On Mon, Jun 05, 2023 at 03:30:20PM +0800, sunliming wrote: > The user_events support events that has empty arguments. But the trace event > is discarded and not really committed when the arguments is empty. Fix this > by not attempting to copy in zero-length data. > > Signed-off-by: sunliming <sunliming@xxxxxxxxxx> > --- This series looks good to me, functionally. I applied it locally and ran this code with the new test additions. Everything works well. Thank you! The only thing I ask before an ACK is patch 2 and 4 in the series only use "user_events: " prefix. Can you change these to "selftests/user_events: "? You marked 3 this way, so I'd like to stick with a consistent form: I think it would be good going forward we use "tracing/user_events" for functional changes and "selftests/user_events" for self test changes. Thanks, -Beau > kernel/trace/trace_events_user.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c > index 0d91dac206ff..698703a3d234 100644 > --- a/kernel/trace/trace_events_user.c > +++ b/kernel/trace/trace_events_user.c > @@ -1399,7 +1399,7 @@ static void user_event_ftrace(struct user_event *user, struct iov_iter *i, > if (unlikely(!entry)) > return; > > - if (unlikely(!copy_nofault(entry + 1, i->count, i))) > + if (unlikely(i->count != 0 && !copy_nofault(entry + 1, i->count, i))) > goto discard; > > if (!list_empty(&user->validators) && > @@ -1440,7 +1440,7 @@ static void user_event_perf(struct user_event *user, struct iov_iter *i, > > perf_fetch_caller_regs(regs); > > - if (unlikely(!copy_nofault(perf_entry + 1, i->count, i))) > + if (unlikely(i->count != 0 && !copy_nofault(perf_entry + 1, i->count, i))) > goto discard; > > if (!list_empty(&user->validators) && > -- > 2.25.1
