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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B97FC433EF for ; Mon, 11 Oct 2021 14:17:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 07F4560EE2 for ; Mon, 11 Oct 2021 14:17:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244484AbhJKOTt (ORCPT ); Mon, 11 Oct 2021 10:19:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:38724 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243284AbhJKORZ (ORCPT ); Mon, 11 Oct 2021 10:17:25 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BB29F610F8; Mon, 11 Oct 2021 14:10:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1633961420; bh=CYi226aFCmG3dK7IyYGdL3Cab4XEkOb9x+YX6Rga9/0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=y48JT8pKxOhg9qC6K46v/5e+pZHnf+YqdscSHFBQiK+OWzDtOtAcWscDGdb6UpxHa YJA8p3lyADvIniXmzhq42AQXani2eWnpEy2OLHD8tX4BdNVlJLOoa5WXp6/0Hv95Eo sEw+/iJeX4k3rMQ4/hjG17Y2jZ9omnaPrM3W/hs4= Date: Mon, 11 Oct 2021 16:05:50 +0200 From: Greg Kroah-Hartman To: Jakub Kicinski Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Thomas Gleixner , "Rafael J. Wysocki" , Kai-Heng Feng , Bjorn Helgaas Subject: Re: [PATCH 5.4 51/52] x86/hpet: Use another crystalball to evaluate HPET usability Message-ID: References: <20211011134503.715740503@linuxfoundation.org> <20211011134505.483011431@linuxfoundation.org> <20211011065931.78965dff@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211011065931.78965dff@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Oct 11, 2021 at 06:59:31AM -0700, Jakub Kicinski wrote: > On Mon, 11 Oct 2021 15:46:20 +0200 Greg Kroah-Hartman wrote: > > From: Thomas Gleixner > > > > commit 6e3cd95234dc1eda488f4f487c281bac8fef4d9b upstream. > > > > On recent Intel systems the HPET stops working when the system reaches PC10 > > idle state. > > > > The approach of adding PCI ids to the early quirks to disable HPET on > > these systems is a whack a mole game which makes no sense. > > > > Check for PC10 instead and force disable HPET if supported. The check is > > overbroad as it does not take ACPI, intel_idle enablement and command > > line parameters into account. That's fine as long as there is at least > > PMTIMER available to calibrate the TSC frequency. The decision can be > > overruled by adding "hpet=force" on the kernel command line. > > > > Remove the related early PCI quirks for affected Ice Cake and Coffin Lake > > systems as they are not longer required. That should also cover all > > other systems, i.e. Tiger Rag and newer generations, which are most > > likely affected by this as well. > > > > Fixes: Yet another hardware trainwreck > > Reported-by: Jakub Kicinski > > Signed-off-by: Thomas Gleixner > > Tested-by: Jakub Kicinski > > Reviewed-by: Rafael J. Wysocki > > Cc: stable@vger.kernel.org > > Cc: Kai-Heng Feng > > Cc: Bjorn Helgaas > > Signed-off-by: Greg Kroah-Hartman > > FWIW I've never seen any problems prior to Paul's rework of bad clock > detection in 5.13. Backports to 5.4 and 5.10 are not necessary. Given that the hardware is still just as broken in those older kernels, why not? thanks, greg k-h