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Mon, 12 Dec 2022 22:23:46 -0800 (PST) Received: from redhat.com ([2.52.138.183]) by smtp.gmail.com with ESMTPSA id q4-20020adffec4000000b00241c6729c2bsm10574835wrs.26.2022.12.12.22.23.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Dec 2022 22:23:46 -0800 (PST) Date: Tue, 13 Dec 2022 01:23:42 -0500 From: "Michael S. Tsirkin" To: Chaitanya Kulkarni Message-ID: <20221213001034-mutt-send-email-mst@kernel.org> References: <20221205162035.2261037-1-alvaro.karsz@solid-run.com> <20221207052001-mutt-send-email-mst@kernel.org> <20221207152116-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Subject: Re: [dm-devel] [PATCH v3] virtio_blk: add VIRTIO_BLK_F_LIFETIME feature support X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jens Axboe , "linux-block@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "linux-nvme@lists.infradead.org" , "virtualization@lists.linux-foundation.org" , Christoph Hellwig , "dm-devel@redhat.com" , Stefan Hajnoczi , Paolo Bonzini Errors-To: dm-devel-bounces@redhat.com Sender: "dm-devel" X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Tue, Dec 13, 2022 at 04:58:47AM +0000, Chaitanya Kulkarni wrote: > Michael, > > On 12/7/22 12:28, Michael S. Tsirkin wrote: > > On Wed, Dec 07, 2022 at 08:31:28AM -0800, Christoph Hellwig wrote: > >> On Wed, Dec 07, 2022 at 05:21:48AM -0500, Michael S. Tsirkin wrote: > >>> Christoph you acked the spec patch adding this to virtio blk: > >>> > >>> Still not a fan of the encoding, but at least it is properly documented > >>> now: > >>> > >>> Acked-by: Christoph Hellwig > >>> > >>> Did you change your mind then? Or do you prefer a different encoding for > >>> the ioctl then? could you help sugesting what kind? > >> > >> Well, it is good enough documented for a spec. I don't think it is > >> a useful feature for Linux where virtio-blk is our minimum viable > >> paravirtualized block driver. > > > > No idea what this means, sorry. Now that's in the spec I expect (some) > > devices to implement it and if they do I see no reason not to expose the > > data to userspace. > > > > Even if any device implements is it can always use passthru commands. > See below for more info... > > > Alvaro could you pls explain the use-case? Christoph has doubts that > > it's useful. Do you have a device implementing this? > > > > From what I know, virtio-blk should be kept minimal and should not > add any storage specific IOCTLs or features that will end up loosing > its generic nature. > > The IOCTL we are trying to add is Flash storage specific which > goes against the nature of generic storage and makes it non-generic. > In case we approve this it will open the door for non-generic > code/IOCTL in the virtio-blk and that needs to be avoided. Wrt these fields that horse has bolted, it's in the spec. > For any storage specific features or IOCTL (flash/HDD) it should > be using it's own frontend such as virtio-scsi or e.g. nvme and > not virtio-blk. > > Hope this helps. > > -ck I don't understand what you are suggesting, sorry. It's a hardware device. It can't just "switch to a different frontend". -- MST -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 051A7C4332F for ; Tue, 13 Dec 2022 06:25:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229975AbiLMGZp (ORCPT ); Tue, 13 Dec 2022 01:25:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234550AbiLMGZd (ORCPT ); Tue, 13 Dec 2022 01:25:33 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 961AC1EEF5 for ; Mon, 12 Dec 2022 22:23:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1670912629; 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: in-reply-to:in-reply-to:references:references; bh=zdosc0+4UprGU1f9HW8VSDzkH/4Gm3wZqjmhjmwHaoc=; b=TEUcTCe6Dy4qlCXRrmfnFldFoBtD1Emh8sDSHp9/bdvFgHouBzdqlGwofAYhvvKfaASv1C