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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 80999C433E1 for ; Fri, 3 Jul 2020 06:04:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E3B2208FE for ; Fri, 3 Jul 2020 06:04:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593756284; bh=ktuG9czb+58BbK8kRYL68lYjCdzJrusDhSKUz53p4A4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=rRDZFoNk0I4olatTJQ+0t/zq5DGhAXu83fymLkXVzNBPQH/IwUqgkwqy0g5GuRM0r +5Ump3YFlE8YpbKxLDA4a9RdJJdspRxyS0PnfPUzUurdAQAIcl3piaHJXCJJ5aJb1a YX6uSFMxQne89/J8V4aE+v6+P0MCuHbtFVQiEKC4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726183AbgGCGEn (ORCPT ); Fri, 3 Jul 2020 02:04:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:60530 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725648AbgGCGEm (ORCPT ); Fri, 3 Jul 2020 02:04:42 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 AE71A2075D; Fri, 3 Jul 2020 06:04:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593756282; bh=ktuG9czb+58BbK8kRYL68lYjCdzJrusDhSKUz53p4A4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LxEKRXVkGE4cuKlchDNeSGwI6mfVsfD9qgCi86Lx9akoCLQz3XnI5iiGFE0Oj5tEH +6rlrYnnuxWIPLcGqfEwvzlZeGxpIrczXs84fzQ588H5x3rqo4IwEX3Sr6x1Yhi8Ol T7BWukASauTr0EjDo+bxgvLKQ59994XBMbeXjfpo= Date: Fri, 3 Jul 2020 08:04:39 +0200 From: Greg Kroah-Hartman To: Pavel Machek Cc: Sasha Levin , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Masami Hiramatsu , Tom Zanussi , Steven Rostedt Subject: Re: [PATCH 4.19 119/131] tracing: Fix event trigger to accept redundant spaces Message-ID: <20200703060439.GB6344@kroah.com> References: <20200629153502.2494656-1-sashal@kernel.org> <20200629153502.2494656-120-sashal@kernel.org> <20200702211728.GD5787@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200702211728.GD5787@amd> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 02, 2020 at 11:17:28PM +0200, Pavel Machek wrote: > Hi! > > > commit 6784beada631800f2c5afd567e5628c843362cee upstream. > > > > Fix the event trigger to accept redundant spaces in > > the trigger input. > > > > For example, these return -EINVAL > > > > echo " traceon" > events/ftrace/print/trigger > > echo "traceon if common_pid == 0" > events/ftrace/print/trigger > > echo "disable_event:kmem:kmalloc " > events/ftrace/print/trigger > > > > But these are hard to find what is wrong. > > > > To fix this issue, use skip_spaces() to remove spaces > > in front of actual tokens, and set NULL if there is no > > token. > > For the record, I'm not fan of this one. It is ABI change, not a > bugfix. > > Yes, it makes kernel interface "easier to use". It also changes > interface in the middle of stable series, and if people start relying > on new interface and start putting extra spaces, they'll get nasty > surprise when they move code to the older kernel. If an interface changes anywhere that breaks userspace, it needs to be not done, stable kernels are not an issue here or not. Does this do that? It looks to me that this actually fixes things instead. thanks, greg k-h