From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f176.google.com (mail-wi0-f176.google.com [209.85.212.176]) by kanga.kvack.org (Postfix) with ESMTP id C34756B0255 for ; Fri, 25 Sep 2015 14:49:18 -0400 (EDT) Received: by wicfx3 with SMTP id fx3so31002616wic.0 for ; Fri, 25 Sep 2015 11:49:18 -0700 (PDT) Received: from sipsolutions.net (s3.sipsolutions.net. [5.9.151.49]) by mx.google.com with ESMTPS id h8si6099731wiy.93.2015.09.25.11.49.17 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 25 Sep 2015 11:49:17 -0700 (PDT) Message-ID: <1443206945.2161.9.camel@sipsolutions.net> Subject: Re: [PATCH V4 1/2] ACPI / EC: Fix broken 64bit big-endian users of 'global_lock' From: Johannes Berg Date: Fri, 25 Sep 2015 20:49:05 +0200 In-Reply-To: <20150925184741.GF5951@linux> (sfid-20150925_204744_507179_F4A02CF2) References: <1443202945.2161.8.camel@sipsolutions.net> <20150925184741.GF5951@linux> (sfid-20150925_204744_507179_F4A02CF2) Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Viresh Kumar Cc: Greg Kroah-Hartman , linaro-kernel@lists.linaro.org, QCA ath9k Development , Intel Linux Wireless , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, linux-bluetooth@vger.kernel.org, iommu@lists.linux-foundation.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, linux-scsi@vger.kernel.org, linux-usb@vger.kernel.org, linux-edac@vger.kernel.org, linux-mm@kvack.org, alsa-devel@alsa-project.org > Rafael wrote: > > Actually, what about adding a local u32 variable, say val, here and > > doing > > > > > if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 > > > *)&first_ec->gpe)) > > > goto error; > > > if (!debugfs_create_bool("use_global_lock", 0444, > > > dev_dir, > > > - (u32 *)&first_ec->global_lock)) > > > + &first_ec->global_lock)) > > > > if (!debugfs_create_bool("use_global_lock", 0444, dev_dir, > > &val)) > > > > > goto error; > > > > first_ec->global_lock = val; > > > > And then you can turn val into bool just fine without changing the > > structure > > definition. Ok, then, but that means Rafael is completely wrong ... debugfs_create_bool() takes a *pointer* and it needs to be long-lived, it can't be on the stack. You also don't get a call when it changes. If you cannot change the struct definition then you must implement a debugfs file with its own read/write handlers. johannes -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org