LoongArch: BPF: arena features, exceptions, private stack and may

From:		George Guo <dongtai.guo-AT-linux.dev>
To:		Huacai Chen <chenhuacai-AT-kernel.org>, Tiezhu Yang <yangtiezhu-AT-loongson.cn>, Hengqi Chen <hengqi.chen-AT-gmail.com>, Alexei Starovoitov <ast-AT-kernel.org>, Daniel Borkmann <daniel-AT-iogearbox.net>, Andrii Nakryiko <andrii-AT-kernel.org>
Subject:		[PATCH bpf-next v2 00/11] LoongArch: BPF: arena features, exceptions, private stack and may_goto
Date:		Thu, 02 Jul 2026 10:23:11 +0800
Message-ID:		<20260702022322.51033-1-dongtai.guo@linux.dev>
Cc:		WANG Xuerui <kernel-AT-xen0n.name>, Martin KaFai Lau <martin.lau-AT-linux.dev>, Eduard Zingerman <eddyz87-AT-gmail.com>, Kumar Kartikeya Dwivedi <memxor-AT-gmail.com>, Song Liu <song-AT-kernel.org>, Yonghong Song <yonghong.song-AT-linux.dev>, Jiri Olsa <jolsa-AT-kernel.org>, George Guo <guodongtai-AT-kylinos.cn>, bpf-AT-vger.kernel.org, loongarch-AT-lists.linux.dev, linux-kernel-AT-vger.kernel.org
Archive-link:		Article

This series adds the remaining LoongArch BPF JIT features and enables the
matching selftests:

  - internal-only MOV for per-CPU address resolution
  - timed may_goto
  - per-program private stacks
  - exceptions (bpf_throw)
  - sign-extending loads from arena (PROBE_MEM32SX)
  - atomics on arena pointers (PROBE_ATOMIC)
  - selftests: struct_ops private stack, arena LDSX, arena atomics, and a
    LoongArch deny list

Patch 1 ("LoongArch: BPF: Fix tail call count pointer offset for arena
programs") is the same fix already posted separately for the bpf tree;
several patches in this series (notably exceptions, patch 5) build on
top of the helper it introduces, so it is included here, unchanged, to
keep the series self-contained and applicable on bpf-next. It can be
dropped once it lands via the bpf tree.

  LoongArch: BPF: Fix tail call count pointer offset for arena programs
  https://lore.kernel.org/all/20260629085511.359546-1-dongt...

Based on 7.2-rc1.

v2:
 - Included the tail call count pointer offset fix as patch 1/11 (see
   above) instead of only referencing it, so the series applies cleanly
   on bpf-next without waiting on the bpf tree; the empty prog_array
   off-by-one was fixed independently upstream by commit 0379d10f09bc
   ("LoongArch: BPF: Fix off-by-one error in tail call"), now in 7.2-rc1.
 - timed may_goto: store $ra at the ORC-mandated .ra_offset = -8 slot in
   the trampoline (it was stored at the wrong slot in v1), per Tiezhu
   Yang's review.
 - Consolidated the earlier per-CPU MOV / timed may_goto and arena gating
   postings into one series; rebased on 7.2-rc1.
 - selftests: use the upstream __arch_loongarch / "LOONGARCH" test_loader
   support now in 7.2-rc1 instead of introducing it.
 - Prior postings:
   https://lore.kernel.org/all/20260609041407.122384-1-dongt...
   https://lore.kernel.org/all/20260618033809.98253-1-dongta...

George Guo (11):
  LoongArch: BPF: Fix tail call count pointer offset for arena programs
  LoongArch: BPF: Support internal-only MOV to resolve per-CPU addrs
  LoongArch: BPF: Add timed may_goto support
  LoongArch: BPF: Add private stack support
  LoongArch: BPF: Add exceptions (bpf_throw) support
  LoongArch: BPF: Support sign-extending loads from arena
  LoongArch: BPF: Support atomics on arena pointers
  selftests/bpf: Enable struct_ops private stack test for LoongArch
  selftests/bpf: Enable arena LDSX tests on LoongArch
  selftests/bpf: Enable arena atomics tests on LoongArch
  selftests/bpf: Add LoongArch deny list

 arch/loongarch/include/asm/inst.h             |   1 +
 arch/loongarch/kernel/stacktrace.c            |  52 +++
 arch/loongarch/net/Makefile                   |   2 +-
 arch/loongarch/net/bpf_jit.c                  | 397 ++++++++++++++++--
 arch/loongarch/net/bpf_jit.h                  |   1 +
 arch/loongarch/net/bpf_timed_may_goto.S       |  47 +++
 .../testing/selftests/bpf/DENYLIST.loongarch  |   1 +
 .../bpf/prog_tests/struct_ops_private_stack.c |   2 +-
 .../selftests/bpf/progs/arena_atomics.c       |   3 +
 .../selftests/bpf/progs/verifier_ldsx.c       |  17 +
 10 files changed, 485 insertions(+), 38 deletions(-)
 create mode 100644 arch/loongarch/net/bpf_timed_may_goto.S
 create mode 100644 tools/testing/selftests/bpf/DENYLIST.loongarch

-- 
2.25.1

LoongArch: BPF: arena features, exceptions, private stack and may_goto