Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753350Ab0GMDdy (ORCPT ); Mon, 12 Jul 2010 23:33:54 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:33793 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753079Ab0GMDdw (ORCPT ); Mon, 12 Jul 2010 23:33:52 -0400 Message-ID: <4C3BDDA3.2060900@kernel.org> Date: Mon, 12 Jul 2010 20:29:39 -0700 From: Yinghai Lu User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10) Gecko/20100520 SUSE/3.0.5 Thunderbird/3.0.5 MIME-Version: 1.0 To: Ingo Molnar , "H. Peter Anvin" , Thomas Gleixner , Suresh Siddha CC: "linux-kernel@vger.kernel.org" Subject: Re: tip/master broken with x2apic and kexec References: <4C3BD6AA.3070908@kernel.org> In-Reply-To: <4C3BD6AA.3070908@kernel.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: acsmt354.oracle.com [141.146.40.154] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090204.4C3BDE99.0028,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1616 Lines: 38 On 07/12/2010 07:59 PM, Yinghai Lu wrote: > tip/master: > system1: BIOS enabled x2apic, first kernel boot well, and when kexec second kernel will cause system instant reboot. > > system2: BIOS not enable x2apic, first kernel boot well and enable x2apic, and kexec second kernel well. but when kexec third kernel will case system instant reboot. > > linus' tree is ok. > > but for system2 if boot with nox2apic ,intr-remaping off, iommu off, the kexec loop test will pass. > > the problem looks start in recent two or three weeks. > offending patch is commit 83a7a2ad2a9173dcabc05df0f01d1d85b7ba1c2c Author: H. Peter Anvin Date: Thu Jun 10 00:10:43 2010 +0000 x86, alternatives: Use 16-bit numbers for cpufeature index We already have cpufeature indicies above 255, so use a 16-bit number for the alternatives index. This consumes a padding field and so doesn't add any size, but it means that abusing the padding field to create assembly errors on overflow no longer works. We can retain the test simply by redirecting it to the .discard section, however. [ v3: updated to include open-coded locations ] Signed-off-by: H. Peter Anvin LKML-Reference: Signed-off-by: H. Peter Anvin -- 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/