Re: [PATCH] perf: fix segfault in `lock contention -b`

[Tycho Andersen]

On Tue, Jan 13, 2026 at 01:18:52PM -0800, Namhyung Kim wrote:
> On Mon, Jan 12, 2026 at 09:15:53AM -0700, Tycho Andersen wrote:
> > On Fri, Jan 09, 2026 at 04:49:01PM -0800, Namhyung Kim wrote:
> > > That said, can you add a NULL check in the init_numa_data() instead
> > > and see how far it can go?
> > 
> > Looks like not much further, it fails in lock_contention_bpf__load():
> > 
> > ./perf lock contention -b
> > libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled?
> > libbpf: failed to find valid kernel BTF
> > libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled?
> > libbpf: failed to find valid kernel BTF
> > libbpf: Error loading vmlinux BTF: -ESRCH
> > libbpf: failed to load BPF skeleton 'lock_contention_bpf': -ESRCH
> > Failed to load lock-contention BPF skeleton
> > lock contention BPF setup failed
> 
> Thanks for checking this.  I think it's ok to fail like this when BTF is
> not enabled.  Let me see if I can make some changes to run without it
> later.

Gentle ping, I was just reminded of this crash again this morning.

Tycho