From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71B5FC46499 for ; Fri, 5 Jul 2019 20:37:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E08C216FD for ; Fri, 5 Jul 2019 20:37:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562359067; bh=R/NZzyRB8n045WyDB+KpdTaWasPlNT5Oy3/V7eWIzqc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=dhzr5f2/f6CGn8Urirv6mKhIM54XInkVIWrvk7+M3lzrBGQ+QELxiKAwkltAiaUsD OvBPVLHkP9cQ3vMbRe9fwDvEVF7jXhF7NtIyuTmgsMCcCPnKGD0LjYw8jDzIeM4ST1 3Ed3d+HyNo5g+OYyS4TSxygrOYHSg9KY1Gvu16IM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728027AbfGEUhp (ORCPT ); Fri, 5 Jul 2019 16:37:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:36812 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725813AbfGEUhp (ORCPT ); Fri, 5 Jul 2019 16:37:45 -0400 Received: from mail-wm1-f46.google.com (mail-wm1-f46.google.com [209.85.128.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1E6F821852 for ; Fri, 5 Jul 2019 20:37:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562359064; bh=R/NZzyRB8n045WyDB+KpdTaWasPlNT5Oy3/V7eWIzqc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=vgxt420OxsPZ7jUL6hr4u5hltEsus7q8RHArHiTsTO87dnjmEiTXBKka0QiwCS69P jH8Qff/o0KfZJ8eVeJhMhB5MXNHE4XGJ+i8YXJE8pIIHBPaTDfJL0LSTar4FdpNIQF 1WteLkIA/74U/B23jVgkxCGjuJh7w+e6Xid2Z/M8= Received: by mail-wm1-f46.google.com with SMTP id z23so10829928wma.4 for ; Fri, 05 Jul 2019 13:37:44 -0700 (PDT) X-Gm-Message-State: APjAAAV9r79atmvSYYsXGNbqacJO62ecF4c3GHSI02uRMk7h/gRK5IL2 JLXh2GUzFJRy0g1CViZ3Z4wClh6e4GWMILaqYJP/xA== X-Google-Smtp-Source: APXvYqx39v6GFd5J7B93Up85PZEU+4O/70IAN8E8Eu4hDnNLTFCQ0okxdbCQ3exNN7CQ1j4Oo3ucbBGdx4/8pUZ9Lm4= X-Received: by 2002:a1c:a942:: with SMTP id s63mr4590144wme.76.1562359062690; Fri, 05 Jul 2019 13:37:42 -0700 (PDT) MIME-Version: 1.0 References: <20190704155145.617706117@linutronix.de> <20190704155608.636478018@linutronix.de> <958a67c2-4dc0-52e6-43b2-1ebd25a59232@citrix.com> In-Reply-To: From: Andy Lutomirski Date: Fri, 5 Jul 2019 13:37:31 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [patch V2 04/25] x86/apic: Make apic_pending_intr_clear() more robust To: Thomas Gleixner Cc: Andrew Cooper , LKML , X86 ML , Nadav Amit , Ricardo Neri , Stephane Eranian , Feng Tang , Andy Lutomirski , Paolo Bonzini Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 5, 2019 at 1:25 PM Thomas Gleixner wrote: > > Andrew, > > > > > These can be addressed by setting TPR to 0x10, which will inhibit > > Right, that's easy and obvious. > This boots: diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 177aa8ef2afa..5257c40bde6c 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -1531,11 +1531,14 @@ static void setup_local_APIC(void) #endif /* - * Set Task Priority to 'accept all'. We never change this - * later on. + * Set Task Priority to 'accept all except vectors 0-31'. An APIC + * vector in the 16-31 range can be delivered otherwise, but we'll + * think it's an exception and terrible things will happen. + * We never change this later on. */ value = apic_read(APIC_TASKPRI); value &= ~APIC_TPRI_MASK; + value |= 0x10; apic_write(APIC_TASKPRI, value); apic_pending_intr_clear();