From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 7FC7A47BCE8; Thu, 8 Jan 2026 14:23:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767882198; cv=none; b=n+ORWQ2JMwbNrKaD43UVQU6KUfkqLs5PCHpS+8/11iK0it9YFB0MNGK8WSJG7vTsHRCz4EXBHfjWltLtHs65Ee7iuWhm3zaUGQaJPlE31/EplnwbjJuvHp4WFsZbJPWLEAwxLuQJWiejnu0je9YTZvKyeGHXUly9juz+Ru+cr9g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767882198; c=relaxed/simple; bh=zp/83stCCwa0ccWfXiPgYHVgHpqygUIPCOZUndMQGfc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Nwkt3fKIJO3q+arRM2ulCco1CUrJZrwWpsvuu5Dypo+TyzAYzfytNrFCHsxp/o7TgNn/7HrfeSsUr9bDYEeljdbF+zX4nGdF0bYopvioKwBexTF1rQdF4s32jsz8M543UOQIgSYxbQqT2lCiclqq+8//wVlF7X2veysSgsr0YUg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 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 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 89F34497; Thu, 8 Jan 2026 06:23:03 -0800 (PST) Received: from [10.57.67.29] (unknown [10.57.67.29]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 88CB23F5A1; Thu, 8 Jan 2026 06:23:07 -0800 (PST) Message-ID: <6afdf188-a82e-4c46-a518-8d007cc85d23@arm.com> Date: Thu, 8 Jan 2026 14:23:04 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH kvmtool v4 15/15] arm64: smccc: Start sending PSCI to userspace Content-Language: en-GB To: Marc Zyngier Cc: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, will@kernel.org, oliver.upton@linux.dev, alexandru.elisei@arm.com, aneesh.kumar@kernel.org, steven.price@arm.com, tabba@google.com References: <20250930103130.197534-1-suzuki.poulose@arm.com> <20250930103130.197534-17-suzuki.poulose@arm.com> <86344gmbtb.wl-maz@kernel.org> From: Suzuki K Poulose In-Reply-To: <86344gmbtb.wl-maz@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 08/01/2026 14:14, Marc Zyngier wrote: > On Tue, 30 Sep 2025 11:31:30 +0100, > Suzuki K Poulose wrote: >> >> From: Oliver Upton >> >> kvmtool now has a PSCI implementation that complies with v1.0 of the >> specification. Use the SMCCC filter to start sending these calls out to >> userspace for further handling. While at it, shut the door on the >> legacy, KVM-specific v0.1 functions. >> >> Signed-off-by: Oliver Upton >> Signed-off-by: Suzuki K Poulose >> --- >> arm64/include/kvm/kvm-config-arch.h | 8 +++++-- >> arm64/smccc.c | 37 +++++++++++++++++++++++++++++ >> 2 files changed, 43 insertions(+), 2 deletions(-) >> >> diff --git a/arm64/include/kvm/kvm-config-arch.h b/arm64/include/kvm/kvm-config-arch.h >> index ee031f01..3158fadf 100644 >> --- a/arm64/include/kvm/kvm-config-arch.h >> +++ b/arm64/include/kvm/kvm-config-arch.h >> @@ -15,6 +15,7 @@ struct kvm_config_arch { >> u64 fw_addr; >> unsigned int sve_max_vq; >> bool no_pvtime; >> + bool in_kernel_smccc; >> }; >> >> int irqchip_parser(const struct option *opt, const char *arg, int unset); >> @@ -52,11 +53,14 @@ int sve_vl_parser(const struct option *opt, const char *arg, int unset); >> "Force virtio devices to use PCI as their default " \ >> "transport (Deprecated: Use --virtio-transport " \ >> "option instead)", virtio_transport_parser, kvm), \ >> - OPT_CALLBACK('\0', "irqchip", &(cfg)->irqchip, \ >> + OPT_CALLBACK('\0', "irqchip", &(cfg)->irqchip, \ >> "[gicv2|gicv2m|gicv3|gicv3-its]", \ >> "Type of interrupt controller to emulate in the guest", \ >> irqchip_parser, NULL), \ >> OPT_U64('\0', "firmware-address", &(cfg)->fw_addr, \ >> - "Address where firmware should be loaded"), >> + "Address where firmware should be loaded"), \ >> + OPT_BOOLEAN('\0', "in-kernel-smccc", &(cfg)->in_kernel_smccc, \ >> + "Disable userspace handling of SMCCC, instead" \ >> + " relying on the in-kernel implementation"), >> > > nit: this really is about PSCI, not SMCCC. The fact that we use the > SMCCC interface to route PSCI calls is an implementation detail, > really. The other thing is that this is a change in default behaviour, > and I'd rather keep in-kernel PSCI to be the default, specially given > that this otherwise silently fails on old kernels. > Agreed, I will address this. > To that effect, I'd suggest the following instead: > > + OPT_BOOLEAN('\0', "psci", &(cfg)->userspace_psci, \ > + "Request userspace handling of PSCI, instead" \ > + " relying on the in-kernel implementation"), > > and the code modified accordingly. > Cheers Suzuki