From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762256AbYEOUc3 (ORCPT ); Thu, 15 May 2008 16:32:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752202AbYEOUcV (ORCPT ); Thu, 15 May 2008 16:32:21 -0400 Received: from mtagate6.de.ibm.com ([195.212.29.155]:31883 "EHLO mtagate6.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752086AbYEOUcU (ORCPT ); Thu, 15 May 2008 16:32:20 -0400 From: Christian Borntraeger To: Jeff Garzik Subject: Re: Virt RNG? Date: Thu, 15 May 2008 22:31:56 +0200 User-Agent: KMail/1.9.9 Cc: LKML , virtualization@lists.osdl.org, Rusty Russell , jeremy@xensource.com, Herbert Xu , Avi Kivity References: <482C8595.5030509@garzik.org> In-Reply-To: <482C8595.5030509@garzik.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200805152231.56967.borntraeger@de.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Donnerstag, 15. Mai 2008 schrieb Jeff Garzik: > Has anyone yet written a "hw" RNG module for virt, that reads the host's > random number pool? > > All this talk[1] about IRQF_SAMPLE_RANDOM in network drivers reminds me > that virt guest instances should be grabbing random numbers from the > host, especially if the host has a hardware RNG. Yes, there was a drivers/char/hw_random/virtio-rng.c in Rusty's lguest repository. http://www.mail-archive.com/virtualization%40lists.linux-foundation.org/msg02902.html I have tested this driver with this fix https://lists.linux-foundation.org/pipermail/virtualization/2008-January/009737.html and it worked. As it transfers only 4 byte per hypercall it is not mindblowingly fast, but I guess it is fast enough. Dont know why it never hit mainline. Christian