From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.140.110.172 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794503935; b=dvVnJ4ZoG/9HIZnfpUIFgUnLB+rsR97UiJ3bSDDnrMah247XHI351noA4VEqLTzA4aSN jTWRf3iPj8xJA4Xzox5DB5fdK0UUFcgWiZRGp5gTKGqrehwgD5G2WJ8D6e3n4A0zSvC7b M6Mvzaxa+DAVdUNXBeiuy8fVeq0pKkFLlNmjB6qniv22ATjZOOSYPkhE1RqM6lKY+OTM7 M7bziylYmwTugKOKbfaCn29nTdMI4Qj/p/OTUBVvaySjPpmDEI7QOZGn4snJLLUJmJ5p2 iJg8ulvT6/rEAFIUQtOcufJUF/qvqY0FncTtXP/xAVKtkKAVG/W87b1xQF8vSzabLnA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794503935; h=DMARC-Filter:Received:Received:DKIM-Signature:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; bh=BlY58mh9Hw/tgSMH5z15/+c8H0ljlIKjWB31zCng0sM=; b=1vrUiRhCzln8ORteGjlAUjAwbLH6I8j+Yx6GXAfTBBpzqrZJV3Po8jLWLu2EarfFc799 cWvLptfZNl4QGoJ6M12hGhCbasdUZAWYfYUdefb4pR+MIc9xJYhoKa533oAkiKvzquGOT TXRbK4yWf3NY2HHat3rVy6lwIgcdWRDbzlJ3+Tgx5Cyd3MvQlorftgRvQRSxyg1T9PyCJ BK44hGEIFi6cF6qjnvnBgg9lmCSR0mM1Md90W0dKDZzjnD44FuJuQjOasz0y0mJnimRHv /TV+xMkZqTml/pMoJV8w5ZYqPQ2E7ENJHka/CD2y1BoiVCzMLKKGdbmakmjT2xWVUIw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b="u/Jt9bDL"; arc=none smtp.remote-ip=217.140.110.172 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CB82A606A327 for ; Thu, 12 Nov 2026 17:18:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org CB82A606A327 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=u/Jt9bDL 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 305411516; Thu, 12 Nov 2026 09:18:51 -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 EE7693F632; Thu, 12 Nov 2026 09:18:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794503934; bh=PMnroKYZu+m0u0h/6B9jMwGrR1fmbzde9UqBEKf/0sA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=u/Jt9bDLrv1f6QNL1AEOhElHFgK1s4fLaLHscOU9PjRzYui4BbMl8SJka2h6VikLY WJNC5gWbUoj1lZkjG+3kKbiM+UE2gl1/nt0oVpl+q+zL1RUd5J1qTihCq3E8Y5acfI Rkht22WSzistnaD4kF7Nya7bqy8yDEr6UcYYWwb8= Date: Thu, 12 Nov 2026 17:18:49 +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 07/28] KVM: arm64: Add KVM_ARM_VCPU_SPE VCPU feature Message-ID: References: <20260903160623.315525-1-alexandru.elisei@arm.com> <20260903160623.315525-8-alexandru.elisei@arm.com> X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hi Lorenzo, On Fri, Oct 16, 2026 at 03:23:57PM +0100, Lorenzo Stoakes (ARM) wrote: > On Thu, Sep 03, 2026 at 05:06:02PM +0100, Alexandru Elisei wrote: > > Add a new VCPU feature that enables SPE virtualization when set by > > userspace. KVM_VCPU_MAX_FEATURE will be bumped and the feature will > > become selectable by userspace once SPE support in KVM is implemented. > > I guess it's also limited currently at this point in the series by > KVM_CAP_ARM_SPE being unselectable as it stands I think? Yes, indirectly - KVM_CAP_ARM_SPE is advertised only when kvm_supports_spe() is true, and KVM_ARM_VCPU_SPE also depends on kvm_supports_spe(). CONFIG_KVM_ARM_SPE=y is required, but not sufficient, for kvm_supports_spe() to be true. So all of this depends on the Kconfig option, maybe I should document that in the capability doc. > > Maybe worth mentioning here that you're adding KVM_ARM_VPCU_SPE to the uapi, > updating docs, etc.? I can mention it, but the short diff should speak for itself? > > > > > Signed-off-by: Alexandru Elisei > > I wonder if there are any dependencies that need expressing in > arch/arm64/kvm/config.c? > > In any case all LGTM, with mega-nit below addressed :): > > Reviewed-by: Lorenzo Stoakes (ARM) > > > --- > > Documentation/virt/kvm/api.rst | 2 ++ > > arch/arm64/include/asm/kvm_spe.h | 5 +++++ > > arch/arm64/include/uapi/asm/kvm.h | 1 + > > arch/arm64/kvm/arm.c | 7 +++++++ > > 4 files changed, 15 insertions(+) > > > > diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst > > index 1ed5c389c7a4..654736fac78c 100644 > > --- a/Documentation/virt/kvm/api.rst > > +++ b/Documentation/virt/kvm/api.rst > > @@ -3591,6 +3591,8 @@ Possible features: > > Depends on KVM_CAP_ARM_EL2_E2H0. > > KVM_ARM_VCPU_HAS_EL2 must also be set. > > > > + - KVM_ARM_VCPU_SPE: Enable SPE for the CPU. Depends on KVM_CAP_ARM_SPE. > > Super nitty, sorry, but it seems other parts of the docs use tabs, whereas this > uses spaces? Fixed. Thanks, Alex