From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from 10.mo179.mail-out.ovh.net (10.mo179.mail-out.ovh.net [46.105.79.46]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3y5VBh3QTxzDqhf for ; Tue, 3 Oct 2017 04:53:15 +1100 (AEDT) Received: from player168.ha.ovh.net (b6.ovh.net [213.186.33.56]) by mo179.mail-out.ovh.net (Postfix) with ESMTP id 7CF6D6CFBD for ; Mon, 2 Oct 2017 19:53:12 +0200 (CEST) Subject: Re: [PATCH 0/2] powerpc/xive: fix CPU hot unplug To: Benjamin Herrenschmidt , linuxppc-dev@lists.ozlabs.org Cc: Michael Ellerman , David Gibson References: <20170923082656.27219-1-clg@kaod.org> <378a1945-6263-dca7-3912-b4a2c61794b8@kaod.org> <1506963157.25065.48.camel@kernel.crashing.org> From: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= Message-ID: <1975733a-4c69-a35b-525e-eed1f0d4458c@kaod.org> Date: Mon, 2 Oct 2017 19:53:06 +0200 MIME-Version: 1.0 In-Reply-To: <1506963157.25065.48.camel@kernel.crashing.org> Content-Type: text/plain; charset=utf-8 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 10/02/2017 06:52 PM, Benjamin Herrenschmidt wrote: > On Mon, 2017-10-02 at 18:27 +0200, Cédric Le Goater wrote: >> On 09/23/2017 10:26 AM, Cédric Le Goater wrote: >>> Hi, >>> >>> Here are a couple of small fixes to support CPU hot unplug. There are >>> still some issues to be investigated as, in some occasions, after a >>> couple of plug and unplug, the cpu which was removed receives a 'lost' >>> interrupt. This showed to be the decrementer under QEMU. >> >> So this seems to be a QEMU issue only which can be solved by >> removing the DEE bit from the LPCR on P9 processor when the CPU >> is stopped in rtas. PECE3 bit on P8 processors. > > It should be the same bit no ? yes and it is for the QEMU side of the world. C. >> I think these patches are valuable fixes for 4.14. The first >> is trivial and the second touches the common xive part but it >> is only called on the pseries platform. >> >> Could you please take a look ? >> >> Thanks, >> >> C. >> >>> Nevertheless, these patches are required and provide a significant >>> improvement to support CPU removal. >>> >>> Tested under a phyp and a XIVE QEMU model for pseries. >>> >>> Thanks, >>> >>> C. >>> >>> Cédric Le Goater (2): >>> powerpc/xive: fix IPI reset >>> powerpc/xive: fix cpu removal >>> >>> arch/powerpc/sysdev/xive/common.c | 8 ++++++++ >>> arch/powerpc/sysdev/xive/spapr.c | 4 ++++ >>> 2 files changed, 12 insertions(+) >>>