From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751313AbdKVGgl (ORCPT ); Wed, 22 Nov 2017 01:36:41 -0500 Received: from mail-wr0-f179.google.com ([209.85.128.179]:33994 "EHLO mail-wr0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751079AbdKVGgj (ORCPT ); Wed, 22 Nov 2017 01:36:39 -0500 X-Google-Smtp-Source: AGs4zMaT0OtxpvAqgwElCqWlzJsW/35GSo3v9Wlpiyw7Q/TU/aka+QCDdg3zhZH3fIQoJLpDoowuew== Date: Wed, 22 Nov 2017 07:36:36 +0100 From: Ingo Molnar To: Andy Lutomirski Cc: X86 ML , Borislav Petkov , "linux-kernel@vger.kernel.org" , Brian Gerst , Dave Hansen , Linus Torvalds , Josh Poimboeuf Subject: Re: [PATCH v2 00/18] Entry stack switching Message-ID: <20171122063636.wib53q255n4spa5s@gmail.com> References: <20171122062257.ivp5fbcy2k4mlfdm@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171122062257.ivp5fbcy2k4mlfdm@gmail.com> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Ingo Molnar wrote: > > * Andy Lutomirski wrote: > > > This sets up stack switching, including for SYSCALL. I think it's > > in decent shape. > > > > Known issues: > > - I think we're going to want a way to turn the stack switching on and > > off either at boot time or at runtime. It should be fairly straightforward > > to make it work. > > > > - I think the ORC unwinder isn't so good at dealing with stack overflows. > > It bails too early (I think), resulting in lots of ? entries. This > > isn't a regression with this series -- it's just something that could > > be improved. > > > > Ingo, patch 1 may be tip/urgent material. It fixes what I think is > > a bug in Xen. I'm having a hard time testing because it's being > > masked by a bigger unrelated bug that's keeping Xen from booting > > when configured to hit the bug I'm fixing. (The latter bug goes at > > least back to v4.13, I think I know roughtly what's wrong, and I've > > reported it to the maintainers.) > > Hm, with this series the previous IRQ vector bug appears again: > > [ 51.156370] do_IRQ: 16.34 No irq handler for vector > [ 57.511030] do_IRQ: 16.34 No irq handler for vector > [ 57.528335] do_IRQ: 16.34 No irq handler for vector > [ 57.533256] do_IRQ: 16.34 No irq handler for vector > [ 63.991913] do_IRQ: 16.34 No irq handler for vector > [ 63.996810] do_IRQ: 16.34 No irq handler for vector > > I've attached the reproducer config. Note that the system appears to be working to > a certain extent (I could ssh to it and extract its config), but produces these > warnings sporadically. > > Also note that this is the same AMD system tha had irq-tracing/lockdep troubles > yesterday. So maybe this warning is related and we either have broken lockdep, or > these IRQ vector warnings. Yeah, so I just double checked, if from the latest series I revert: x86/entry/64: Fix entry_SYSCALL_64_after_hwframe() IRQ tracing then I (no surprise) get the bootup lockdep warning - but don't get the IRQ vector warnings. Thanks, Ingo