[PATCH v2 02/12] x86/kexec/64: Forbid kexec when running as an SEV-ES guest

Joerg Roedel
2021-09-13T15:56:26Z

From: Joerg Roedel <jroedel@suse.de>

For now, kexec is not supported when running as an SEV-ES guest. Doing
so requires additional hypervisor support and special code to hand
over the CPUs to the new kernel in a safe way.

Until this is implemented, do not support kexec in SEV-ES guests.

Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
arch/x86/kernel/machine_kexec_64.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 131f30fdcfbd..a8e16a411b40 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -591,3 +591,11 @@ void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages)
*/
set_memory_encrypted((unsigned long)vaddr, pages);
}
+
+/*
+ * Kexec is not supported in SEV-ES guests yet
+ */
+bool arch_kexec_supported(void)
+{
+ return !sev_es_active();
+}
--
2.33.0