Re: [PATCH 5.15 0/6] Backporting for 5.15 test_verifier failed

[Pu Lehui <pulehui@huawei.com>]

Hi Luiz,

My local 5.15 environment is a little bit weird, could you help me to 
test it?

On 2023/8/4 23:24, Pu Lehui wrote:
> Luiz Capitulino reported the test_verifier test failed:
> "precise: ST insn causing spi > allocated_stack".
> And it was introduced by the following upstream commit:
> ecdf985d7615 ("bpf: track immediate values written to stack by BPF_ST instruction")
> 
> Eduard's investigation [4] shows that test failure is not a bug, but a
> difference in BPF verifier behavior between upstream, where commits
> [1,2,3] by Andrii are present, and 5.15, where these commits are absent.
> 
> Backporting strategy is consistent with Eduard in kernel version 6.1 [5],
> but with some conflicts in patch #1, #4 and #6 due to the bpf of 5.15
> doesn't support more features.
> 
> Commits of Andrii:
> [1] be2ef8161572 ("bpf: allow precision tracking for programs with subprogs")
> [2] f63181b6ae79 ("bpf: stop setting precise in current state")
> [3] 7a830b53c17b ("bpf: aggressively forget precise markings during state checkpointing")
> 
> Links:
> [4] https://lore.kernel.org/stable/c9b10a8a551edafdfec855fbd35757c6238ad258.camel@gmail.com/
> [5] https://lore.kernel.org/all/20230724124223.1176479-2-eddyz87@gmail.com/
> 
> Andrii Nakryiko (4):
>    bpf: allow precision tracking for programs with subprogs
>    bpf: stop setting precise in current state
>    bpf: aggressively forget precise markings during state checkpointing
>    selftests/bpf: make test_align selftest more robust
> 
> Ilya Leoshkevich (1):
>    selftests/bpf: Fix sk_assign on s390x
> 
> Yonghong Song (1):
>    selftests/bpf: Workaround verification failure for
>      fexit_bpf2bpf/func_replace_return_code
> 
>   kernel/bpf/verifier.c                         | 199 ++++++++++++++++--
>   .../testing/selftests/bpf/prog_tests/align.c  |  36 ++--
>   .../selftests/bpf/prog_tests/sk_assign.c      |  25 ++-
>   .../selftests/bpf/progs/connect4_prog.c       |   2 +-
>   .../selftests/bpf/progs/test_sk_assign.c      |  11 +
>   .../bpf/progs/test_sk_assign_libbpf.c         |   3 +
>   6 files changed, 243 insertions(+), 33 deletions(-)
>   create mode 100644 tools/testing/selftests/bpf/progs/test_sk_assign_libbpf.c
>