DUfyNSIT5k6lWEvE3yrO33silByTchh5GdpcxVktbtfqPa9/yITZkTbkHnd8/rzgZloCuV vl/rnrq+IT6Y3JswMxCqsc2FqXyHORI= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-564-KlHKr9wePn6CMHKtQS1SBg-1; Tue, 13 Dec 2022 01:23:48 -0500 X-MC-Unique: KlHKr9wePn6CMHKtQS1SBg-1 Received: by mail-wm1-f72.google.com with SMTP id n8-20020a05600c294800b003d1cc68889dso2571645wmd.7 for ; Mon, 12 Dec 2022 22:23:48 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=zdosc0+4UprGU1f9HW8VSDzkH/4Gm3wZqjmhjmwHaoc=; b=PFg3Pk6DylPPxwHyE7WeNJ6LajHg0BVSH/r4eirQlEVVjy4gvynHHtD3z9A1CaMtuQ N6f5TgU82rYvDV6++kLe7oTN/X4CqZjsJryN2CKt5f6uHItFRX/wXpQGwTkphngCRoxJ sgy4hsHIBjSB+VmYOzE+ejMC1Ong+PHc8TU8j8ERfsjcyY2z3sobswdItZvoijSPAM5J Jv6nkkbzxUwppu58kzkDznyt1hiCcaS+rHgLZKM5LEU3YaMfPLfaX1HffNcZD/9D5fS/ Xls7+Hr6imfaSYUyOWAyLrLrGjPg4QzVSfkBzNlug52SC/PCBSgRN0Nq5kEqm2+6iona AhhA== X-Gm-Message-State: ANoB5pnQKK+EnIL1sGnebv3r4MWgFaJWsjAjFdMGlq0gruYKx+CiZ0Pj 8eTUnNNWhYRs8BhZVPxqmKbQO+BSaWALhCYC0GrVo3ZsO+vyASU/RoJ4jo4s175pttC02+eUMoE gGTXHjJlNbYj7RN9v/GRIRvc= X-Received: by 2002:a5d:4b0b:0:b0:241:f8b6:9693 with SMTP id v11-20020a5d4b0b000000b00241f8b69693mr10657855wrq.37.1670912627218; Mon, 12 Dec 2022 22:23:47 -0800 (PST) X-Google-Smtp-Source: AA0mqf4I9L5F8Y2mNHOKhXS0GG3uRTSVP0X4b9ULK97I3031/HbGTKYGoQr9e4elbaLdVkvuI9TpMQ== X-Received: by 2002:a5d:4b0b:0:b0:241:f8b6:9693 with SMTP id v11-20020a5d4b0b000000b00241f8b69693mr10657848wrq.37.1670912626982; Mon, 12 Dec 2022 22:23:46 -0800 (PST) Received: from redhat.com ([2.52.138.183]) by smtp.gmail.com with ESMTPSA id q4-20020adffec4000000b00241c6729c2bsm10574835wrs.26.2022.12.12.22.23.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Dec 2022 22:23:46 -0800 (PST) Date: Tue, 13 Dec 2022 01:23:42 -0500 From: "Michael S. Tsirkin" To: Chaitanya Kulkarni Cc: Jens Axboe , Christoph Hellwig , "linux-scsi@vger.kernel.org" , "linux-nvme@lists.infradead.org" , "virtualization@lists.linux-foundation.org" , "linux-block@vger.kernel.org" , "dm-devel@redhat.com" , Stefan Hajnoczi , Paolo Bonzini Subject: Re: [PATCH v3] virtio_blk: add VIRTIO_BLK_F_LIFETIME feature support Message-ID: <20221213001034-mutt-send-email-mst@kernel.org> References: <20221205162035.2261037-1-alvaro.karsz@solid-run.com> <20221207052001-mutt-send-email-mst@kernel.org> <20221207152116-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Tue, Dec 13, 2022 at 04:58:47AM +0000, Chaitanya Kulkarni wrote: > Michael, > > On 12/7/22 12:28, Michael S. Tsirkin wrote: > > On Wed, Dec 07, 2022 at 08:31:28AM -0800, Christoph Hellwig wrote: > >> On Wed, Dec 07, 2022 at 05:21:48AM -0500, Michael S. Tsirkin wrote: > >>> Christoph you acked the spec patch adding this to virtio blk: > >>> > >>> Still not a fan of the encoding, but at least it is properly documented > >>> now: > >>> > >>> Acked-by: Christoph Hellwig > >>> > >>> Did you change your mind then? Or do you prefer a different encoding for > >>> the ioctl then? could you help sugesting what kind? > >> > >> Well, it is good enough documented for a spec. I don't think it is > >> a useful feature for Linux where virtio-blk is our minimum viable > >> paravirtualized block driver. > > > > No idea what this means, sorry. Now that's in the spec I expect (some) > > devices to implement it and if they do I see no reason not to expose the > > data to userspace. > > > > Even if any device implements is it can always use passthru commands. > See below for more info... > > > Alvaro could you pls explain the use-case? Christoph has doubts that > > it's useful. Do you have a device implementing this? > > > > From what I know, virtio-blk should be kept minimal and should not > add any storage specific IOCTLs or features that will end up loosing > its generic nature. > > The IOCTL we are trying to add is Flash storage specific which > goes