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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 6C484C43441 for ; Mon, 19 Nov 2018 16:49:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 362972147A for ; Mon, 19 Nov 2018 16:49:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="QG/9d6Kf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 362972147A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389800AbeKTDNt (ORCPT ); Mon, 19 Nov 2018 22:13:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:50752 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389790AbeKTDNs (ORCPT ); Mon, 19 Nov 2018 22:13:48 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 18A9E20C01; Mon, 19 Nov 2018 16:49:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542646175; bh=uKY2+/86QuSCqzV+4FXgUeDBMoeO3JoU3rm6NyYgFMc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QG/9d6Kft5JcoB84Zgxg7Ru+Qb7V/LS0EMMJjXXtJqVD6thpdb8TeTU0DBhzuEI4n k6p5gC+WTI8RtBuBzHZ/7rG9Lzpz8bzcJ4ipMVDT0fLiNRNfWPLqq0gv5UJYcWPZ49 zI2SV9I5B1JpjTCEUG61DJHxgj9zNPyMdIPJcIbE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Kelley , Thomas Gleixner , "devel@linuxdriverproject.org" , "daniel.lezcano@linaro.org" , "virtualization@lists.linux-foundation.org" , "jgross@suse.com" , "akataria@vmware.com" , "olaf@aepfle.de" , "apw@canonical.com" , vkuznets , "jasowang@redhat.com" , "marcelo.cerri@canonical.com" , KY Srinivasan Subject: [PATCH 4.14 064/124] x86/hyper-v: Enable PIT shutdown quirk Date: Mon, 19 Nov 2018 17:28:38 +0100 Message-Id: <20181119162625.804467418@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181119162612.951907286@linuxfoundation.org> References: <20181119162612.951907286@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Kelley commit 1de72c706488b7be664a601cf3843bd01e327e58 upstream. Hyper-V emulation of the PIT has a quirk such that the normal PIT shutdown path doesn't work, because clearing the counter register restarts the timer. Disable the counter clearing on PIT shutdown. Signed-off-by: Michael Kelley Signed-off-by: Thomas Gleixner Cc: "gregkh@linuxfoundation.org" Cc: "devel@linuxdriverproject.org" Cc: "daniel.lezcano@linaro.org" Cc: "virtualization@lists.linux-foundation.org" Cc: "jgross@suse.com" Cc: "akataria@vmware.com" Cc: "olaf@aepfle.de" Cc: "apw@canonical.com" Cc: vkuznets Cc: "jasowang@redhat.com" Cc: "marcelo.cerri@canonical.com" Cc: KY Srinivasan Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1541303219-11142-3-git-send-email-mikelley@microsoft.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/mshyperv.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -243,6 +244,16 @@ static void __init ms_hyperv_init_platfo if (efi_enabled(EFI_BOOT)) x86_platform.get_nmi_reason = hv_get_nmi_reason; + /* + * Hyper-V VMs have a PIT emulation quirk such that zeroing the + * counter register during PIT shutdown restarts the PIT. So it + * continues to interrupt @18.2 HZ. Setting i8253_clear_counter + * to false tells pit_shutdown() not to zero the counter so that + * the PIT really is shutdown. Generation 2 VMs don't have a PIT, + * and setting this value has no effect. + */ + i8253_clear_counter_on_shutdown = false; + #if IS_ENABLED(CONFIG_HYPERV) /* * Setup the hook to get control post apic initialization.