[bpf-next,v4,0/2] bpf,arm64: Add support for BPF Arena

Message

Puranjay Mohan March 25, 2024, 3:07 p.m. UTC

Changes in V4
V3: https://lore.kernel.org/bpf/[e-mail]/
- Use more descriptive variable names.
- Use insn_is_cast_user() helper.

Changes in V3
V2: https://lore.kernel.org/bpf/[e-mail]/
- Optimize bpf_addr_space_cast as suggested by Xu Kuohai

Changes in V2
V1: https://lore.kernel.org/bpf/[e-mail]/
- 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

This will need the patch [1] that introduced insn_is_cast_user() helper to
build.

The verifier_arena selftest could fail in the CI because the following
commit[2] is missing from bpf-next:


[1] https://lore.kernel.org/bpf/[e-mail]/
[2] https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=fa3550dca8f02ec312727653a94115ef3ab68445

Here is a CI run with all dependencies added: https://github.com/kernel-patches/bpf/pull/6641

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                | 86 +++++++++++++++++---
 tools/testing/selftests/bpf/DENYLIST.aarch64 |  2 -
 2 files changed, 76 insertions(+), 12 deletions(-)

Comments

[e-mail] April 3, 2024, 2:50 a.m. UTC | #1

Hello:

This series was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <[e-mail]>:

On Mon, 25 Mar 2024 15:07:14 +0000 you wrote:
> Changes in V4
> V3: https://lore.kernel.org/bpf/[e-mail]/
> - Use more descriptive variable names.
> - Use insn_is_cast_user() helper.
> 
> Changes in V3
> V2: https://lore.kernel.org/bpf/[e-mail]/
> - Optimize bpf_addr_space_cast as suggested by Xu Kuohai
> 
> [...]

Here is the summary with links:
  - [bpf-next,v4,1/2] bpf: Add arm64 JIT support for PROBE_MEM32 pseudo instructions.
    https://git.kernel.org/bpf/bpf-next/c/339af577ec05
  - [bpf-next,v4,2/2] bpf: Add arm64 JIT support for bpf_addr_space_cast instruction.
    https://git.kernel.org/bpf/bpf-next/c/4dd31243e308

You are awesome, thank you!