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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 8BBA4C3F2D2 for ; Fri, 28 Feb 2020 19:54:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E540246B4 for ; Fri, 28 Feb 2020 19:54:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582919648; bh=yFa9GTusWGP9MI5rVwDvWIvMEuL11F9VB9eTfxoriBM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=ewqdMin8FO6o2N9a1/6mMI4/5tsnkjlnw+Baz31sZjh41ykvVaq60lNIxETAnlQau NcQ4teVK4rsvPnqjQ8MmCULHXP3Gbdy2HU7pkMqewGs2c+HMnKJlhys4vMwZz1I8k1 /6fYJdEapm6gxHfAn/U6ERUpkLMAKhTLtbKyRDaA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726925AbgB1TyH (ORCPT ); Fri, 28 Feb 2020 14:54:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:59750 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726838AbgB1TyG (ORCPT ); Fri, 28 Feb 2020 14:54:06 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (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 57062246A3; Fri, 28 Feb 2020 19:54:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582919646; bh=yFa9GTusWGP9MI5rVwDvWIvMEuL11F9VB9eTfxoriBM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=B7Z/yodHUB8jE1bVpRXAyJta0eKioEPjfCw0GF3NCMjGhDN1gn5BpcyeV84YQmLg2 PswXKPBgjSBEMksGGcEuSgtvpKJQgXX5ALZt+ywZjnvujiZTKUxDG8tYkw3UkRQYXx kzjfo8K+yVPrQsMIwDCyCNsChFGVJ1In0k2PcIrg= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1j7li0-008qC3-Io; Fri, 28 Feb 2020 19:54:04 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 28 Feb 2020 19:54:04 +0000 From: Marc Zyngier To: Joe Jin Cc: Thomas Gleixner , linux-kernel@vger.kernel.org Subject: Re: [PATCH] genirq/debugfs: add new config option for trigger interrupt from userspace In-Reply-To: References: <44a7007d-9624-8ac7-e0ab-fab8bdd39848@oracle.com> <006a08b8bfb991853ede8c9d1e29d6a7@kernel.org> Message-ID: X-Sender: maz@kernel.org User-Agent: Roundcube Webmail/1.3.10 X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: joe.jin@oracle.com, tglx@linutronix.de, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-02-28 19:13, Joe Jin wrote: > Hi Marc, > > Thanks for your reply. > > On 2/28/20 8:37 AM, Marc Zyngier wrote: >> On 2020-02-28 05:42, Joe Jin wrote: >>> commit 536e2e34bd00 ("genirq/debugfs: Triggering of interrupts from >>> userspace") is allowed developer inject interrupts via irq debugfs, >>> which >>> is very useful during development phase, but on a production system, >>> this >>> is very dangerous, add new config option, developers can enable it as >>> needed instead of enabling it by default when irq debugfs is enabled. >> >> I don't really mind the patch (although it could be more elegant), but >> in >> general I object to most debugfs options being set on a production >> kernel. >> There is way too much information in most debugfs backends to be >> comfortable >> with it, and you can find things like page table dumps, for example... > > We should not enable any debug option on production system, actual > customer > want to resize their BM or VM, cpu offline may lead system not works > properly, > and if we knew more details of IRQ info it will be very help to > identify > if it caused by IRQ/vectors, this is the motivation of we want to > enable it > on production kernel. If something doesn't work properly, then you are still debugging, AFAICT. M. -- Jazz is not dead. It just smells funny...