On Fri, Aug 04, 2023 at 11:24:53PM +0800, 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@xxxxxxxxx/
> [5] https://lore.kernel.org/all/20230724124223.1176479-2-eddyz87@xxxxxxxxx/
>
This, and the 5.10.y series, now queued up, thanks.
greg k-h
