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 9A8B7C433E4 for ; Mon, 13 Jul 2020 15:52:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 32C602076D for ; Mon, 13 Jul 2020 15:52:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="wl1NZRBG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 32C602076D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B02C78D000B; Mon, 13 Jul 2020 11:52:24 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AB3488D0002; Mon, 13 Jul 2020 11:52:24 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 97AFD8D000B; Mon, 13 Jul 2020 11:52:24 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0184.hostedemail.com [216.40.44.184]) by kanga.kvack.org (Postfix) with ESMTP id 82F608D0002 for ; Mon, 13 Jul 2020 11:52:24 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id EE91C40C7 for ; Mon, 13 Jul 2020 15:52:23 +0000 (UTC) X-FDA: 77033494566.10.guide40_6006e7626ee9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin10.hostedemail.com (Postfix) with ESMTP id BB39116A069 for ; Mon, 13 Jul 2020 15:52:23 +0000 (UTC) X-HE-Tag: guide40_6006e7626ee9 X-Filterd-Recvd-Size: 4336 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf14.hostedemail.com (Postfix) with ESMTP for ; Mon, 13 Jul 2020 15:52:23 +0000 (UTC) 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: X-Rspamd-Queue-Id: BB39116A069 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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