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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,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 CAF92C433DF for ; Mon, 15 Jun 2020 07:53:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A105B2067B for ; Mon, 15 Jun 2020 07:53:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="AlyICsaS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728988AbgFOHx6 (ORCPT ); Mon, 15 Jun 2020 03:53:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728426AbgFOHx5 (ORCPT ); Mon, 15 Jun 2020 03:53:57 -0400 Received: from merlin.infradead.org (unknown [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BEB9AC061A0E for ; Mon, 15 Jun 2020 00:53:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=NFpMfrG9hSicO32ZjKxBqJx63rGzA3U+MKaGGKR/+vs=; b=AlyICsaSytn6UKQYHxgxKALtpV davZqqhBuoT/RALUO6rpXUvSYemJAE7crjXLyGQz3wbtvJTFfNaoi1Rglp6dVg2CZH9x4sLqemnu+ JklbibNrlyLTx/g+gc6cJqZ8uENDkmFIgntMBecpf7QJUgDOcc4+Tj7zectWHzIWlHd3EuG7t814g +HYj3pC5QDAkoOzs/dcpjIJjYIHYvoTsSP0JEPJ1TUnTQ4+WpbTcVnJyVT/SF1TFsWwxusgVOJ9RB tHGz1xreZFmg2kBRIxtz3nKYW7EGfKHYpY+Xt6vG7x6b7wJGzxfsH3whAUU2bWyLmRByvFylgrVdv DZNY7+/g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jkjvi-0005ii-KF; Mon, 15 Jun 2020 07:53:18 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 28ED530604B; Mon, 15 Jun 2020 09:53:13 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 107F021059BE3; Mon, 15 Jun 2020 09:53:13 +0200 (CEST) Date: Mon, 15 Jun 2020 09:53:13 +0200 From: Peter Zijlstra To: Fenghua Yu Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , H Peter Anvin , David Woodhouse , Lu Baolu , Frederic Barrat , Andrew Donnellan , Felix Kuehling , Joerg Roedel , Dave Hansen , Tony Luck , Ashok Raj , Jacob Jun Pan , Dave Jiang , Yu-cheng Yu , Sohil Mehta , Ravi V Shankar , linux-kernel , x86 , iommu@lists.linux-foundation.org, amd-gfx , linuxppc-dev Subject: Re: [PATCH v2 12/12] x86/traps: Fix up invalid PASID Message-ID: <20200615075313.GJ2497@hirez.programming.kicks-ass.net> References: <1592008893-9388-1-git-send-email-fenghua.yu@intel.com> <1592008893-9388-13-git-send-email-fenghua.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1592008893-9388-13-git-send-email-fenghua.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 12, 2020 at 05:41:33PM -0700, Fenghua Yu wrote: > @@ -447,6 +458,18 @@ dotraplinkage void do_general_protection(struct pt_regs *regs, long error_code) > int ret; > > RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU"); > + > + /* > + * Perform the check for a user mode PASID exception before enable > + * interrupts. Doing this here ensures that the PASID MSR can be simply > + * accessed because the contents are known to be still associated > + * with the current process. > + */ > + if (user_mode(regs) && fixup_pasid_exception()) { > + cond_local_irq_enable(regs); > + return; OK, so we're done with the exception, lets enable interrupts? > + }