From: Tycho Andersen <tycho@kernel.org>
To: Namhyung Kim <namhyung@kernel.org>,
Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@kernel.org>, Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
James Clark <james.clark@linaro.org>,
Chun-Tse Shao <ctshao@google.com>,
linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
Ravi Bangoria <ravi.bangoria@amd.com>,
K Prateek Nayak <kprateek.nayak@amd.com>
Subject: Re: [PATCH] perf: fix segfault in `lock contention -b`
Date: Wed, 4 Feb 2026 08:20:34 -0700 [thread overview]
Message-ID: <aYNjwvYkvk0Ul2Jl@tycho.pizza> (raw)
In-Reply-To: <aWa2vDy_0QGh_a20@google.com>
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
next prev parent reply other threads:[~2026-02-04 15:20 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-09 16:44 [PATCH] perf: fix segfault in `lock contention -b` Tycho Andersen
2026-01-10 0:49 ` Namhyung Kim
2026-01-12 16:15 ` Tycho Andersen
2026-01-13 21:18 ` Namhyung Kim
2026-02-04 15:20 ` Tycho Andersen [this message]
2026-02-04 21:26 ` Namhyung Kim
2026-01-13 3:11 ` K Prateek Nayak
2026-01-13 15:48 ` Tycho Andersen
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