From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 D72917482; Thu, 20 Mar 2025 05:48:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742449696; cv=none; b=SENvlyNtyHns6+BodpfkHSkM09KpvEx/vu091ojYwthDCwfmR33Ynw/kctJ7RwIIgVS1EGtH3puBujdJbO8KAQFJxg9KqOLlq9he7dR5/OlRq2r2EG/d+D2lEdKj/JwIMqtqFmg0EXgYFniNMfkRb+Z7sXFuuYKH3iLXGHntEms= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742449696; c=relaxed/simple; bh=ZCqa1kK4yN7nk/NG8bkHiIXdA+DyndLxxAyigDwUJbk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=E6VYi2F4WA2WyjIVoszfA1LfXxKZqgz0uVQPzj6ZWfemypcNTtTWJX+fNTu7TM9GpC1jeNnab2hxGkoMbbUSYu2Cm29OaR3eBes1xXMBILwwSILEPXPyQ6xv2UhYg46kWMrJEgZK40DEA2vVQCC3UKnm3Onql+7ge9Xc4eG3ge0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=FevDVPUt; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="FevDVPUt" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=whmPEYHG6N1H8UlgtSGjiPfpFSDvL0exFGvh42fP/5g=; b=FevDVPUt3SbAei9b89H4qsOjgq +CAmjV0Pw3nprvaf5FRhHJQyRNhvIKAW0Tnev6dtJD/er8x3hRC+t3i1JQjNFvoSsmMuWwLkrtVbm xmsstUnYCIZDSbY0iZnkyqH/AsRno2o6Fx9dK7qoEqBQdRoSWT+I47eRXq+e5FQq/r0p4QVFUx7w5 lwIN8FNswBc7XiRuqRF7odDNVxi7CcRwdcGcc+/JgutaEl0tK8pXZeQDeFCRoru93RQgd3R4K4fUr EzS0heeUB9AD9+Aux7VDk2D3jKfmQF+oex2GEjb/s+zUixuQMJGKpwSer5GfM6kCTPeTQWHBxBI9z K5iFxIAA==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tv8lH-0000000BFMr-3Blz; Thu, 20 Mar 2025 05:48:11 +0000 Date: Wed, 19 Mar 2025 22:48:11 -0700 From: "hch@infradead.org" To: Kanchan Joshi Cc: "hch@infradead.org" , Qu Wenruo , Johannes Thumshirn , Theodore Ts'o , "lsf-pc@lists.linux-foundation.org" , "linux-btrfs@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "linux-nvme@lists.infradead.org" , "linux-block@vger.kernel.org" , "josef@toxicpanda.com" , "Martin K. Petersen" Subject: Re: [LSF/MM/BPF TOPIC] File system checksum offload Message-ID: References: <435cf6be-98e7-4b8b-ae42-e074091de991@samsung.com> Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <435cf6be-98e7-4b8b-ae42-e074091de991@samsung.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Wed, Mar 19, 2025 at 11:36:28PM +0530, Kanchan Joshi wrote: > I tried to describe that in the cover letter of the PoC: > https://lore.kernel.org/linux-btrfs/20250129140207.22718-1-joshi.k@samsung.com/ I don't think it does as people have pointed that out multiple times. Once you do checksums on the device they are not end to end, either in the T10 DIF definition or that of file system checksums. You leave a huge glaring gap in the protection envelope. So calling this "offload" is extremely dishonest and misleading.