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=-9.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 3476BC00A89 for ; Fri, 30 Oct 2020 07:57:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9A1622203 for ; Fri, 30 Oct 2020 07:57:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jgIk3kQq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726009AbgJ3H5Y (ORCPT ); Fri, 30 Oct 2020 03:57:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58258 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725956AbgJ3H5Y (ORCPT ); Fri, 30 Oct 2020 03:57:24 -0400 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26423C0613CF for ; Fri, 30 Oct 2020 00:57:24 -0700 (PDT) Received: by mail-pg1-x543.google.com with SMTP id o3so4506248pgr.11 for ; Fri, 30 Oct 2020 00:57:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=muDviu7LdHJg+SSfbczNSfqTYUnVpBS3s+/TDHUMTTw=; b=jgIk3kQqh6b5u8IMVHEg6AdHPuuke3JzirHkuNrOCCNKpeMK257DsLUoeFprqFh8Sz U+jweagDc8j2KnmzKdNbiv9B/CABxAw8RwQf2qsGFlB8ClYhnXz/4xTlrrK82ReaaXCY FyF8uYsKUx+Jsg+bWsN1VQ2OguKv7klzVR3JjwRuXzccW0KIzLmXlexdRAiUVePEvg44 K27mHToHsf5LnJ4r4314ZbAbDvHCgXXPKKlXuyksDHrUVcrenfOVSAOwGtxPk6Z7MgKb 3S6OHQKikdKPcJdpZz8QZYr2keQGpGGu2LplB/t9syqbHEhtrSYrpkZLRBg5RjmtI/cC djBg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=muDviu7LdHJg+SSfbczNSfqTYUnVpBS3s+/TDHUMTTw=; b=ATSVaHspAT28r4x35GLIj/gCpHTn9qgKwEIlB3q4L+gOeSeJgVdqXxzAmvq4JPFoc3 Vq1IhTgcmyPEC5vh1Hb8i5c/O9ZkrC18eWvk9nTnWEpG7PXisXHVNlXnTuWDn6jOwOQm S5ba3gZcb8D0GVilc1uSfmcCowb5x1SnbMM8rrwtdDZie2qvGGoiWJzE0xReUrKgu48D Cxyi3T4oLqY8nuYzFd9sfXuYsss73MaowiSTJyLA4RS+Mb2WTrDJKsegdnXkMazm01aO bl5gFKaYduppEDBvi9LS1ZJwysR42pPlaPldkOy2g/LXWi7lD6/nsMCfml5KfzhPFGup cuyw== X-Gm-Message-State: AOAM530m+YNeFDbEDJdtZVJSWsLa1RPUznsI591tv4015RGjTIw6eLJS oST2xb1A46xvg/4Z6790n98= X-Google-Smtp-Source: ABdhPJwwwhxE17Pk9mRvLaqPyLH8sC+zCszqpz892ul4ZfDWukCR0/BGEj8gA3lcqvZDIxcwXH53LQ== X-Received: by 2002:a62:6044:0:b029:151:1a04:895 with SMTP id u65-20020a6260440000b02901511a040895mr8132347pfb.34.1604044643581; Fri, 30 Oct 2020 00:57:23 -0700 (PDT) Received: from my--box ([103.98.79.70]) by smtp.gmail.com with ESMTPSA id j5sm2253085pjb.56.2020.10.30.00.57.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 30 Oct 2020 00:57:23 -0700 (PDT) Date: Fri, 30 Oct 2020 13:27:16 +0530 From: Deepak R Varma To: Greg KH Cc: outreachy-kernel@googlegroups.com, Alex Deucher , Christian =?iso-8859-1?Q?K=F6nig?= , David Airlie , Daniel Vetter , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, melissa.srw@gmail.com, daniel.vetter@ffwll.ch, mh12gx2825@gmail.com Subject: Re: [Outreachy kernel] [PATCH] drm/amdgpu: use DEFINE_DEBUGFS_ATTRIBUTE with debugfs_create_file_unsafe() Message-ID: <20201030075716.GA6976@my--box> References: <20201030032245.GA274478@my--box> <20201030071120.GA1493629@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201030071120.GA1493629@kroah.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 30, 2020 at 08:11:20AM +0100, Greg KH wrote: > On Fri, Oct 30, 2020 at 08:52:45AM +0530, Deepak R Varma wrote: > > Using DEFINE_DEBUGFS_ATTRIBUTE macro with debugfs_create_file_unsafe() > > function in place of the debugfs_create_file() function will make the > > file operation struct "reset" aware of the file's lifetime. Additional > > details here: https://lists.archive.carbon60.com/linux/kernel/2369498 > > > > Issue reported by Coccinelle script: > > scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci > > > > Signed-off-by: Deepak R Varma > > --- > > Please Note: This is a Outreachy project task patch. > > > > drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 20 ++++++++++---------- > > 1 file changed, 10 insertions(+), 10 deletions(-) > > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c > > index 2d125b8b15ee..f076b1ba7319 100644 > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c > > @@ -1551,29 +1551,29 @@ static int amdgpu_debugfs_sclk_set(void *data, u64 val) > > return 0; > > } > > > > -DEFINE_SIMPLE_ATTRIBUTE(fops_ib_preempt, NULL, > > - amdgpu_debugfs_ib_preempt, "%llu\n"); > > +DEFINE_DEBUGFS_ATTRIBUTE(fops_ib_preempt, NULL, > > + amdgpu_debugfs_ib_preempt, "%llu\n"); > > Are you sure this is ok? Do these devices need this additional > "protection"? Do they have the problem that these macros were written > for? > > Same for the other patches you just submitted here, I think you need to > somehow "prove" that these changes are necessary, checkpatch isn't able > to determine this all the time. Hi Greg, Based on my understanding, the current function debugfs_create_file() adds an overhead of lifetime managing proxy for such fop structs. This should be applicable to these set of drivers as well. Hence I think this change will be useful. I will wait for comments from other experts for driver specific consideration / behavior. Thanks, drv > > thanks, > > greg k-h