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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 3593FC3A5A1 for ; Wed, 28 Aug 2019 11:13:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F0C4422CF5 for ; Wed, 28 Aug 2019 11:13:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566990808; bh=J6wpvtEGCR/gD5nst0XMLcp4+fk8rqX6ybJoQkdxQWQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Q33a8iV3F7xB+fERi30IjytAWxXKil4MWkD73BMkxLTroKsYsWKfxEZhWCCjVVjOR 1+cr28Wd7pXVe8k6pTdR9HOCVD8RBsSrCIqfCHnCDMDFfJlphofkxbhK/kKrms4Jjv Bff3KErz4iPAZImeL/l7oEQ0nwLBR/M5XZjW6bBU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726550AbfH1LN0 (ORCPT ); Wed, 28 Aug 2019 07:13:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:35654 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726253AbfH1LN0 (ORCPT ); Wed, 28 Aug 2019 07:13:26 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 D6B112189D; Wed, 28 Aug 2019 11:13:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566990805; bh=J6wpvtEGCR/gD5nst0XMLcp4+fk8rqX6ybJoQkdxQWQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=f/qx0YWPpnGPmOmiuyOHizlQBzTKHmYlNofQqIpexfo3XFZimBt29M6vXcnyJrDCV 9+Sg3e4d+WlWB14eFix0eDhfu0vu0Bn4p5epE3uWmCw1uYBw48C/EW7lxP13hsxt62 LxZ/Vc4AocGshcvvSQx/f2w1y4fMeAW45BtdJ2PQ= Date: Wed, 28 Aug 2019 07:13:23 -0400 From: Sasha Levin To: Greg KH Cc: Yu Chen , linux-kernel@vger.kernel.org, stable-commits@vger.kernel.org Subject: Re: Patch "x86/pm: Introduce quirk framework to save/restore extra MSR registers around suspend/resume" has been added to the 4.4-stable tree Message-ID: <20190828111323.GA5281@sasha-vm> References: <20190828041240.12F5221883@mail.kernel.org> <20190828084351.GC29927@kroah.com> <20190828090043.GA7589@chenyu-office.sh.intel.com> <20190828091155.GA32011@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190828091155.GA32011@kroah.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 28, 2019 at 11:11:55AM +0200, Greg KH wrote: >On Wed, Aug 28, 2019 at 05:00:44PM +0800, Yu Chen wrote: >> On Wed, Aug 28, 2019 at 10:43:51AM +0200, Greg KH wrote: >> > On Wed, Aug 28, 2019 at 12:12:39AM -0400, Sasha Levin wrote: >> > > This is a note to let you know that I've just added the patch titled >> > > >> > > x86/pm: Introduce quirk framework to save/restore extra MSR registers around suspend/resume >> > > >> > > to the 4.4-stable tree which can be found at: >> > > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary >> > > >> > > The filename of the patch is: >> > > x86-pm-introduce-quirk-framework-to-save-restore-ext.patch >> > > and it can be found in the queue-4.4 subdirectory. >> > > >> > > If you, or anyone else, feels it should not be added to the stable tree, >> > > please let know about it. >> > > >> > > >> > > >> > > commit d63273440aa0fdebc30d0c931f15f79beb213134 >> > > Author: Chen Yu >> > > Date: Wed Nov 25 01:03:41 2015 +0800 >> > > >> > > x86/pm: Introduce quirk framework to save/restore extra MSR registers around suspend/resume >> > > >> > > A bug was reported that on certain Broadwell platforms, after >> > > resuming from S3, the CPU is running at an anomalously low >> > > speed. >> > > >> > > It turns out that the BIOS has modified the value of the >> > > THERM_CONTROL register during S3, and changed it from 0 to 0x10, >> > > thus enabled clock modulation(bit4), but with undefined CPU Duty >> > > Cycle(bit1:3) - which causes the problem. >> > > >> > > Here is a simple scenario to reproduce the issue: >> > > >> > > 1. Boot up the system >> > > 2. Get MSR 0x19a, it should be 0 >> > > 3. Put the system into sleep, then wake it up >> > > 4. Get MSR 0x19a, it shows 0x10, while it should be 0 >> > > >> > > Although some BIOSen want to change the CPU Duty Cycle during >> > > S3, in our case we don't want the BIOS to do any modification. >> > > >> > > Fix this issue by introducing a more generic x86 framework to >> > > save/restore specified MSR registers(THERM_CONTROL in this case) >> > > for suspend/resume. This allows us to fix similar bugs in a much >> > > simpler way in the future. >> > > >> > > When the kernel wants to protect certain MSRs during suspending, >> > > we simply add a quirk entry in msr_save_dmi_table, and customize >> > > the MSR registers inside the quirk callback, for example: >> > > >> > > u32 msr_id_need_to_save[] = {MSR_ID0, MSR_ID1, MSR_ID2...}; >> > > >> > > and the quirk mechanism ensures that, once resumed from suspend, >> > > the MSRs indicated by these IDs will be restored to their >> > > original, pre-suspend values. >> > > >> > > Since both 64-bit and 32-bit kernels are affected, this patch >> > > covers the common 64/32-bit suspend/resume code path. And >> > > because the MSRs specified by the user might not be available or >> > > readable in any situation, we use rdmsrl_safe() to safely save >> > > these MSRs. >> > > >> > > Reported-and-tested-by: Marcin Kaszewski >> > > Signed-off-by: Chen Yu >> > > Acked-by: Rafael J. Wysocki >> > > Acked-by: Pavel Machek >> > > Cc: Andy Lutomirski >> > > Cc: Borislav Petkov >> > > Cc: Brian Gerst >> > > Cc: Denys Vlasenko >> > > Cc: H. Peter Anvin >> > > Cc: Linus Torvalds >> > > Cc: Peter Zijlstra >> > > Cc: Thomas Gleixner >> > > Cc: bp@suse.de >> > > Cc: len.brown@intel.com >> > > Cc: linux@horizon.com >> > > Cc: luto@kernel.org >> > > Cc: rjw@rjwysocki.net >> > > Link: http://lkml.kernel.org/r/c9abdcbc173dd2f57e8990e304376f19287e92ba.1448382971.git.yu.c.chen@intel.com >> > > [ More edits to the naming of data structures. ] >> > > Signed-off-by: Ingo Molnar >> > >> > No git id of the patch in Linus's tree, or your signed-off-by? >> > >> I think the commit id in Linus'tree should be 7a9c2dd08eadd5c6943115dbbec040c38d2e0822 > >Ah, and Sasha added it because a later patch needed it :( > >Sasha, can you fix this patch's headers up to be in the "proper" format? Yes, I brought it in as a dependency but cherry picked instead of using my scripts by mistake. I'll fix up the patch in the queue. -- Thanks, Sasha