From: Daniel Borkmann <dan...@iogearbox.net>
Date: Thu, 15 Dec 2016 01:30:06 +0100
> Commit 57a09bf0a416 ("bpf: Detect identical PTR_TO_MAP_VALUE_OR_NULL
> registers") introduced a regression where existing programs stopped
> loading due to reaching the verifier's maximum complexity limit,
> whereas prior to this commit they were loading just fine; the affected
> program has roughly 2k instructions.
>
> What was found is that state pruning couldn't be performed effectively
> anymore due to mismatches of the verifier's register state, in particular
> in the id tracking. It doesn't mean that 57a09bf0a416 is incorrect per
> se, but rather that verifier needs to perform a lot more work for the
> same program with regards to involved map lookups.
...
> Fixes: 57a09bf0a416 ("bpf: Detect identical PTR_TO_MAP_VALUE_OR_NULL
> registers")
> Signed-off-by: Daniel Borkmann <dan...@iogearbox.net>
> Acked-by: Thomas Graf <tg...@suug.ch>
> Acked-by: Alexei Starovoitov <a...@kernel.org>
Applied.
