This patch series introduces support for the PROBE_MEM32, bpf_addr_space_cast and PROBE_ATOMIC instructions in the powerpc BPF JIT, facilitating the implementation of BPF arena and arena atomics.
All selftests related to bpf_arena, bpf_arena_atomic(except load_acquire/store_release) enablement are passing:
# ./test_progs -t arena_list #5/1 arena_list/arena_list_1:OK #5/2 arena_list/arena_list_1000:OK #5 arena_list:OK Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED
# ./test_progs -t arena_htab #4/1 arena_htab/arena_htab_llvm:OK #4/2 arena_htab/arena_htab_asm:OK #4 arena_htab:OK Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED
# ./test_progs -t verifier_arena #464/1 verifier_arena/basic_alloc1:OK #464/2 verifier_arena/basic_alloc2:OK #464/3 verifier_arena/basic_alloc3:OK #464/4 verifier_arena/iter_maps1:OK #464/5 verifier_arena/iter_maps2:OK #464/6 verifier_arena/iter_maps3:OK #464 verifier_arena:OK #465/1 verifier_arena_large/big_alloc1:OK #465/2 verifier_arena_large/big_alloc2:OK #465 verifier_arena_large:OK Summary: 2/8 PASSED, 0 SKIPPED, 0 FAILED
# ./test_progs -t arena_atomics #3/1 arena_atomics/add:OK #3/2 arena_atomics/sub:OK #3/3 arena_atomics/and:OK #3/4 arena_atomics/or:OK #3/5 arena_atomics/xor:OK #3/6 arena_atomics/cmpxchg:OK #3/7 arena_atomics/xchg:OK #3/8 arena_atomics/uaf:OK #3/9 arena_atomics/load_acquire:SKIP #3/10 arena_atomics/store_release:SKIP #3 arena_atomics:OK (SKIP: 2/10) Summary: 1/8 PASSED, 2 SKIPPED, 0 FAILED
Changes since v2: * Dropped arena_spin_lock selftest fix patch from the patchset as it has to go via bpf-next while these changes will go via powerpc tree.
v2:https://lore.kernel.org/all/20250829165135.1273071-1-skb99@linux.ibm.com/
Changes since v1:
Addressed comments from Chris: * Squashed introduction of bpf_jit_emit_probe_mem_store() and its usage in one patch. * Defined and used PPC_RAW_RLDICL_DOT to avoid the CMPDI. * Removed conditional statement for fixup[0] = PPC_RAW_LI(dst_reg, 0); * Indicated this change is limited to powerpc64 in subject.
Addressed comments from Alexei: * Removed skel->rodata->nr_cpus = get_nprocs() and its usage to get currently online cpus(as it needs to be updated from userspace).
Addressed comments from Hari: * Updated the bpf jit stack layout and associated macros to accommodate new NVR.
v1:https://lore.kernel.org/all/20250805062747.3479221-1-skb99@linux.ibm.com/
Saket Kumar Bhaskar (4): powerpc64/bpf: Implement PROBE_MEM32 pseudo instructions powerpc64/bpf: Implement bpf_addr_space_cast instruction powerpc64/bpf: Introduce bpf_jit_emit_atomic_ops() to emit atomic instructions powerpc64/bpf: Implement PROBE_ATOMIC instructions
arch/powerpc/include/asm/ppc-opcode.h | 1 + arch/powerpc/net/bpf_jit.h | 6 +- arch/powerpc/net/bpf_jit_comp.c | 32 +- arch/powerpc/net/bpf_jit_comp32.c | 2 +- arch/powerpc/net/bpf_jit_comp64.c | 401 +++++++++++++++++++------- 5 files changed, 330 insertions(+), 112 deletions(-)