From 92a5199b29f6519aa5f774f4b96dc41954f641d1 Mon Sep 17 00:00:00 2001
From: Tom Lendacky
Date: Tue, 26 Jan 2021 11:36:47 -0600
Subject: sev/i386: Don't allow a system reset under an SEV-ES guest

An SEV-ES guest does not allow register state to be altered once it has
been measured. When an SEV-ES guest issues a reboot command, Qemu will
reset the vCPU state and resume the guest. This will cause failures under
SEV-ES. Prevent that from occuring by introducing an arch-specific
callback that returns a boolean indicating whether vCPUs are resettable.

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: David Hildenbrand <david@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com>
Message-Id: <1ac39c441b9a3e970e9556e1cc29d0a0814de6fd.1611682609.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/ppc/kvm.c | 5 +++++
 1 file changed, 5 insertions(+)

(limited to 'target/ppc')

diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index 0c5056dd5b..298c1f882c 100644
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -2929,3 +2929,8 @@ void kvmppc_set_reg_tb_offset(PowerPCCPU *cpu, int64_t tb_offset)
         kvm_set_one_reg(cs, KVM_REG_PPC_TB_OFFSET, &tb_offset);
     }
 }
+
+bool kvm_arch_cpu_check_are_resettable(void)
+{
+    return true;
+}
-- 
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