From nobody Mon Feb 9 07:43:05 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5EA5E74405; Thu, 4 Apr 2024 09:11:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712221880; cv=none; b=CoPCT5nJSAP5MvVIMn3Qqv2wWr+9mZRMzp63uApNtcDgLGOpd8Bsate1HPU5jAl211T5XJ9Whx/RgGnFKBE8716hfpIUJwgALkz7eCkBmwXYpLjr/mK0xmXCJ9Z3mW0XPKUZgQGxCaNF0VNflfq0yqutkzneQ7GrDypaF31JQb8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712221880; c=relaxed/simple; bh=sSiAHnCYkMAb41uzqPX+bVFr0C/dLkqAWl3jCy0fZ9Q=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=mkfdWzp+Ohku23/GTibG9Dh598U/Lc1cGO3jwfunhPfydKXiBzPGG1njk2vyI+GpByELJikpl6UuZtRmL7VIbpcdRfYXjStxWUV1U3QpbFBsCLvFpI9rvYmY4BD55TREGCovqJdYB3yzfZ+vY3Y2ht76fajeQ8+iAodXKe4M3D0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=lPhqarTD; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=TIDrA7tY; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="lPhqarTD"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="TIDrA7tY" Date: Thu, 04 Apr 2024 09:11:15 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1712221876; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O+LRvHTpnOJnw49qH5A279TkC00i92hA34WqJSFN1GI=; b=lPhqarTD0ara8iv/wt6nADF9NK1k0j7bmvEQn3Qruo3VLMRrkQR8nk9aew383NsJZRgM0e 7K5WqksXS+7g9f/KpVs2t9crI5q5/g6s77hMaK8Wpkbgrlt2UdZu8PuU8nFElamPwsMgZ0 enq8kLKjE1pPk77DvSp0cJwQ15rmeHLtBWU4H8touyK06zl5xXz+3QW44Y5NLfTFBVKnUG QJwavA367GfwuxTtkXgVhAcpBeH9DCbfUS/I0iZpCXTsFlE24dgXO9Aq/nprjH5Exiic6x cEw2YXbfKbaGalC622t4uxudhX5s/cma6JJy9vQMi82ilXJCnBnKAZQG1MJnTA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1712221876; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O+LRvHTpnOJnw49qH5A279TkC00i92hA34WqJSFN1GI=; b=TIDrA7tYCHfeSiemTWu3K0BVuz2g/hQNHPMCCur9/H97ylxfXlm5Af+2VON1PjTjXnV+tS HnEvrc8kt55ofJDA== From: "tip-bot2 for Borislav Petkov (AMD)" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/urgent] x86/cc: Add cc_platform_set/_clear() helpers Cc: "Borislav Petkov (AMD)" , Tom Lendacky , Srikanth Aithal , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20240327154317.29909-5-bp@alien8.de> References: <20240327154317.29909-5-bp@alien8.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <171222187533.10875.12139303211259990842.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the x86/urgent branch of tip: Commit-ID: bc6f707fc0feec72acc2f49c312eb31d257363a3 Gitweb: https://git.kernel.org/tip/bc6f707fc0feec72acc2f49c312eb31d2= 57363a3 Author: Borislav Petkov (AMD) AuthorDate: Wed, 27 Mar 2024 16:43:16 +01:00 Committer: Borislav Petkov (AMD) CommitterDate: Thu, 04 Apr 2024 10:40:27 +02:00 x86/cc: Add cc_platform_set/_clear() helpers Add functionality to set and/or clear different attributes of the machine as a confidential computing platform. Add the first one too: whether the machine is running as a host for SEV-SNP guests. Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support") Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Tom Lendacky Tested-by: Srikanth Aithal Link: https://lore.kernel.org/r/20240327154317.29909-5-bp@alien8.de --- arch/x86/coco/core.c | 52 ++++++++++++++++++++++++++++++++++++- include/linux/cc_platform.h | 12 ++++++++- 2 files changed, 64 insertions(+) diff --git a/arch/x86/coco/core.c b/arch/x86/coco/core.c index ddd4efd..b31ef24 100644 --- a/arch/x86/coco/core.c +++ b/arch/x86/coco/core.c @@ -20,6 +20,11 @@ enum cc_vendor cc_vendor __ro_after_init =3D CC_VENDOR_NONE; u64 cc_mask __ro_after_init; =20 +static struct cc_attr_flags { + __u64 host_sev_snp : 1, + __resv : 63; +} cc_flags; + static bool noinstr intel_cc_platform_has(enum cc_attr attr) { switch (attr) { @@ -93,6 +98,9 @@ static bool noinstr amd_cc_platform_has(enum cc_attr attr) case CC_ATTR_GUEST_SEV_SNP: return sev_status & MSR_AMD64_SEV_SNP_ENABLED; =20 + case CC_ATTR_HOST_SEV_SNP: + return cc_flags.host_sev_snp; + default: return false; } @@ -153,6 +161,50 @@ u64 cc_mkdec(u64 val) } EXPORT_SYMBOL_GPL(cc_mkdec); =20 +static void amd_cc_platform_clear(enum cc_attr attr) +{ + switch (attr) { + case CC_ATTR_HOST_SEV_SNP: + cc_flags.host_sev_snp =3D 0; + break; + default: + break; + } +} + +void cc_platform_clear(enum cc_attr attr) +{ + switch (cc_vendor) { + case CC_VENDOR_AMD: + amd_cc_platform_clear(attr); + break; + default: + break; + } +} + +static void amd_cc_platform_set(enum cc_attr attr) +{ + switch (attr) { + case CC_ATTR_HOST_SEV_SNP: + cc_flags.host_sev_snp =3D 1; + break; + default: + break; + } +} + +void cc_platform_set(enum cc_attr attr) +{ + switch (cc_vendor) { + case CC_VENDOR_AMD: + amd_cc_platform_set(attr); + break; + default: + break; + } +} + __init void cc_random_init(void) { /* diff --git a/include/linux/cc_platform.h b/include/linux/cc_platform.h index cb0d6cd..60693a1 100644 --- a/include/linux/cc_platform.h +++ b/include/linux/cc_platform.h @@ -90,6 +90,14 @@ enum cc_attr { * Examples include TDX Guest. */ CC_ATTR_HOTPLUG_DISABLED, + + /** + * @CC_ATTR_HOST_SEV_SNP: AMD SNP enabled on the host. + * + * The host kernel is running with the necessary features + * enabled to run SEV-SNP guests. + */ + CC_ATTR_HOST_SEV_SNP, }; =20 #ifdef CONFIG_ARCH_HAS_CC_PLATFORM @@ -107,10 +115,14 @@ enum cc_attr { * * FALSE - Specified Confidential Computing attribute is not active */ bool cc_platform_has(enum cc_attr attr); +void cc_platform_set(enum cc_attr attr); +void cc_platform_clear(enum cc_attr attr); =20 #else /* !CONFIG_ARCH_HAS_CC_PLATFORM */ =20 static inline bool cc_platform_has(enum cc_attr attr) { return false; } +static inline void cc_platform_set(enum cc_attr attr) { } +static inline void cc_platform_clear(enum cc_attr attr) { } =20 #endif /* CONFIG_ARCH_HAS_CC_PLATFORM */