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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 628B0CCA48D for ; Tue, 7 Jun 2022 18:31:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352688AbiFGSbM (ORCPT ); Tue, 7 Jun 2022 14:31:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352060AbiFGSCh (ORCPT ); Tue, 7 Jun 2022 14:02:37 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9B756B655; Tue, 7 Jun 2022 10:46:54 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 71C53616B6; Tue, 7 Jun 2022 17:46:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D8B1C34115; Tue, 7 Jun 2022 17:46:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654624012; bh=Z8axk3wY4vH8/Dseo94rtU2nY3WpgHiZ0Yz2/nELLWk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oeUTkZn6+U3Y3Ifr5RPPALo4EyuxZ8MSwpoIgZ49FRW7+/ONWjrN2AIMwYcLsIROY Su6d1p0y2u5DYJS7arfu7HuGHHI/xAq1QcMrVEfGx3QGagS1MEAW91bZrJO3wH51WW U8GVMFeA55oN7apIOLkSK1UZpeTDh9+itusb6G6w= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Piggin , Fabiano Rosas , Michael Ellerman , Sasha Levin Subject: [PATCH 5.15 171/667] KVM: PPC: Book3S HV Nested: L2 LPCR should inherit L1 LPES setting Date: Tue, 7 Jun 2022 18:57:16 +0200 Message-Id: <20220607164939.941318184@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164934.766888869@linuxfoundation.org> References: <20220607164934.766888869@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nicholas Piggin [ Upstream commit 2852ebfa10afdcefff35ec72c8da97141df9845c ] The L1 should not be able to adjust LPES mode for the L2. Setting LPES if the L0 needs it clear would cause external interrupts to be sent to L2 and missed by the L0. Clearing LPES when it may be set, as typically happens with XIVE enabled could cause a performance issue despite having no native XIVE support in the guest, because it will cause mediated interrupts for the L2 to be taken in HV mode, which then have to be injected. Signed-off-by: Nicholas Piggin Reviewed-by: Fabiano Rosas Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220303053315.1056880-7-npiggin@gmail.com Signed-off-by: Sasha Levin --- arch/powerpc/kvm/book3s_hv.c | 4 ++++ arch/powerpc/kvm/book3s_hv_nested.c | 3 +-- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 7fa685711669..eba77096c443 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -5235,6 +5235,10 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm) kvm->arch.host_lpcr = lpcr = mfspr(SPRN_LPCR); lpcr &= LPCR_PECE | LPCR_LPES; } else { + /* + * The L2 LPES mode will be set by the L0 according to whether + * or not it needs to take external interrupts in HV mode. + */ lpcr = 0; } lpcr |= (4UL << LPCR_DPFD_SH) | LPCR_HDICE | diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index 6c4e0e93105f..ddea14e5cb5e 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -261,8 +261,7 @@ static void load_l2_hv_regs(struct kvm_vcpu *vcpu, /* * Don't let L1 change LPCR bits for the L2 except these: */ - mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD | - LPCR_LPES | LPCR_MER; + mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD | LPCR_MER; /* * Additional filtering is required depending on hardware -- 2.35.1