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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 D4F7AC433E5 for ; Mon, 13 Jul 2020 15:52:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B7FE420773 for ; Mon, 13 Jul 2020 15:52:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594655545; bh=Hcixoq4GgPe0VCO4s6wUL8CqrZev3dIhKbWRkkOIrHc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=i86pdIF6t5XR7EFf2u2GxR3NJ8CJOLJl4JE6sUGYLOIFfTm1Dia2zoi8t1RB7znIg /hFEVMgNUh9vt6SoTYbdfh9fYTxt710/pWi0ca1m6iE6osmEoIcFv7XRH9HGVAT+HS nA9y62XJpi+sguwiegKRkW7Xn2wXqFFy8Ij3CVuA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730230AbgGMPwY (ORCPT ); Mon, 13 Jul 2020 11:52:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:45302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729593AbgGMPwX (ORCPT ); Mon, 13 Jul 2020 11:52:23 -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 BE59D20663; Mon, 13 Jul 2020 15:52:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594655542; bh=Hcixoq4GgPe0VCO4s6wUL8CqrZev3dIhKbWRkkOIrHc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=wl1NZRBGSi7cAVo8NztdIgBUgTQWNZEa4wL/fa93EpRcWtMHAVzi3ljykDEsPT7wY BSBmd7lLUo8a3wfMaWGkV93gEjLWGvbSbLjl6M/KlXZmAT7YEM7cfQHpIRkS5IlY1V vqCxN5LtjDOFOi7FWjtCOOK9yB+Z9NghG6kRstTs= Date: Mon, 13 Jul 2020 17:52:22 +0200 From: Greg Kroah-Hartman To: Dan Williams Cc: linux-nvdimm , "Rafael J. Wysocki" , Peter Zijlstra , Vishal L Verma , Dave Hansen , Ard Biesheuvel , Linux MM , Linux Kernel Mailing List , Linux ACPI , Christoph Hellwig , Joao Martins Subject: Re: [PATCH v2 17/22] drivers/base: Make device_find_child_by_name() compatible with sysfs inputs Message-ID: <20200713155222.GB267581@kroah.com> References: <159457116473.754248.7879464730875147365.stgit@dwillia2-desk3.amr.corp.intel.com> <159457125753.754248.6000936585361264069.stgit@dwillia2-desk3.amr.corp.intel.com> <20200712170945.GA194499@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Mon, Jul 13, 2020 at 08:39:43AM -0700, Dan Williams wrote: > On Sun, Jul 12, 2020 at 10:09 AM Greg Kroah-Hartman > wrote: > > > > On Sun, Jul 12, 2020 at 09:27:37AM -0700, Dan Williams wrote: > > > Use sysfs_streq() in device_find_child_by_name() to allow it to use a > > > sysfs input string that might contain a trailing newline. > > > > > > The other "device by name" interfaces, > > > {bus,driver,class}_find_device_by_name(), already account for sysfs > > > strings. > > > > > > Cc: Greg Kroah-Hartman > > > Cc: "Rafael J. Wysocki" > > > Signed-off-by: Dan Williams > > > --- > > > drivers/base/core.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/drivers/base/core.c b/drivers/base/core.c > > > index 67d39a90b45c..5d31b962c898 100644 > > > --- a/drivers/base/core.c > > > +++ b/drivers/base/core.c > > > @@ -3078,7 +3078,7 @@ struct device *device_find_child_by_name(struct device *parent, > > > > > > klist_iter_init(&parent->p->klist_children, &i); > > > while ((child = next_device(&i))) > > > - if (!strcmp(dev_name(child), name) && get_device(child)) > > > + if (sysfs_streq(dev_name(child), name) && get_device(child)) > > > > Who wants to call this function with a name passed from userspace? > > > > Not objecting to it, just curious... > > > > The series that incorporates this patch adds a partitioning mechanism > to "device-dax region" devices with an: > "echo 1 > regionX/create" to create a new partition / sub-instance > of a region, and... > "echo $devname > regionX/delete" to delete. Where $devname is > searched in the child devices of regionX to trigger device_del(). Shouldn't that be done in configfs, not sysfs? > This arrangement avoids one of the design mistakes of libnvdimm which > uses a sysfs attribute of the device to delete itself. Parent-device > triggered deletion rather than self-deletion avoids those locking > entanglements. Ugh, yeah, getting rid of that would be great, it's a mess. I think scsi still does that :( thanks, greg k-h