From patchwork Tue Aug 14 20:14:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Salisbury X-Patchwork-Id: 957719 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 41qkMf0RVZz9sBx; Wed, 15 Aug 2018 06:14:22 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1fpfhl-00021W-5l; Tue, 14 Aug 2018 20:14:13 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1fpfhi-00020z-Lb for kernel-team@lists.ubuntu.com; Tue, 14 Aug 2018 20:14:10 +0000 Received: from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1fpfhi-0003qm-BC for kernel-team@lists.ubuntu.com; Tue, 14 Aug 2018 20:14:10 +0000 Received: by salisbury (Postfix, from userid 1000) id 4FB3F7E0858; Tue, 14 Aug 2018 16:14:09 -0400 (EDT) From: Joseph Salisbury To: kernel-team@lists.ubuntu.com Subject: [SRU][Bionic][PATCH 0/1] x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths Date: Tue, 14 Aug 2018 16:14:08 -0400 Message-Id: X-Mailer: git-send-email 2.17.1 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" BugLink: https://bugs.launchpad.net/bugs/1777338 == SRU Justification == Mainline commit 1f50ddb4f418 introduced a regression. That commit added speculative_store_bypass_ht_init() to the per-CPU initialization sequence. However, speculative_store_bypass_ht_init() needs to be called on each CPU for PV guests, as well. The regresssion prevents systems from booting. The patch to fix this regression has also been cc'd to upstream stable, but it has not landed in Bionic as of yet. == Fix == 74899d92e666 ("x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths") == Regression Potential == Low. This patch fixes a current regressionThis patch has also been submitted to upstream stable, so it has had additional upstream review. == Test Case == A test kernel was built with this patch and tested by the original bug reporter. The bug reporter states the test kernel resolved the bug. Juergen Gross (1): x86/xen: Add call of speculative_store_bypass_ht_init() to PV paths arch/x86/xen/smp_pv.c | 5 +++++ 1 file changed, 5 insertions(+) Acked-by: Khalid Elmously