[PATCH bpf-next v3 0/2] bpf,arm64: Add support for BPF Arena

From: Puranjay Mohan
Date: Sat Mar 23 2024 - 06:31:17 EST


Changes in V3
V2: https://lore.kernel.org/bpf/20240321153102.103832-1-puranjay12@xxxxxxxxx/
- Optimize bpf_addr_space_cast as suggested by Xu Kuohai

Changes in V2
V1: https://lore.kernel.org/bpf/20240314150003.123020-1-puranjay12@xxxxxxxxx/
- Fix build warnings by using 5 in place of 32 as DONT_CLEAR marker.
R5 is not mapped to any BPF register so it can safely be used here.

This series adds the support for PROBE_MEM32 and bpf_addr_space_cast
instructions to the ARM64 BPF JIT. These two instructions allow the
enablement of BPF Arena.

All arena related selftests are passing.

[root@ip-172-31-6-62 bpf]# ./test_progs -a "*arena*"
#3/1 arena_htab/arena_htab_llvm:OK
#3/2 arena_htab/arena_htab_asm:OK
#3 arena_htab:OK
#4/1 arena_list/arena_list_1:OK
#4/2 arena_list/arena_list_1000:OK
#4 arena_list:OK
#434/1 verifier_arena/basic_alloc1:OK
#434/2 verifier_arena/basic_alloc2:OK
#434/3 verifier_arena/basic_alloc3:OK
#434/4 verifier_arena/iter_maps1:OK
#434/5 verifier_arena/iter_maps2:OK
#434/6 verifier_arena/iter_maps3:OK
#434 verifier_arena:OK
Summary: 3/10 PASSED, 0 SKIPPED, 0 FAILED

The verifier_arena selftest could fail in the CI because the following
commit is missing from bpf-next:
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=fa3550dca8f02ec312727653a94115ef3ab68445

Puranjay Mohan (2):
bpf: Add arm64 JIT support for PROBE_MEM32 pseudo instructions.
bpf: Add arm64 JIT support for bpf_addr_space_cast instruction.

arch/arm64/net/bpf_jit_comp.c | 87 +++++++++++++++++---
tools/testing/selftests/bpf/DENYLIST.aarch64 | 2 -
2 files changed, 77 insertions(+), 12 deletions(-)

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2.40.1