From ab4c36c83498a9ef921adfd50ad71fc7d02bfc6a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Josef=20S=C3=B6ntgen?= <josef.soentgen@genode-labs.com>
Date: Thu, 31 Aug 2023 17:08:51 +0200
Subject: [PATCH] virtualbox6: wait at least 1 ms during halt

When the wait value is too small the HALT attempt turnes into
busy-polling in the VMM. To prevent that always wait a minimal
amount of time.

Issue #4990.
---
 repos/ports/src/virtualbox6/sup_vcpu.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/repos/ports/src/virtualbox6/sup_vcpu.cc b/repos/ports/src/virtualbox6/sup_vcpu.cc
index e7f782d648..f1196b3b27 100644
--- a/repos/ports/src/virtualbox6/sup_vcpu.cc
+++ b/repos/ports/src/virtualbox6/sup_vcpu.cc
@@ -721,7 +721,10 @@ template <typename VIRT> VBOXSTRICTRC Sup::Vcpu_impl<VIRT>::_switch_to_hw()
 
 template <typename T> void Sup::Vcpu_impl<T>::halt(Genode::uint64_t const wait_ns)
 {
-	RTSemEventMultiWait(_halt_semevent, wait_ns/RT_NS_1MS);
+	/* always wait for at least 1 ms */
+	Genode::uint64_t const v = wait_ns / RT_NS_1MS ? : 1;
+
+	RTSemEventMultiWait(_halt_semevent, v);
 	RTSemEventMultiReset(_halt_semevent);
 }