Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758198AbZFIRUp (ORCPT ); Tue, 9 Jun 2009 13:20:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755791AbZFIRUh (ORCPT ); Tue, 9 Jun 2009 13:20:37 -0400 Received: from qw-out-2122.google.com ([74.125.92.25]:57673 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757373AbZFIRUf (ORCPT ); Tue, 9 Jun 2009 13:20:35 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=euC/J31ZMCMWXQHrXh68pFmOE5genvrSfBrdSpzLhzi2jNVMb6R3eJZAq6ABi7Cz0m ZpdDi1RwXWzpRHysUPBOM2/YgY5ItlDF5BlHzp8F3uXVYZGnEUta4WQD5/cz8v6s6Yj+ tTz9vC4QmAfKACt49GC/nH+Ur6myBE4uxZmM8= MIME-Version: 1.0 In-Reply-To: <20090608170437.1c2386a5@nehalam> References: <20090608091544.53a94235@nehalam> <20090608170437.1c2386a5@nehalam> Date: Tue, 9 Jun 2009 10:20:36 -0700 X-Google-Sender-Auth: ab374d2c059ac31e Message-ID: Subject: Re: [Bug #13116] Can't boot with nosmp From: Dan Williams To: Stephen Hemminger Cc: Rusty Russell , "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , avi@redhat.com Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1699 Lines: 45 On Mon, Jun 8, 2009 at 5:04 PM, Stephen Hemminger wrote: > I did some more debugging, and the problem appears to be that > booting with nosmp still leaves all the CPU's present in the cpu > possible mask. So code like dma engine (or loopback device), that > use alloc_percpu get broken. > > Not sure why all the cpu's are still showing up in the possible mask. > Rusty? do you have an answer. Would this recent commit also fix this issue? commit a4c0364be3f43d3e17fe19270f8b3d64881606e6 Author: Avi Kivity Date: Sat Jun 6 12:34:39 2009 +0300 KVM: Explicity initialize cpus_hardware_enabled Under CONFIG_MAXSMP, cpus_hardware_enabled is allocated from the heap and not statically initialized. This causes a crash on reboot when kvm thinks vmx is enabled on random nonexistent cpus and accesses nonexistent percpu lists. Fix by explicitly clearing the variable. Cc: stable@kernel.org Reported-and-tested-by: Yinghai Lu Signed-off-by: Avi Kivity diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1ecbe23..4293528 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2305,6 +2305,7 @@ int kvm_init(void *opaque, unsigned int vcpu_size, r = -ENOMEM; goto out_free_0; } + cpumask_clear(cpus_hardware_enabled); r = kvm_arch_hardware_setup(); if (r < 0) -- 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/