From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5187C2F27; Wed, 2 Feb 2022 18:28:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643826494; x=1675362494; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=B+ybzEvcSkWC9hIHFoztcZ1HBSXahf3cZDN+xuaqJpk=; b=WcScca6ENRNnJRxg7r7dYzVQT/6RxD8pPlDxp9HJ6gfid6Bcq3KQRx4B mi9xBMmNXTQJ+H5VpFxeOvIr89YQt0AMzLMzq5GK6XSBUB2xRzzcVr3hK 5hbgcAhgqJbIrOimimMK46yOQB47rz3jTJ4fvMQCwzZT/voz9Y6ks7vbU VI4Cs7jgsyGF7c8HlH17Z3cEkuqpcLc4uBi09Q/jivVjlaHBqVUeXk+lU k61y0y4zxCDEUSml7muvyKaO+xeJq8mEBKe9fhPHiIf+u/O9zYUopL/8n B1R2ROwWsFGnTLe8Y2KFjgbpDh/eo9hiqwxQDEgGp/55XEkK6hJw/h1U/ w==; X-IronPort-AV: E=McAfee;i="6200,9189,10246"; a="246825489" X-IronPort-AV: E=Sophos;i="5.88,337,1635231600"; d="scan'208";a="246825489" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Feb 2022 10:28:13 -0800 X-IronPort-AV: E=Sophos;i="5.88,337,1635231600"; d="scan'208";a="534953966" Received: from svenur-mobl2.amr.corp.intel.com (HELO intel.com) ([10.252.133.34]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Feb 2022 10:28:12 -0800 Date: Wed, 2 Feb 2022 10:28:11 -0800 From: Ben Widawsky To: Dan Williams Cc: linux-cxl@vger.kernel.org, patches@lists.linux.dev, Alison Schofield , Ira Weiny , Jonathan Cameron , Vishal Verma , Bjorn Helgaas , Linux NVDIMM , Linux PCI Subject: Re: [PATCH v3 01/14] cxl/region: Add region creation ABI Message-ID: <20220202182811.ivupsaeogyiwl5so@intel.com> References: <20220128002707.391076-1-ben.widawsky@intel.com> <20220128002707.391076-2-ben.widawsky@intel.com> <20220202182604.oangkxomx3npmobl@intel.com> Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220202182604.oangkxomx3npmobl@intel.com> On 22-02-02 10:26:06, Ben Widawsky wrote: > On 22-01-28 10:59:26, Dan Williams wrote: > > On Fri, Jan 28, 2022 at 10:14 AM Dan Williams wrote: > > [..] > > > Here is that put_device() I was expecting, that kfree() earlier was a > > > double-free it seems. > > > > > > Also, I would have expected a devm action to remove this. Something like: > > > > > > struct cxl_port *port = to_cxl_port(cxld->dev.parent); > > > > > > cxl_device_lock(&port->dev); > > > if (port->dev.driver) > > > devm_cxl_add_region(port->uport, cxld, id); > > I assume you mean devm_cxl_delete_region(), yes? > > > > else > > > rc = -ENXIO; > > > cxl_device_unlock(&port->dev); > > > > > > ...then no matter what you know the region will be unregistered when > > > the root port goes away. > > > > ...actually, the lock and ->dev.driver check here are not needed > > because this attribute is only registered while the cxl_acpi driver is > > bound. So, it is safe to assume this is protected as decoder remove > > synchronizes against active sysfs users. > > I'm somewhat confused when you say devm action to remove this. The current auto > region deletion happens when the ->release() is called. Are you suggesting when > the root decoder is removed I delete the regions at that point? Hmm. I went back and looked and I had changed this functionality at some point... So forget I said that, it isn't how it's working currently. But the question remains, are you suggesting I delete in the root decoder unregistration?