Merge tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

- Support pulling non-linear xdp data with bpf_xdp_pull_data() kfu

Merge tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

- Support pulling non-linear xdp data with bpf_xdp_pull_data() kfunc
(Amery Hung)

Applied as a stable branch in bpf-next and net-next trees.

- Support reading skb metadata via bpf_dynptr (Jakub Sitnicki)

Also a stable branch in bpf-next and net-next trees.

- Enforce expected_attach_type for tailcall compatibility (Daniel
Borkmann)

- Replace path-sensitive with path-insensitive live stack analysis in
the verifier (Eduard Zingerman)

This is a significant change in the verification logic. More details,
motivation, long term plans are in the cover letter/merge commit.

- Support signed BPF programs (KP Singh)

This is another major feature that took years to materialize.

Algorithm details are in the cover letter/marge commit

- Add support for may_goto instruction to s390 JIT (Ilya Leoshkevich)

- Add support for may_goto instruction to arm64 JIT (Puranjay Mohan)

- Fix USDT SIB argument handling in libbpf (Jiawei Zhao)

- Allow uprobe-bpf program to change context registers (Jiri Olsa)

- Support signed loads from BPF arena (Kumar Kartikeya Dwivedi and
Puranjay Mohan)

- Allow access to union arguments in tracing programs (Leon Hwang)

- Optimize rcu_read_lock() + migrate_disable() combination where it's
used in BPF subsystem (Menglong Dong)

- Introduce bpf_task_work_schedule*() kfuncs to schedule deferred
execution of BPF callback in the context of a specific task using the
kernel’s task_work infrastructure (Mykyta Yatsenko)

- Enforce RCU protection for KF_RCU_PROTECTED kfuncs (Kumar Kartikeya
Dwivedi)

- Add stress test for rqspinlock in NMI (Kumar Kartikeya Dwivedi)

- Improve the precision of tnum multiplier verifier operation
(Nandakumar Edamana)

- Use tnums to improve is_branch_taken() logic (Paul Chaignon)

- Add support for atomic operations in arena in riscv JIT (Pu Lehui)

- Report arena faults to BPF error stream (Puranjay Mohan)

- Search for tracefs at /sys/kernel/tracing first in bpftool (Quentin
Monnet)

- Add bpf_strcasecmp() kfunc (Rong Tao)

- Support lookup_and_delete_elem command in BPF_MAP_STACK_TRACE (Tao
Chen)

* tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (197 commits)
libbpf: Replace AF_ALG with open coded SHA-256
selftests/bpf: Add stress test for rqspinlock in NMI
selftests/bpf: Add test case for different expected_attach_type
bpf: Enforce expected_attach_type for tailcall compatibility
bpftool: Remove duplicate string.h header
bpf: Remove duplicate crypto/sha2.h header
libbpf: Fix error when st-prefix_ops and ops from differ btf
selftests/bpf: Test changing packet data from kfunc
selftests/bpf: Add stacktrace map lookup_and_delete_elem test case
selftests/bpf: Refactor stacktrace_map case with skeleton
bpf: Add lookup_and_delete_elem for BPF_MAP_STACK_TRACE
selftests/bpf: Fix flaky bpf_cookie selftest
selftests/bpf: Test changing packet data from global functions with a kfunc
bpf: Emit struct bpf_xdp_sock type in vmlinux BTF
selftests/bpf: Task_work selftest cleanup fixes
MAINTAINERS: Delete inactive maintainers from AF_XDP
bpf: Mark kfuncs as __noclone
selftests/bpf: Add kprobe multi write ctx attach test
selftests/bpf: Add kprobe write ctx attach test
selftests/bpf: Add uprobe context ip register change test
...

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selftests/bpf: Add stress test for rqspinlock in NMI

Introduce a kernel module that will exercise lock acquisition in the NMI
path, and bias toward creating contention such that NMI waiters end up
b

selftests/bpf: Add stress test for rqspinlock in NMI

Introduce a kernel module that will exercise lock acquisition in the NMI
path, and bias toward creating contention such that NMI waiters end up
being non-head waiters. Prior to the rqspinlock fix made in the commit
0d80e7f951be ("rqspinlock: Choose trylock fallback for NMI waiters"), it
was possible for the queueing path of non-head waiters to get stuck in
NMI, which this stress test reproduces fairly easily with just 3 CPUs.

Both AA and ABBA flavors are supported, and it will serve as a test case
for future fixes that address this corner case. More information about
the problem in question is available in the commit cited above. When the
fix is reverted, this stress test will lock up the system.

To enable this test automatically through the test_progs infrastructure,
add a load_module_params API to exercise both AA and ABBA cases when
running the test.

Note that the test runs for at most 5 seconds, and becomes a noop after
that, in order to allow the system to make forward progress. In
addition, CPU 0 is always kept untouched by the created threads and
NMIs. The test will automatically scale to the number of available
online CPUs.

Note that at least 3 CPUs are necessary to run this test, hence skip the
selftest in case the environment has less than 3 CPUs available.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250927205304.199760-1-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

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