4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx> [ Upstream commit a15f7fc20389a8827d5859907568b201234d4b79 ] There are a small number of 'generic fields' (comm/COMM/cpu/CPU) that are found by trace_find_event_field() but are only meant for filtering. Specifically, they unlike normal fields, they have a size of 0 and thus wreak havoc when used as a histogram key. Exclude these (return -EINVAL) when used as histogram keys. Link: http://lkml.kernel.org/r/956154cbc3e8a4f0633d619b886c97f0f0edf7b4.1506105045.git.tom.zanussi@xxxxxxxxxxxxxxx Signed-off-by: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/trace/trace_events_hist.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -449,7 +449,7 @@ static int create_val_field(struct hist_ } field = trace_find_event_field(file->event_call, field_name); - if (!field) { + if (!field || !field->size) { ret = -EINVAL; goto out; } @@ -547,7 +547,7 @@ static int create_key_field(struct hist_ } field = trace_find_event_field(file->event_call, field_name); - if (!field) { + if (!field || !field->size) { ret = -EINVAL; goto out; }