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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 30F7BC282DD for ; Tue, 7 Jan 2020 21:38:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 035B52073D for ; Tue, 7 Jan 2020 21:38:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Wt5a7oKN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726210AbgAGVh6 (ORCPT ); Tue, 7 Jan 2020 16:37:58 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:57912 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727303AbgAGVhz (ORCPT ); Tue, 7 Jan 2020 16:37:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1578433074; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xSFxCL3k8Q6kQpuVjvodBV8GghU6vTCrTI5PKdnHV9s=; b=Wt5a7oKNSeQ7q2NZXLSWyWmlmQcm9qS9iiBWIufgGNPPUklqnugcdqpILQOpurTLGB5I7h /WYDZhj1ZrVFhCCCbfD2Z2E4lkTEUzNeL4lMTNmsvRb59oHAk9iZknos9SI5AyETIoPVBz 3EdNYNosLvVRdC9uPzUWzyHGy0AF3Kw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-326-fmmXZbPlOemJuWh2TJdqVw-1; Tue, 07 Jan 2020 16:37:49 -0500 X-MC-Unique: fmmXZbPlOemJuWh2TJdqVw-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E3463107ACC7; Tue, 7 Jan 2020 21:37:47 +0000 (UTC) Received: from emilne (unknown [10.18.25.205]) by smtp.corp.redhat.com (Postfix) with ESMTP id 455638208E; Tue, 7 Jan 2020 21:37:44 +0000 (UTC) Message-ID: <1eb9d796f81fffbb0bfe90bff8460bcda34cb04d.camel@redhat.com> Subject: Re: [resend v1 5/5] drivers/scsi/sd.c: Convert to use disk_set_capacity From: "Ewan D. Milne" To: "Martin K. Petersen" , James Bottomley Cc: axboe@kernel.dk, Chaitanya.Kulkarni@wdc.com, mst@redhat.com, linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, ssomesh@amazon.com, Balbir Singh , hch@lst.de Date: Tue, 07 Jan 2020 16:37:43 -0500 In-Reply-To: References: <20200102075315.22652-1-sblbir@amazon.com> <20200102075315.22652-6-sblbir@amazon.com> <1578369479.3251.31.camel@linux.ibm.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon, 2020-01-06 at 23:39 -0500, Martin K. Petersen wrote: > James, > > > > We already emit an SDEV_EVT_CAPACITY_CHANGE_REPORTED event if device > > > capacity changes. However, this event does not automatically cause > > > revalidation. > > > > Which I seem to remember was a deliberate choice: some change > > capacities occur because the path goes passive and default values get > > installed. > > Yep, it's very tricky territory. > Yes, there are some storage arrays that refuse a READ CAPACITY command in certain ALUA states so you can't get the new capacity anyway. It might be nice to improve this, though, there are some cases now where we set the capacity to zero when we revalidate and can't get the value. -Ewan