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 17CFA479872; Fri, 25 Sep 2026 09:10:48 +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=1790327452; cv=none; b=f56w2n4WMySNUu1bS6i9DRYIlrkOcv6ID7EqtcfpLX+MTm+qiEP1ptcfV50lRPJxpbK1G2NIdMgEzByULURJeBIJsFcDGdpdB6oRfJr4VIBNMFlgrfPK1gexj+SgtU1LGdw1zu7MH+vWZA3iHtiaywwkqUFPA/cNwxhKS0dS/AY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790327452; c=relaxed/simple; bh=ig5R/VvsS+9uNk4dBeTzMAiX1G+zzlE1Aub1dMxONKw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=iiH6rgkdQRBlHDJ+Nu9Gt019JkLN4M3kqEzDYZ6hHtt+IiqC5IrILqnMA19nv8pkjYGRBkGVxGM+f1rwHQM44w8UX/eNZIX6Ulj9pUtvacrzygOwcepglX4bojOveRdGYRRAbgkpMGHbb2EIZwph+mTiM5x0OXOA2HuISqf0Eq0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (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=EE6flcc4; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (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="EE6flcc4" 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=k3Xm1TdRHFUCZcaelTuIJRJooadtI6KrhUHTrvHal0M=; b=EE6flcc4ugeS+GxWJ6hOTp2M2F L4r0KqMGNNIrnJsTkWPB0TtOoBBJqhOBSXbwUmNoE1if8dysCzjkmZgRf45ZBDZk9i4mmmnqeDAmd xEawveXvAlpSyLW+MqvbOaVHcdDIYVClx4Lgt6KvYLQGEyqLNSypaBpr8PZK7jXmb+iJsrOiOwcQw D/zbnBao+gK9W2xKgE7MgXpCUG67TRRB05s0asT9b6486VISPDuKNDnvpb/e45Xv8nDAX694uK+XJ ziNgW6p51tsksaxVrdXzcLiWa3PvumpVn959yQYRE5ceqsCSNdDUpBwQluv/C7wb81f1G1ilGZOLJ uTMIPZXA==; Received: from hch by bombadil.infradead.org with local (Exim 4.99.1 #2 (Red Hat Linux)) id 1xA1x9-0000000Cyom-3fan; Fri, 25 Sep 2026 09:10:47 +0000 Date: Fri, 25 Sep 2026 02:10:47 -0700 From: Christoph Hellwig To: Leonid Ravich Cc: linux-crypto@vger.kernel.org, dm-devel@lists.linux.dev, herbert@gondor.apana.org.au, davem@davemloft.net, ebiggers@kernel.org, agk@redhat.com, snitzer@kernel.org, mpatocka@redhat.com, bmarzins@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 0/6] crypto: skcipher - multi-data-unit request splitting Message-ID: References: <20260924075846.28203-1-lravich@amazon.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260924075846.28203-1-lravich@amazon.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Thu, Sep 24, 2026 at 07:58:40AM +0000, Leonid Ravich wrote: > * No throughput *win* is claimed for software AES. The win is for > accelerators that amortise setup across units; the software split > exists so the interface works on every existing skcipher today and > goes quiet as algorithms gain CRYPTO_ALG_REQ_SEG. So what is the use case? So far all crypto driver we've seen have shown to be slower than cpu. Which one are you using that isn't? And if you have a genuinely useful one, should we have a proper interface to it that doesn't pay the scatterlist overhead to start with?