From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=13.77.154.182 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793647653; b=bQAq6Ix7Ec7N5Vk4rKZ8cRotb51PlliUg4xrP60QCOVPGcRshCO8uaF7DJIgQLVWTMiL nPdTzj/DcDv1RLFaiZqv84SNt86a4xDsVHS1HY2SZ5HG2PKutJOLsJzMlTq7CIvYcDrrh aw06S9xKbDKxpwvBqjCmvkdMyACcN9A15VkWY3KV5ASo7g6AdJVJFQCpuy3G3fqXQb6pS JVHewwn3tuuUvB4mke2rD02ekvYbm+DyvDpNvtWxtpSIABy0Yh1PHQmwAAV8UDE2qVxXa rnpPmtz2ccZS2HnzchgcMCtYOrVNRVGGkRegdxLvx70/E1NprauZxWnPkGa8wMOZArg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793647653; h=DMARC-Filter:Received:DKIM-Filter:DKIM-Signature:Message-ID:Date: MIME-Version:User-Agent:Subject:To:Cc:References:Content-Language: From:In-Reply-To:Content-Type:Content-Transfer-Encoding:X-Spam-Status: X-Spam-Checker-Version; bh=9R7rn27BTvQI3HlJKKfu8p/MBYgn8iEr6X7HO0Xk9Xo=; b=NxC8TpgXNmqOmNjtr86gbeUjMiZTHIVjFhgiOlDpj3LKLaNMXulSL/WN30LGifgcS8YY sgOmJCx+ZagR6FBrqC4aSY/OAsBZ9YzPO6LXs6Xhp4vQTSxgzyMMAGNAxajpZqSAxj1je CKXB4XXL2GEnEbHDagHnhdpIFgBd8pRVtLEfQLGHpNgSiKoxn41vu2AZ83Q9sOfKLFDcc uhsErk1xthQA+xOBxpVraYZzzLWBo0k3et41BWkWPrnSUacdjyM49Bwhw3p1O6/KCBlTb GxGSDripRBue9AKPIwZjPYps7jBdAExyd3ZTZa3Jj4Vf1GAEIdaXelM7vho4Mvlbddg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass header.d=linux.microsoft.com header.i=@linux.microsoft.com header.a=rsa-sha256 header.s=default header.b=TO39YtUd; arc=none smtp.remote-ip=13.77.154.182 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 57792606A326; Mon, 2 Nov 2026 19:27:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 57792606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.a=rsa-sha256 header.s=default header.b=TO39YtUd Received: from [10.4.158.9] (unknown [131.107.174.137]) by linux.microsoft.com (Postfix) with ESMTPSA id 6549D20B7166; Mon, 2 Nov 2026 11:27:18 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 6549D20B7166 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1793647638; bh=9R7rn27BTvQI3HlJKKfu8p/MBYgn8iEr6X7HO0Xk9Xo=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=TO39YtUd3Cf/StF0QdPN6j/y4FbKs8B4iukuDInUIKTsVQ1LEzXCfdknb5uZ9yR6g 3ho611vKzzuwp3vFYIg+aRD3vGJGC8lACS0ButV7faA5pYvf3tsTfix5VvL1wLluTa L28VqbIrKkdSC4GVW4GL5tz22IwvjhYGEzwbQOdg= Message-ID: Date: Mon, 2 Nov 2026 11:27:37 -0800 X-Mailing-List: linux-arch@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 2/6] arm64: hyperv: Detect Hyper-V via RSI host call in CCA Realms To: Catalin Marinas Cc: decui@microsoft.com, haiyangz@microsoft.com, mhklinux@outlook.com, wei.liu@kernel.org, arnd@arndb.de, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, lpieralisi@kernel.org, mark.rutland@arm.com, sudeep.holla@kernel.org, thuth@redhat.com, will@kernel.org References: <20261031001412.4150488-1-kameroncarr@linux.microsoft.com> <20261031001412.4150488-3-kameroncarr@linux.microsoft.com> Content-Language: en-US From: Kameron Carr In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/2/2026 4:12 AM, Catalin Marinas wrote: > On Fri, Oct 30, 2026 at 05:14:08PM -0700, Kameron Carr wrote: >> When booting without ACPI, hyperv_detect_via_smccc() detects Hyper-V by >> querying the SMCCC vendor hypervisor UID. In an Arm CCA Realm the SMCCC >> call is handled by the RMM rather than by the hypervisor, so the >> query never reaches Hyper-V and detection fails. >> >> When running in a Realm, forward ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID >> to the host with RSI_HOST_CALL instead, which is how Hyper-V hypercalls >> are issued from a Realm. >> >> This is done in the Hyper-V code rather than in the generic >> arm_smccc_hypervisor_has_uuid() because the other users expect different >> behavior. >> >> hyperv_init() is an early_initcall and runs before the secondary CPUs >> are brought up, so a single __initdata host call structure is used >> without locking. >> >> ACPI-based detection and non-Realm guests are unaffected. >> >> Signed-off-by: Kameron Carr > > This works for me, thanks. I replied to Dexuan clarifying my objection > to v5 do the UUID check generically. Thank you for your review and suggestions. Your clarification makes sense. Is this a "Reviewed-by" or an "Acked-by"? -- Regards, Kameron