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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 9B305C33CB2 for ; Wed, 29 Jan 2020 05:46:39 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 50D8E2071E for ; Wed, 29 Jan 2020 05:46:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 50D8E2071E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 486stP0F9vzDqFG for ; Wed, 29 Jan 2020 16:46:37 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 486sDl4hf2zDqMm for ; Wed, 29 Jan 2020 16:17:27 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix, from userid 1034) id 486sDl09qNz9sRh; Wed, 29 Jan 2020 16:17:26 +1100 (AEDT) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: 736bcdd3a9fc672af33fb83230ecd0570ec38ec6 In-Reply-To: <20191206031722.25781-1-jniethe5@gmail.com> To: Jordan Niethe , linuxppc-dev@lists.ozlabs.org, kvm-ppc@vger.kernel.org From: Michael Ellerman Subject: Re: [PATCH v3] powerpc/mm: Remove kvm radix prefetch workaround for Power9 DD2.2 Message-Id: <486sDl09qNz9sRh@ozlabs.org> Date: Wed, 29 Jan 2020 16:17:26 +1100 (AEDT) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jordan Niethe , oohall@gmail.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, 2019-12-06 at 03:17:22 UTC, Jordan Niethe wrote: > Commit a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with > KVM") introduced a number of workarounds as coming out of a guest with > the mmu enabled would make the cpu would start running in hypervisor > state with the PID value from the guest. The cpu will then start > prefetching for the hypervisor with that PID value. > > In Power9 DD2.2 the cpu behaviour was modified to fix this. When > accessing Quadrant 0 in hypervisor mode with LPID != 0 prefetching will > not be performed. This means that we can get rid of the workarounds for > Power9 DD2.2 and later revisions. Add a new cpu feature > CPU_FTR_P9_RADIX_PREFETCH_BUG to indicate if the workarounds are needed. > > Signed-off-by: Jordan Niethe Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/736bcdd3a9fc672af33fb83230ecd0570ec38ec6 cheers