From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 55A3A606A327 for ; Wed, 11 Nov 2026 17:16:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=M/8Tvn9q; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=kFzskHgB DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=2LtHlzenH8P0Let9eUokfApdyyGworpP/r1pDQ+TQU8=; b=M/8Tvn9qDYCOgEJC+Iqr9DZykA vJdnJcE45yO+4G6NS9BiijvdzAG+zN9sORIHHWSQIzK0fDM99yb8DnlXBaRWnxww3s/Msam+/P/iI Qc9wJVrYw7Jc/sreTyRVYX6AJYY5kT+YjjDLpLeBxpxOtDDwYcBwCVmwphoyUktfe1ddggfemfqlf pjz9zOsdt5byQYN1AcSaDwL0IWSTuonAI3f9envN1dt0QKJunKPcciUCUHjowc4X8+FM6Qt/SZUdf oP5uwsPsXAt7L9SouttgM0388N1A5ATNIi3c25bnHW5SQ85dRV7E+FWDHZK+jz2ywChA9lOfrlkk7 NRk7IdfA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRBwJ-00000007Hcu-1VMA; Wed, 11 Nov 2026 17:16:51 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRBwH-00000007HcQ-3Fvy for linux-arm-kernel@lists.infradead.org; Wed, 11 Nov 2026 17:16:50 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BDCE6339; Wed, 11 Nov 2026 09:16:45 -0800 (PST) Received: from raptor (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D4B2D3F632; Wed, 11 Nov 2026 09:16:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794417408; bh=I5J2kVvdKW4OqPmoJ/nQAip3vlK/SWhiWTZU2FsT3FI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kFzskHgBfJ2MED+UEtFv80JX+XpZT8ayy4tQXWR1Bkb8jNcjKtwWklLBsjqzy2EW2 WxBRsR3lK17xRh29ko6PvPw39RRBOceP94t6lHLkMTWvzQvje1GggtxXs6JrwOlJ/U S2CHp4colJHqGlGTbLxoduOpLbJVoQXP3Q9PKwQM= Date: Wed, 11 Nov 2026 17:16:37 +0000 From: Alexandru Elisei To: "Lorenzo Stoakes (ARM)" Cc: maz@kernel.org, oupton@kernel.org, fuad.tabba@linux.dev, joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, will@kernel.org, mark.rutland@arm.com, linux-perf-users@vger.kernel.org, catalin.marinas@arm.com, james.clark@linaro.org Subject: Re: [RFC PATCH v7 03/28] KVM: arm64: Add CONFIG_KVM_ARM_SPE Kconfig option Message-ID: References: <20260903160623.315525-1-alexandru.elisei@arm.com> <20260903160623.315525-4-alexandru.elisei@arm.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261111_091649_854761_B5C3809E X-CRM114-Status: GOOD ( 25.21 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-15.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Hi, On Thu, Oct 15, 2026 at 03:15:18PM +0100, Lorenzo Stoakes (ARM) wrote: > On Thu, Sep 03, 2026 at 05:05:58PM +0100, Alexandru Elisei wrote: > > Add a new configuration option that will be used for KVM SPE emulation. > > CONFIG_KVM_ARM_SPE depends on the SPE driver being loaded because: > > > > 1. The SPE driver maintains a cpumask of physical CPUs that support SPE, > > and that will be used by KVM to emulate SPE on heterogeneous systems. > > I guess e.g. big.LITTLE? That's the marketing term for it, yes. > > > > > 2. KVM will rely on the SPE driver enabling the SPE interrupt at the GIC > > level. > > > > The option will become user selectable after SPE support in KVM is > > implemented. > > > > Signed-off-by: Alexandru Elisei > > With nit addressed the redundant dependency removed (both noted below), > LGTM and: > > Reviewed-by: Lorenzo Stoakes (ARM) > > > --- > > arch/arm64/kvm/Kconfig | 9 +++++++++ > > 1 file changed, 9 insertions(+) > > > > diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig > > index 449154f9a485..fece4c02b97c 100644 > > --- a/arch/arm64/kvm/Kconfig > > +++ b/arch/arm64/kvm/Kconfig > > @@ -103,5 +103,14 @@ config PKVM_STACKTRACE > > If unsure, or not using protected nVHE (pKVM), say N. > > > > endif # NVHE_EL2_DEBUG > > + > > +config KVM_ARM_SPE > > NIT: Nothing else in the file has the _ARM_ prefix, so is that redundant > here? I add the capability KVM_CAP_ARM_SPE later, so I would rather keep the config name KVM_ARM_SPE so the two align? > > > + bool > > + depends on KVM && ARM_SPE_PMU > > I think KVM should be removed here, this is within an 'if KVM' block > already, and nothing else here depends on it either so not a convention. Removed the explicit dependency on KVM. Thanks, Alex > > > + default n > > + help > > + Adds support for Statistical Profiling Extension (SPE) in virtual > > + machines. > > + > > endif # KVM > > endif # VIRTUALIZATION > > -- > > 2.43.0 > > > > > > -- > Cheers, Lorenzo