From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0CCDDC2D0D2 for ; Sat, 21 Dec 2019 21:11:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE1BD206EC for ; Sat, 21 Dec 2019 21:11:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727492AbfLUVLk (ORCPT ); Sat, 21 Dec 2019 16:11:40 -0500 Received: from mail.kernel.org ([198.145.29.99]:36860 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727412AbfLUVLf (ORCPT ); Sat, 21 Dec 2019 16:11:35 -0500 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id AC8272166E; Sat, 21 Dec 2019 21:11:34 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.92.3) (envelope-from ) id 1iim29-000o3L-QZ; Sat, 21 Dec 2019 16:11:33 -0500 Message-Id: <20191221211133.694338753@goodmis.org> User-Agent: quilt/0.65 Date: Sat, 21 Dec 2019 16:11:11 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , stable@vger.kernel.org, Tom Zanussi , Sven Schnelle Subject: [for-linus][PATCH 5/5] tracing: Fix endianness bug in histogram trigger References: <20191221211106.338673631@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sven Schnelle At least on PA-RISC and s390 synthetic histogram triggers are failing selftests because trace_event_raw_event_synth() always writes a 64 bit values, but the reader expects a field->size sized value. On little endian machines this doesn't hurt, but on big endian this makes the reader always read zero values. Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-4-svens@linux.ibm.com Cc: stable@vger.kernel.org Fixes: 4b147936fa509 ("tracing: Add support for 'synthetic' events") Acked-by: Tom Zanussi Signed-off-by: Sven Schnelle Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events_hist.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index f49d1a36d3ae..f62de5f43e79 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -911,7 +911,26 @@ static notrace void trace_event_raw_event_synth(void *__data, strscpy(str_field, str_val, STR_VAR_LEN_MAX); n_u64 += STR_VAR_LEN_MAX / sizeof(u64); } else { - entry->fields[n_u64] = var_ref_vals[var_ref_idx + i]; + struct synth_field *field = event->fields[i]; + u64 val = var_ref_vals[var_ref_idx + i]; + + switch (field->size) { + case 1: + *(u8 *)&entry->fields[n_u64] = (u8)val; + break; + + case 2: + *(u16 *)&entry->fields[n_u64] = (u16)val; + break; + + case 4: + *(u32 *)&entry->fields[n_u64] = (u32)val; + break; + + default: + entry->fields[n_u64] = val; + break; + } n_u64++; } } -- 2.24.0