Since the commit mentioned below __xdp_reg_mem_model() can return a NULL pointer. This pointer is dereferenced in trace_mem_connect() which leads to segfault. The trace points (mem_connect + mem_disconnect) were put in place to pair connect/disconnect using the IDs. The ID is only assigned if __xdp_reg_mem_model() does not return NULL. That connect trace point is of no use if there is no ID. Skip that connect trace point if xdp_alloc is NULL. [ Toke Høiland-Jørgensen delivered the reasoning for skipping the trace point ] Fixes: 4a48ef70b93b8 ("xdp: Allow registering memory model without rxq reference") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Acked-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> --- v2…v3: - Use trace_mem_connect_enabled() as suggested by Steven Rostedt. v1…v2: - Instead letting the trace point deal with a NULL pointer, skip the trace point. net/core/xdp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/core/xdp.c b/net/core/xdp.c index 7aba355049862..73fae16264e10 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -357,7 +357,8 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, if (IS_ERR(xdp_alloc)) return PTR_ERR(xdp_alloc); - trace_mem_connect(xdp_alloc, xdp_rxq); + if (trace_mem_connect_enabled() && xdp_alloc) + trace_mem_connect(xdp_alloc, xdp_rxq); return 0; } -- 2.35.1