Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754841AbWL1M6p (ORCPT ); Thu, 28 Dec 2006 07:58:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754842AbWL1M6p (ORCPT ); Thu, 28 Dec 2006 07:58:45 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:59661 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754841AbWL1M6o (ORCPT ); Thu, 28 Dec 2006 07:58:44 -0500 Date: Thu, 28 Dec 2006 13:55:44 +0100 From: Ingo Molnar To: Avi Kivity Cc: kvm-devel , linux-kernel , Andrew Morton , Linus Torvalds Subject: Re: [patch] kvm: fix GFP_KERNEL allocation in atomic section in kvm_dev_ioctl_create_vcpu() Message-ID: <20061228125544.GA31207@elte.hu> References: <45939755.7010603@qumranet.com> <20061228124224.GA28573@elte.hu> <4593BEE6.30206@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4593BEE6.30206@qumranet.com> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -5.9 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-5.9 required=5.9 tests=ALL_TRUSTED,BAYES_00 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 925 Lines: 23 * Avi Kivity wrote: > >fix a GFP_KERNEL allocation in atomic section bug: > >kvm_dev_ioctl_create_vcpu() called kvm_mmu_init(), which calls > >alloc_pages(), while holding the vcpu. The fix is to set up the MMU > >state earlier, it does not require a loaded CPU state. > > Yes it does. It calls nonpaging_init_context() which calls > vmx_set_cr3() which promptly trashes address space of the VM that > previously ran on that vcpu (or, if there were none, logs a vmwrite > error). ok, i missed that. Nevertheless the problem of the nonatomic alloc remains. I guess a kvm_mmu_init() needs to be split into kvm_mmu_create() and kvm_mmu_setup()? Ingo - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/