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 15F7C18C924 for ; Mon, 23 Dec 2024 09:32:38 +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=1734946362; cv=none; b=k2X+/EPo7tEinORx9UeDoVCWB3wV/QAGm5ZYZ9gDXK64ddv1CQcolSpjj4bMDEj9oIsV1orrxBE09qMHwtg9ypzFO39ikNNolf+tIBTiyKcHWtkmLyGahZj0iSmBxbK1LXY2gJ2PEZl0iqZtpqHOs1xW3DzI7OFLBg0WDDRcoRg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734946362; c=relaxed/simple; bh=Ir6fhaZtfNVCLWaP0xdJmUGIa8tW11Qp1+UXYilrSp4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=LrHGBc+VfOsKmGt/LHVPTPl47kt+vc8vsEK4evkD/taFVGMIkrHsyzs7dI92V/DKkO3AaYO9oaOYlKOzia8dgEb0hLxxrItdZraODj+xtCpBCRJYSGBdHthxEM1ajSowc5NUoqVHBBC/dAVRromWZnfafN6rVJdoa7WUj1uVY9o= 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 5E1D3152B; Mon, 23 Dec 2024 01:33:00 -0800 (PST) Received: from [10.57.73.219] (unknown [10.57.73.219]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 692B23F58B; Mon, 23 Dec 2024 01:32:30 -0800 (PST) Message-ID: Date: Mon, 23 Dec 2024 09:32:28 +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 v4 1/1] arm64: rsi: Add automatic arm-cca-guest module loading To: Jeremy Linton , linux-arm-kernel@lists.infradead.org Cc: suzuki.poulose@arm.com, gshan@redhat.com, sami.mujawar@arm.com, itaru.kitayama@linux.dev, catalin.marinas@arm.com, will@kernel.org, linux-kernel@vger.kernel.org References: <20241220181236.172060-1-jeremy.linton@arm.com> <20241220181236.172060-2-jeremy.linton@arm.com> From: Steven Price Content-Language: en-GB In-Reply-To: <20241220181236.172060-2-jeremy.linton@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 20/12/2024 18:12, Jeremy Linton wrote: > The TSM module provides guest identification and attestation when a > guest runs in CCA realm mode. By creating a dummy platform device, > let's ensure the module is automatically loaded. The udev daemon loads > the TSM module after it receives a device addition event. Once that > happens, it can be used earlier in the boot process to decrypt the > rootfs. > > Signed-off-by: Jeremy Linton > Reviewed-by: Gavin Shan LGTM Reviewed-by: Steven Price Thanks, Steve > --- > arch/arm64/include/asm/rsi.h | 2 ++ > arch/arm64/kernel/rsi.c | 15 +++++++++++++++ > drivers/virt/coco/arm-cca-guest/arm-cca-guest.c | 8 ++++++++ > 3 files changed, 25 insertions(+) > > diff --git a/arch/arm64/include/asm/rsi.h b/arch/arm64/include/asm/rsi.h > index 188cbb9b23f5..b42aeac05340 100644 > --- a/arch/arm64/include/asm/rsi.h > +++ b/arch/arm64/include/asm/rsi.h > @@ -10,6 +10,8 @@ > #include > #include > > +#define RSI_PDEV_NAME "arm-cca-dev" > + > DECLARE_STATIC_KEY_FALSE(rsi_present); > > void __init arm64_rsi_init(void); > diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c > index 3031f25c32ef..ce4778141ec7 100644 > --- a/arch/arm64/kernel/rsi.c > +++ b/arch/arm64/kernel/rsi.c > @@ -8,6 +8,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -140,3 +141,17 @@ void __init arm64_rsi_init(void) > static_branch_enable(&rsi_present); > } > > +static struct platform_device rsi_dev = { > + .name = RSI_PDEV_NAME, > + .id = PLATFORM_DEVID_NONE > +}; > + > +static int __init arm64_create_dummy_rsi_dev(void) > +{ > + if (is_realm_world() && > + platform_device_register(&rsi_dev)) > + pr_err("failed to register rsi platform device\n"); > + return 0; > +} > + > +arch_initcall(arm64_create_dummy_rsi_dev) > diff --git a/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c b/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c > index 488153879ec9..87f162736b2e 100644 > --- a/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c > +++ b/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c > @@ -6,6 +6,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -219,6 +220,13 @@ static void __exit arm_cca_guest_exit(void) > } > module_exit(arm_cca_guest_exit); > > +/* modalias, so userspace can autoload this module when RSI is available */ > +static const struct platform_device_id arm_cca_match[] __maybe_unused = { > + { RSI_PDEV_NAME, 0}, > + { } > +}; > + > +MODULE_DEVICE_TABLE(platform, arm_cca_match); > MODULE_AUTHOR("Sami Mujawar "); > MODULE_DESCRIPTION("Arm CCA Guest TSM Driver"); > MODULE_LICENSE("GPL");