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 D4E93170822 for ; Tue, 17 Dec 2024 20:17:01 +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=1734466624; cv=none; b=EjCZJ8pHblBzfy9Fze/Tppi4HgJ2Bgl57aOdel/egrXlKtcqZ83GeRWzFKWme/TMmXHgAGPfam7jlhUN5ZP4XsbenZMQezUs9CprP/2H5hMskhCQVMlyK1lFwX0eMvWROKkpZkl/r3sy4uzVa87m5sSK5VLQ1JvHOTXCzqhh9kU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734466624; c=relaxed/simple; bh=pRypW7KH5HlUlUBUvd5v7lb41TTYS5LmMVimRkSAwU0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=tp1Xdf+XgIYVVjVyPfD3uHnGLmSuqghIokWLdcN6/IPkTBQfYMzV69QKbG6PdXoQRIWbMVG0NucznbvPdCjiI5Jzr3m26hK5cjc7ttjSOBszKXy5nAsi0OFERFq/8tHx2am+2AzT0LoN4fUrUNXMgvhXtNaE2JhAeE3GyVDrCpk= 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 082C9497; Tue, 17 Dec 2024 12:17:28 -0800 (PST) Received: from [172.27.42.65] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BF93F3F528; Tue, 17 Dec 2024 12:16:59 -0800 (PST) Message-ID: <8ef0a63c-bde2-443b-b2fd-59d24c5e18e6@arm.com> Date: Tue, 17 Dec 2024 14:16:59 -0600 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 v3 1/1] arm64: rsi: Add automatic arm-cca-guest module loading To: Itaru Kitayama Cc: linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com, gshan@redhat.com, steven.price@arm.com, sami.mujawar@arm.com, catalin.marinas@arm.com, will@kernel.org, linux-kernel@vger.kernel.org References: <20241207012128.247522-1-jeremy.linton@arm.com> <20241207012128.247522-2-jeremy.linton@arm.com> Content-Language: en-US From: Jeremy Linton In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi, On 12/7/24 10:38 PM, Itaru Kitayama wrote: > Hi Jeremy, > > On Fri, Dec 06, 2024 at 07:21:28PM -0600, Jeremy Linton wrote: >> The TSM module provides guest identification and attestation when a >> guest runs in CCA mode. By creating a dummy platform device, let's > > Perhaps could you spell out like; a guest runs in the Realm state? Thanks for looking at this. I thought that was evident from the rest of the commits here, but sure. Thanks again. > > Thanks, > Itaru. > >> 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 >> --- >> 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..5434e5496ac2 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 rsi_init(void) >> +{ >> + if (is_realm_world() && >> + platform_device_register(&rsi_dev)) >> + pr_err("failed to register rsi platform device\n"); >> + return 0; >> +} >> + >> +arch_initcall(rsi_init) >> 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"); >> -- >> 2.46.0 >>