diff --git a/src/system/kernel/fs/unused_vnodes.h b/src/system/kernel/fs/unused_vnodes.h
index e15860700b..10d2c8c005 100644
--- a/src/system/kernel/fs/unused_vnodes.h
+++ b/src/system/kernel/fs/unused_vnodes.h
@@ -26,9 +26,9 @@ const static uint32 kMaxUnusedVnodes = 8192;
 
 /*!	\brief Guards sUnusedVnodeList and sUnusedVnodes.
 
-	Innermost lock. Must not be held when acquiring any other lock.
+	Must have at least a read-lock of sHotVnodesLock when acquiring!
 */
-static mutex sUnusedVnodesLock = MUTEX_INITIALIZER("unused vnodes");
+static spinlock sUnusedVnodesLock = B_SPINLOCK_INITIALIZER;
 typedef DoublyLinkedList<Vnode, DoublyLinkedListMemberGetLink<Vnode, &Vnode::unused_link> >
 	UnusedVnodeList;
 static UnusedVnodeList sUnusedVnodeList;
@@ -48,7 +48,10 @@ static int32 sUnusedVnodesCheckCount = 0;
 static void
 flush_hot_vnodes_locked()
 {
-	MutexLocker unusedLocker(sUnusedVnodesLock);
+	// Since sUnusedVnodesLock is always acquired after sHotVnodesLock,
+	// we can safely hold it for the whole duration of the flush.
+	// We don't want to be descheduled while holding the write-lock, anyway.
+	InterruptsSpinLocker unusedLocker(sUnusedVnodesLock);
 
 	int32 count = std::min(sNextHotVnodeIndex, kMaxHotVnodes);
 	for (int32 i = 0; i < count; i++) {
@@ -147,7 +150,7 @@ vnode_used(Vnode* vnode)
 	vnode->SetUnused(false);
 
 	if (!vnode->IsHot()) {
-		MutexLocker unusedLocker(sUnusedVnodesLock);
+		InterruptsSpinLocker unusedLocker(sUnusedVnodesLock);
 		sUnusedVnodeList.Remove(vnode);
 		sUnusedVnodes--;
 	}
@@ -175,7 +178,7 @@ vnode_to_be_freed(Vnode* vnode)
 			}
 		}
 	} else if (vnode->IsUnused()) {
-		MutexLocker unusedLocker(sUnusedVnodesLock);
+		InterruptsSpinLocker unusedLocker(sUnusedVnodesLock);
 		sUnusedVnodeList.Remove(vnode);
 		sUnusedVnodes--;
 	}
diff --git a/src/system/kernel/fs/vfs.cpp b/src/system/kernel/fs/vfs.cpp
index 55719b8aa5..f29f795d04 100644
--- a/src/system/kernel/fs/vfs.cpp
+++ b/src/system/kernel/fs/vfs.cpp
@@ -1294,7 +1294,8 @@ free_unused_vnodes(int32 level)
 	// determine how many nodes to free
 	uint32 count = 1;
 	{
-		MutexLocker unusedVnodesLocker(sUnusedVnodesLock);
+		ReadLocker hotVnodesReadLocker(sHotVnodesLock);
+		InterruptsSpinLocker unusedVnodesLocker(sUnusedVnodesLock);
 
 		switch (level) {
 			case B_LOW_RESOURCE_NOTE:
@@ -1316,9 +1317,10 @@ free_unused_vnodes(int32 level)
 
 	for (uint32 i = 0; i < count; i++) {
 		ReadLocker vnodesReadLocker(sVnodeLock);
+		ReadLocker hotVnodesReadLocker(sHotVnodesLock);
 
 		// get the first node
-		MutexLocker unusedVnodesLocker(sUnusedVnodesLock);
+		InterruptsSpinLocker unusedVnodesLocker(sUnusedVnodesLock);
 		struct vnode* vnode = sUnusedVnodeList.First();
 		unusedVnodesLocker.Unlock();
 
@@ -1347,6 +1349,7 @@ free_unused_vnodes(int32 level)
 
 		// write back changes and free the node
 		nodeLocker.Unlock();
+		hotVnodesReadLocker.Unlock();
 		vnodesReadLocker.Unlock();
 
 		if (vnode->cache != NULL)