From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751437AbdH2I6t (ORCPT ); Tue, 29 Aug 2017 04:58:49 -0400 Received: from mail-wm0-f50.google.com ([74.125.82.50]:34825 "EHLO mail-wm0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750909AbdH2I6p (ORCPT ); Tue, 29 Aug 2017 04:58:45 -0400 Date: Tue, 29 Aug 2017 10:58:41 +0200 From: Ingo Molnar To: Mike Galbraith Cc: Kees Cook , LKML , Ingo Molnar , Josh Poimboeuf , Peter Zijlstra , Thomas Gleixner , Linus Torvalds , Elena Reshetova , Arnd Bergmann , "H. Peter Anvin" Subject: Re: tip -ENOBOOT - bisected to locking/refcounts, x86/asm: Implement fast refcount overflow protection Message-ID: <20170829085841.gwmdbncrm6txcezt@gmail.com> References: <1503996623.8323.20.camel@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1503996623.8323.20.camel@gmx.de> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Mike Galbraith wrote: > Greetings, > > Take 2 of KVM bisect as you work fingered $subject.  Take 1 was stymied > by build dependencies (aa5d1b81, df340524) which I foolishly tried to > skip, leading git bisect to end up handing me a list of commits that > might be busted.  During take 2, I added those two as required. > > Symptom is a few splats as below, with box finally hanging.  Network > comes up, but neither ssh nor console login is possible. Just to double check, does the patch below also cure the regression? If we don't find the bug it might be safer than a full revert. Thanks, Ingo arch/x86/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d04809921993..3b83ef8f1e9b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -55,7 +55,7 @@ config X86 select ARCH_HAS_KCOV if X86_64 select ARCH_HAS_MMIO_FLUSH select ARCH_HAS_PMEM_API if X86_64 - select ARCH_HAS_REFCOUNT +# select ARCH_HAS_REFCOUNT select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 select ARCH_HAS_SET_MEMORY select ARCH_HAS_SG_CHAIN