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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 51060C433EF for ; Sat, 19 Feb 2022 00:55:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240942AbiBSA4H (ORCPT ); Fri, 18 Feb 2022 19:56:07 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:39854 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240741AbiBSAzg (ORCPT ); Fri, 18 Feb 2022 19:55:36 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 44D78279905 for ; Fri, 18 Feb 2022 16:55:16 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E9A63B8240F for ; Sat, 19 Feb 2022 00:55:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9051CC340ED; Sat, 19 Feb 2022 00:55:13 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.95) (envelope-from ) id 1nLE1o-0051XQ-OK; Fri, 18 Feb 2022 19:55:12 -0500 Message-ID: <20220219005512.589693373@goodmis.org> User-Agent: quilt/0.66 Date: Fri, 18 Feb 2022 19:54:32 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Tom Zanussi Subject: [for-next][PATCH 02/16] tracing: Remove size restriction on hist trigger cmd error logging References: <20220219005430.848118506@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tom Zanussi Currently, hist trigger command error strings are restricted to a length of MAX_FILTER_STR_VAL (256), which is too short for some commands already seen in the wild (with cmd strings longer than that showing up truncated in err_log). Remove the restriction so that no hist trigger command error string is ever truncated. Link: https://lkml.kernel.org/r/0f9d46407222eaf6632cd3b417bc50a11f401b71.1643399022.git.zanussi@kernel.org Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace_events_hist.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index ada87bfb5bb8..5e8970624bce 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -727,11 +727,16 @@ static struct track_data *track_data_alloc(unsigned int key_len, return data; } -static char last_cmd[MAX_FILTER_STR_VAL]; +#define HIST_PREFIX "hist:" + +static char *last_cmd; static char last_cmd_loc[MAX_FILTER_STR_VAL]; static int errpos(char *str) { + if (!str || !last_cmd) + return 0; + return err_pos(last_cmd, str); } @@ -739,12 +744,19 @@ static void last_cmd_set(struct trace_event_file *file, char *str) { const char *system = NULL, *name = NULL; struct trace_event_call *call; + int len = 0; if (!str) return; - strcpy(last_cmd, "hist:"); - strncat(last_cmd, str, MAX_FILTER_STR_VAL - 1 - sizeof("hist:")); + len += sizeof(HIST_PREFIX) + strlen(str) + 1; + kfree(last_cmd); + last_cmd = kzalloc(len, GFP_KERNEL); + if (!last_cmd) + return; + + strcpy(last_cmd, HIST_PREFIX); + strncat(last_cmd, str, len - sizeof(HIST_PREFIX)); if (file) { call = file->event_call; @@ -757,18 +769,22 @@ static void last_cmd_set(struct trace_event_file *file, char *str) } if (system) - snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, "hist:%s:%s", system, name); + snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name); } -static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos) +static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos) { + if (!last_cmd) + return; + tracing_log_err(tr, last_cmd_loc, last_cmd, err_text, err_type, err_pos); } static void hist_err_clear(void) { - last_cmd[0] = '\0'; + if (last_cmd) + last_cmd[0] = '\0'; last_cmd_loc[0] = '\0'; } @@ -5610,7 +5626,7 @@ static int event_hist_trigger_print(struct seq_file *m, bool have_var = false; unsigned int i; - seq_puts(m, "hist:"); + seq_puts(m, HIST_PREFIX); if (data->name) seq_printf(m, "%s:", data->name); -- 2.34.1