From 5c3131c392f84c660033d511ec39872d8beb4b1e Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 18 Mar 2024 14:41:10 -0400
Subject: KVM: track whether guest state is encrypted
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So far, KVM has allowed KVM_GET/SET_* ioctls to execute even if the
guest state is encrypted, in which case they do nothing.  For the new
API using VM types, instead, the ioctls will fail which is a safer and
more robust approach.

The new API will be the only one available for SEV-SNP and TDX, but it
is also usable for SEV and SEV-ES.  In preparation for that, require
architecture-specific KVM code to communicate the point at which guest
state is protected (which must be after kvm_cpu_synchronize_post_init(),
though that might change in the future in order to suppor migration).
From that point, skip reading registers so that cpu->vcpu_dirty is
never true: if it ever becomes true, kvm_arch_put_registers() will
fail miserably.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/sev.c | 1 +
 1 file changed, 1 insertion(+)

(limited to 'target/i386')

diff --git a/target/i386/sev.c b/target/i386/sev.c
index b8f79d3..c49a8fd 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -755,6 +755,7 @@ sev_launch_get_measure(Notifier *notifier, void *unused)
         if (ret) {
             exit(1);
         }
+        kvm_mark_guest_state_protected();
     }
 
     /* query the measurement blob length */
-- 
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