Re: [bpf-next PATCH 0/4] verifier, improve ptr is_branch_taken logic

2020-05-18 Thread Andrii Nakryiko
On Mon, May 18, 2020 at 1:05 PM John Fastabend wrote: > > Verifier logic to track pointer is_branch_taken logic to prune paths > that can not be taken. For many types we track if the pointer is null I re-read first sentence many times, still not sure what it is saying. Do you mind rephrasing it a

[bpf-next PATCH 0/4] verifier, improve ptr is_branch_taken logic

2020-05-18 Thread John Fastabend
Verifier logic to track pointer is_branch_taken logic to prune paths that can not be taken. For many types we track if the pointer is null or not. We can then use this information when calculating if branches are taken when jump is comparing if pointer is null or not. First patch is the verifier l