From f2867b873653dd88d2882f122a28ccace0cb8e7c Mon Sep 17 00:00:00 2001
From: John Baldwin <jhb@FreeBSD.org>
Date: Fri, 22 Nov 2024 13:06:48 -0500
Subject: [PATCH] vmm: Don't trap access to Morello instructions for guests

---
 sys/arm64/vmm/vmm_reset.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/sys/arm64/vmm/vmm_reset.c b/sys/arm64/vmm/vmm_reset.c
index a55c50b2f3dd..bb8867e7fdef 100644
--- a/sys/arm64/vmm/vmm_reset.c
+++ b/sys/arm64/vmm/vmm_reset.c
@@ -181,6 +181,13 @@ reset_vm_el2_regs(void *vcpu)
 		el2ctx->cptr_el2 = CPTR_E2H_TRAP_ALL | CPTR_E2H_FPEN;
 	else
 		el2ctx->cptr_el2 = CPTR_TRAP_ALL & ~CPTR_TFP;
+#if __has_feature(capabilities)
+	/* Don't trap accesses to capability registers. */
+	if (in_vhe())
+		el2ctx->cptr_el2 |= CPTR_E2H_CEN;
+	else
+		el2ctx->cptr_el2 &= ~CPTR_TC;
+#endif
 	el2ctx->cptr_el2 &= ~CPTR_TCPAC;
 	/*
 	 * Disable interrupts in the guest. The guest OS will re-enable