Dear BPF experts, I'm working on collecting some kernel performance data using BPF tracing prog. Our performance profiling team wants to associate the data with user stack information. One of the requirements is to reliably get BuildIDs from bpf_get_stackid() and other similar helpers [1]. As part of an early investigation, we found that there are a couple issues that make bpf_get_stackid() much less reliable than we'd like for our use: 1. The first page of many binaries (which contains the ELF headers and thus the BuildID that we need) is often not in memory. The failure of find_get_page() (called from build_id_parse()) is higher than we would want. 2. When anonymous huge pages are used to hold some regions of process text, build_id_parse() also fails to get a BuildID because vma->vm_file is NULL. These two issues are critical blockers for us to use BPF in production. Can we do better? What do other users do to reliably get build ids? Thanks very much, Hao [1] https://man7.org/linux/man-pages/man7/bpf-helpers.7.html