against the nature of generic storage and makes it non-generic. > In case we approve this it will open the door for non-generic > code/IOCTL in the virtio-blk and that needs to be avoided. Wrt these fields that horse has bolted, it's in the spec. > For any storage specific features or IOCTL (flash/HDD) it should > be using it's own frontend such as virtio-scsi or e.g. nvme and > not virtio-blk. > > Hope this helps. > > -ck I don't understand what you are suggesting, sorry. It's a hardware device. It can't just "switch to a different frontend". -- MST 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 Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BADA9C4332F for ; Tue, 13 Dec 2022 06:23:55 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 41D6081DCB; Tue, 13 Dec 2022 06:23:55 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org 41D6081DCB Authentication-Results: smtp1.osuosl.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=TEUcTCe6 X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id WbhlDzs2H7oU; 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Tsirkin" To: Chaitanya Kulkarni Subject: Re: [PATCH v3] virtio_blk: add VIRTIO_BLK_F_LIFETIME feature support Message-ID: <20221213001034-mutt-send-email-mst@kernel.org> References: <20221205162035.2261037-1-alvaro.karsz@solid-run.com> <20221207052001-mutt-send-email-mst@kernel.org> <20221207152116-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Cc: Jens Axboe , "linux-block@vger.kernel.org" , "linux-scsi@vger.kernel.org" , "linux-nvme@lists.infradead.org" , "virtualization@lists.linux-foundation.org" , Christoph Hellwig , "dm-devel@redhat.com" , Stefan Hajnoczi , Paolo Bonzini X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Tue, Dec 13, 2022 at 04:58:47AM +0000, Chaitanya Kulkarni wrote: > Michael, > > On 12/7/22 12:28, Michael S. Tsirkin wrote: > > On Wed, Dec 07, 2022 at 08:31:28AM -0800, Christoph Hellwig wrote: > >> On Wed, Dec 07, 2022 at 05:21:48AM -0500, Michael S. Tsirkin wrote: > >>> Christoph you acked the spec patch adding this to virtio blk: > >>> > >>> Still not a fan of the encoding, but at least it is properly documented > >>> now: > >>> > >>> Acked-by: Christoph Hellwig > >>> > >>> Did you change your mind then? Or do you prefer a different encoding for > >>> the ioctl then? could you help sugesting what kind? > >> > >> Well, it is good enough documented for a spec. I don't think it is > >> a useful feature for Linux where virtio-blk is our minimum viable > >> paravirtualized block driver. > > > > No idea what this means, sorry. Now that's in the spec I expect (some) > > devices to implement it and if they do I see no reason not to expose the > > data to userspace. > > > > Even if any device implements is it can always use passthru commands. > See below for more info... > > > Alvaro could you pls explain the use-case? Christoph has doubts that > > it's useful. Do you have a device implementing this? > > > > From what I know, virtio-blk should be kept minimal and should not > add any storage specific IOCTLs or features that will end up loosing > its generic nature. > > The IOCTL we are trying to add is Flash storage specific which > goes against the nature of generic storage and makes it non-generic. > In case we approve this it will open the door for non-generic > code/IOCTL in the virtio-blk and that needs to be avoided. Wrt these fields that horse has bolted, it's in the spec. > For any storage specific features or IOCTL (flash/HDD) it should > be using it's own frontend such as virtio-scsi or e.g. nvme and > not virtio-blk. > > Hope this helps. > > -ck I don't understand what you are suggesting, sorry. It's a hardware device. It can't just "switch to a different frontend". -- MST _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization