[PATCH v4 1/9] x86/kexec/64: Disable kexec when SEV-ES is active

From: Vasant Karasulli <vsntk18@gmail.com>
To: x86@kernel.org
Cc: joro@8bytes.org, cfir@google.com, dan.j.williams@intel.com,
	dave.hansen@linux.intel.com, ebiederm@xmission.com,
	erdemaktas@google.com, hpa@zytor.com, jgross@suse.com,
	jslaby@suse.cz, keescook@chromium.org, kexec@lists.infradead.org,
	kvm@vger.kernel.org, linux-coco@lists.linux.dev,
	linux-kernel@vger.kernel.org, luto@kernel.org,
	martin.b.radev@gmail.com, mhiramat@kernel.org,
	mstunes@vmware.com, nivedita@alum.mit.edu, peterz@infradead.org,
	rientjes@google.com, seanjc@google.com, stable@vger.kernel.org,
	thomas.lendacky@amd.com,
	virtualization@lists.linux-foundation.org,
	Joerg Roedel <jroedel@suse.de>,
	Vasant Karasulli <vkarasulli@suse.de>
Subject: [PATCH v4 1/9] x86/kexec/64: Disable kexec when SEV-ES is active
Date: Mon, 11 Mar 2024 17:17:19 +0100	[thread overview]
Message-ID: <20240311161727.14916-2-vsntk18@gmail.com> (raw)
In-Reply-To: <20240311161727.14916-1-vsntk18@gmail.com>

From: Joerg Roedel <jroedel@suse.de>

SEV-ES needs special handling to support kexec. Disable it when SEV-ES
is active until support is implemented.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Vasant Karasulli <vkarasulli@suse.de>
---
 arch/x86/kernel/machine_kexec_64.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index bc0a5348b4a6..3671ea1a5045 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -267,11 +267,22 @@ static void load_segments(void)
 		);
 }

+static bool machine_kexec_supported(void)
+{
+	if (cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT))
+		return false;
+
+	return true;
+}
+
 int machine_kexec_prepare(struct kimage *image)
 {
 	unsigned long start_pgtable;
 	int result;

+	if (!machine_kexec_supported())
+		return -ENOSYS;
+
 	/* Calculate the offsets */
 	start_pgtable = page_to_pfn(image->control_code_page) << PAGE_SHIFT;

--
2.34.1

