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 C3AC6C636D4 for ; Mon, 30 Jan 2023 19:30:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237176AbjA3Tax (ORCPT ); Mon, 30 Jan 2023 14:30:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236733AbjA3Tat (ORCPT ); Mon, 30 Jan 2023 14:30:49 -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 2F8852687; Mon, 30 Jan 2023 11:30:46 -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 9F8C2B8165B; Mon, 30 Jan 2023 19:30:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B8B3AC433D2; Mon, 30 Jan 2023 19:30:42 +0000 (UTC) Date: Mon, 30 Jan 2023 14:30:41 -0500 From: Steven Rostedt To: Linyu Yuan Cc: Masami Hiramatsu , , Subject: Re: [PATCH v5] trace: acquire buffer from temparary trace sequence Message-ID: <20230130143041.713c4c7b@gandalf.local.home> In-Reply-To: <28cd9aca-1945-ceed-2756-162132d576ef@quicinc.com> References: <1675065249-23368-1-git-send-email-quic_linyyuan@quicinc.com> <28cd9aca-1945-ceed-2756-162132d576ef@quicinc.com> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 30 Jan 2023 21:14:01 +0800 Linyu Yuan wrote: > @Steven current design is not safe, as user still can write to buffer > which have no enough space. I'm assuming that it would never use more that DWC3_MSG_MAX, and that's set to 500. The size of the trace_seq() is 4096 (or PAGE_SIZE), I doubt it will ever be an issue. How do you think the user can still write more than enough? -- Steve > > do you think it is better to improve dwc3 trace in fast assign path ? >