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=-2.4 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,USER_AGENT_SANE_1 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 9A239C433DF for ; Wed, 10 Jun 2020 12:02:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7550D2074B for ; Wed, 10 Jun 2020 12:02:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="O0qKoJFb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728908AbgFJMC4 (ORCPT ); Wed, 10 Jun 2020 08:02:56 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:33769 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728753AbgFJMC4 (ORCPT ); Wed, 10 Jun 2020 08:02:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591790575; 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=TNsoGvRQNqCDBEQwQWNi/36A0peQaj7a5rcaN6nMm74=; b=O0qKoJFbCQHlE+jEGkzuweQIFACfqUkJnE/Kv6U0Th3mvK0fTus4FqsGJyeMMhyRbSRWFF K5WMU87Mm7XnUcxpPsAsR331XDPC4ailQQ6ESSNbaen77OBKi5q+R9Yav8KX4vG+w4+d/j eagnXIKb8FRw7XbdPho9vSGTol9/eAQ= 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-154-MecNFB9ROaaure0ci4G0eg-1; Wed, 10 Jun 2020 08:02:53 -0400 X-MC-Unique: MecNFB9ROaaure0ci4G0eg-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 F3826100A8EE; Wed, 10 Jun 2020 12:02:51 +0000 (UTC) Received: from file01.intranet.prod.int.rdu2.redhat.com (file01.intranet.prod.int.rdu2.redhat.com [10.11.5.7]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C28088FF86; Wed, 10 Jun 2020 12:02:24 +0000 (UTC) Received: from file01.intranet.prod.int.rdu2.redhat.com (localhost [127.0.0.1]) by file01.intranet.prod.int.rdu2.redhat.com (8.14.4/8.14.4) with ESMTP id 05AC2Ono028363; Wed, 10 Jun 2020 08:02:24 -0400 Received: from localhost (mpatocka@localhost) by file01.intranet.prod.int.rdu2.redhat.com (8.14.4/8.14.4/Submit) with ESMTP id 05AC2OLN028359; Wed, 10 Jun 2020 08:02:24 -0400 X-Authentication-Warning: file01.intranet.prod.int.rdu2.redhat.com: mpatocka owned process doing -bs Date: Wed, 10 Jun 2020 08:02:23 -0400 (EDT) From: Mikulas Patocka X-X-Sender: mpatocka@file01.intranet.prod.int.rdu2.redhat.com To: Herbert Xu cc: "David S. Miller" , linux-crypto@vger.kernel.org, Mike Snitzer , Milan Broz , dm-devel@redhat.com, linux-kernel@vger.kernel.org Subject: Re: crypto API and GFP_ATOMIC In-Reply-To: <20200610010450.GA6449@gondor.apana.org.au> Message-ID: References: <20200610010450.GA6449@gondor.apana.org.au> User-Agent: Alpine 2.02 (LRH 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Wed, 10 Jun 2020, Herbert Xu wrote: > On Tue, Jun 09, 2020 at 01:11:05PM -0400, Mikulas Patocka wrote: > > > > Do you have another idea how to solve this problem? > > I think the better approach would be to modify the drivers to not > allocate any memory. In general, any memory needed by the driver > to fulfil a request *should* be allocated within the crypto request > object. That's why we have the reqsize field to indicate how much > memory could be needed per request. > > Thanks, Yes, fixing the drivers would be the best - but you can hardly find any person who has all the crypto hardware and who is willing to rewrite all the drivers for it. Another possibility - I was thinking about setting CRYPTO_TFM_REQ_MAY_SLEEP in dm-crypt and calling the crypto function under memalloc_noio_save. But there are some drivers that do GFP_ATOMIC allocation regardless of CRYPTO_TFM_REQ_MAY_SLEEP. Mikulas