On Thu, 3 Oct 2024 11:16:38 -0400 Mathieu Desnoyers <[email protected]> wrote:
> Add a might_fault() check to validate that the bpf sys_enter/sys_exit > probe callbacks are indeed called from a context where page faults can > be handled. > > Signed-off-by: Mathieu Desnoyers <[email protected]> > Acked-by: Andrii Nakryiko <[email protected]> > Tested-by: Andrii Nakryiko <[email protected]> # BPF parts > Cc: Michael Jeanson <[email protected]> > Cc: Steven Rostedt <[email protected]> > Cc: Masami Hiramatsu <[email protected]> > Cc: Peter Zijlstra <[email protected]> > Cc: Alexei Starovoitov <[email protected]> > Cc: Yonghong Song <[email protected]> > Cc: Paul E. McKenney <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Arnaldo Carvalho de Melo <[email protected]> > Cc: Mark Rutland <[email protected]> > Cc: Alexander Shishkin <[email protected]> > Cc: Namhyung Kim <[email protected]> > Cc: Andrii Nakryiko <[email protected]> > Cc: [email protected] > Cc: Joel Fernandes <[email protected]> > --- > include/trace/bpf_probe.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/include/trace/bpf_probe.h b/include/trace/bpf_probe.h > index 211b98d45fc6..099df5c3e38a 100644 > --- a/include/trace/bpf_probe.h > +++ b/include/trace/bpf_probe.h > @@ -57,6 +57,7 @@ __bpf_trace_##call(void *__data, proto) > \ > static notrace void \ > __bpf_trace_##call(void *__data, proto) > \ > { \ > + might_fault(); \ And I think this gets called at places that do not allow faults. -- Steve > guard(preempt_notrace)(); \ > CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(__data, > CAST_TO_U64(args)); \ > }
