx(...);
Which can be wrapped in a macro.
The series consists of the following patches: - patches #1 and #2 are non-functional refactoring in kernel/bpf - patch #3 defines KF_IMPLICIT_ARGS flag and teaches the verifier about it - patches #4-#5 implement btf2btf transformation in resolve_btfids - patch #6 adds selftests specific to KF_IMPLICIT_ARGS feature - patches #7-#11 migrate the current users of __prog argument to KF_IMPLICIT_ARGS - patch #12 removes __prog arg suffix support from the kernel - patch #13 updates the docs
[1] https://lore.kernel.org/bpf/20251029190113.3323406-1-ihor.solodrai@linux.dev/ [2] https://lore.kernel.org/bpf/20250924211716.1287715-1-ihor.solodrai@linux.dev/ [3] https://docs.kernel.org/bpf/kfuncs.html#prog-annotation [4] https://lore.kernel.org/bpf/CAEf4BzbgPfRm9BX=TsZm-TsHFAHcwhPY4vTt=9OT-uhWqf8tqw@mail.gmail.com/ ---
v2->v3: - resolve_btfids: Use dynamic reallocation for btf2btf_context arrays (Andrii) - resolve_btfids: Add missing free() for btf2btf_context arrays (AI) - Other nits in resolve_btfids (Andrii, Eduard)
v2: https://lore.kernel.org/bpf/20260116201700.864797-1-ihor.solodrai@linux.dev/
v1->v2: - Replace the following kernel functions with KF_IMPLICIT_ARGS version: - bpf_stream_vprintk_impl -> bpf_stream_vprintk - bpf_task_work_schedule_resume_impl -> bpf_task_work_schedule_resume - bpf_task_work_schedule_signal_impl -> bpf_task_work_schedule_signal - bpf_wq_set_callback_impl -> bpf_wq_set_callback_impl - Remove __prog arg suffix support from the verifier - Rework btf2btf implementation in resolve_btfids - Do distill base and sort before BTF_ids patching - Collect kfuncs based on BTF decl tags, before BTF_ids are patched - resolve_btfids: use dynamic memory for intermediate data (Andrii) - verifier: reset .subreg_def for caller saved registers on kfunc call (Eduard) - selftests/hid: remove Makefile changes (Benjamin) - selftests/bpf: Add a patch (#11) migrating struct_ops_assoc test to KF_IMPLICIT_ARGS - Various nits across the series (Alexei, Andrii, Eduard)
v1: https://lore.kernel.org/bpf/20260109184852.1089786-1-ihor.solodrai@linux.dev/
--- ====================
Link: https://patch.msgid.link/20260120222638.3976562-1-ihor.solodrai@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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| #
e939f3d1 |
| 20-Jan-2026 |
Ihor Solodrai <ihor.solodrai@linux.dev> |
selftests/bpf: Add tests for KF_IMPLICIT_ARGS
Add trivial end-to-end tests to validate that KF_IMPLICIT_ARGS flag is properly handled by both resolve_btfids and the verifier.
Declare kfuncs in bpf_
selftests/bpf: Add tests for KF_IMPLICIT_ARGS
Add trivial end-to-end tests to validate that KF_IMPLICIT_ARGS flag is properly handled by both resolve_btfids and the verifier.
Declare kfuncs in bpf_testmod. Check that bpf_prog_aux pointer is set in the kfunc implementation. Verify that calls with implicit args and a legacy case all work.
Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Link: https://lore.kernel.org/r/20260120222638.3976562-7-ihor.solodrai@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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