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 930FDCCA47C for ; Tue, 7 Jun 2022 20:52:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378530AbiFGUwO (ORCPT ); Tue, 7 Jun 2022 16:52:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358581AbiFGTwo (ORCPT ); Tue, 7 Jun 2022 15:52:44 -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 00FA6643B; Tue, 7 Jun 2022 11:21:14 -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 9273D60C1C; Tue, 7 Jun 2022 18:21:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9F211C385A2; Tue, 7 Jun 2022 18:21:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654626074; bh=a4qFuWEqZC0lHRCkY7Blx87Le22rwe0ztnrHoEFNJ4o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OIpDnjHhSrTrPTm5HQWbvdk5Bdhv2anTcWaEtGIN5IJ213UF+sRlnQOYEN7zWYw+J YyoNieIn/recqTvGrp5+i+mbAiL3PpgnHcTLH3JCzL9XFhgEy+B1CQJWBNTRpVopeg 5uOslRblivTHUtkUMtewuGJ+GTujj6VPjjiB8IpU= 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 5.17 211/772] KVM: PPC: Book3S HV Nested: L2 LPCR should inherit L1 LPES setting Date: Tue, 7 Jun 2022 18:56:43 +0200 Message-Id: <20220607164955.250649005@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164948.980838585@linuxfoundation.org> References: <20220607164948.980838585@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 316f61a4cb59..0da8c0df768d 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -5289,6 +5289,10 @@ 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 9d373f8963ee..58e05a9122ac 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