From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 3D45F14C5B3; Thu, 16 May 2024 15:27:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715873239; cv=none; b=av5yTqMVOfMd6mTF9LyH438zu5cAnj1g6OQekExyNFk76d1/VLtpVNez3jmX4YS6xF2rpRHkCvzzIIj6T0I+xxMdEZxA6LVoS1IUDzZVF8TlIVl7ufP/1M8V/PhinVIQoq6UFb0NrCs0FzIY7LM/kNHcGG+TXksM04XzBcYBKXg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715873239; c=relaxed/simple; bh=BccJ0HF5Illb00Em11qtCvLHarKzg0ooqw7/HcoSL9A=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=iPp5X7vOfhikA3TRzw8U6OT8K+VxH/wYJUKa0XDgUshnSnl9o2JRKogaACZOr0hWFQVY2994R6n11WkYwN37MnDVP5UOHKJmh2YgHiEDN2b4oSLqMuos1G/tFV/f72L2HhrLWN7cx9OQpQtDpw5bJ2mcpm6AEWnTzNFuHy0RHug= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=JzU6VQwP; arc=none smtp.client-ip=13.77.154.182 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) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="JzU6VQwP" Received: from [10.137.186.190] (unknown [131.107.159.62]) by linux.microsoft.com (Postfix) with ESMTPSA id 5FC4B20B915A; Thu, 16 May 2024 08:27:12 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 5FC4B20B915A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1715873232; bh=VYw2CBFjzoPTujslbESLr1CJ6eokJI9FsmFec2GE+5Y=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=JzU6VQwPnDgbMyagVyu7XqnShkR+OoIMv1PiyI6c8vySazBXPTP89U3QX55rMeN9P eiLb6A/YK7IWrQgnf8XdBiCzyCtDgr2Dgi8M/N05AinyH7IlTmsfRCLFfFRAmVOAAt YU54Hr3Y0apONAux+8AwswlIiJfpZ8lltciPPiDc= Message-ID: <9b216f16-a2ea-48d7-8986-f0c2e3f3d009@linux.microsoft.com> Date: Thu, 16 May 2024 08:27:12 -0700 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/6] arm64/hyperv: Support DeviceTree To: Elliot Berman Cc: arnd@arndb.de, bhelgaas@google.com, bp@alien8.de, catalin.marinas@arm.com, dave.hansen@linux.intel.com, decui@microsoft.com, haiyangz@microsoft.com, hpa@zytor.com, kw@linux.com, kys@microsoft.com, lenb@kernel.org, lpieralisi@kernel.org, mingo@redhat.com, mhklinux@outlook.com, rafael@kernel.org, robh@kernel.org, tglx@linutronix.de, wei.liu@kernel.org, will@kernel.org, linux-acpi@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, ssengar@microsoft.com, sunilmut@microsoft.com, vdso@hexbites.dev References: <20240514224508.212318-1-romank@linux.microsoft.com> <20240514224508.212318-2-romank@linux.microsoft.com> <20240515143359142-0700.eberman@hu-eberman-lv.qualcomm.com> Content-Language: en-US From: Roman Kisel In-Reply-To: <20240515143359142-0700.eberman@hu-eberman-lv.qualcomm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 5/15/2024 3:02 PM, Elliot Berman wrote: > On Tue, May 14, 2024 at 03:43:48PM -0700, Roman Kisel wrote: >> The Virtual Trust Level platforms rely on DeviceTree, and the >> arm64/hyperv code supports ACPI only. Update the logic to >> support DeviceTree on boot as well as ACPI. > > Could you use Call UID query from SMCCC? KVM [1] and Gunyah [2] have > been using this to identify if guest is running under those respective > hypervisors. This works in both DT and ACPI cases. > > [1]: https://lore.kernel.org/all/20210330145430.996981-2-maz@kernel.org/ > [2]: https://lore.kernel.org/all/20240222-gunyah-v17-4-1e9da6763d38@quicinc.com/ That would be very neat indeed, thanks! Talking to the hypervisor folks. >> >> Signed-off-by: Roman Kisel >> --- >> arch/arm64/hyperv/mshyperv.c | 34 +++++++++++++++++++++++++++++----- >> 1 file changed, 29 insertions(+), 5 deletions(-) >> >> diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c >> index b1a4de4eee29..208a3bcb9686 100644 >> --- a/arch/arm64/hyperv/mshyperv.c >> +++ b/arch/arm64/hyperv/mshyperv.c >> @@ -15,6 +15,9 @@ >> #include >> #include >> #include >> +#include >> +#include >> +#include >> #include >> >> static bool hyperv_initialized; >> @@ -27,6 +30,29 @@ int hv_get_hypervisor_version(union hv_hypervisor_version_info *info) >> return 0; >> } >> >> +static bool hyperv_detect_fdt(void) >> +{ >> +#ifdef CONFIG_OF >> + const unsigned long hyp_node = of_get_flat_dt_subnode_by_name( >> + of_get_flat_dt_root(), "hypervisor"); >> + >> + return (hyp_node != -FDT_ERR_NOTFOUND) && >> + of_flat_dt_is_compatible(hyp_node, "microsoft,hyperv"); >> +#else >> + return false; >> +#endif >> +} >> + >> +static bool hyperv_detect_acpi(void) >> +{ >> +#ifdef CONFIG_ACPI >> + return !acpi_disabled && >> + !strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8); >> +#else >> + return false; >> +#endif >> +} >> + >> static int __init hyperv_init(void) >> { >> struct hv_get_vp_registers_output result; >> @@ -35,13 +61,11 @@ static int __init hyperv_init(void) >> >> /* >> * Allow for a kernel built with CONFIG_HYPERV to be running in >> - * a non-Hyper-V environment, including on DT instead of ACPI. >> + * a non-Hyper-V environment. >> + * >> * In such cases, do nothing and return success. >> */ >> - if (acpi_disabled) >> - return 0; >> - >> - if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8)) >> + if (!hyperv_detect_fdt() && !hyperv_detect_acpi()) >> return 0; >> >> /* Setup the guest ID */ >> -- >> 2.45.0 >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Thank you, Roman