OS-XXXX bhyve should not hold HMA registration with no running VMscr5979-OS-XXXX

1 files changed, 53 insertions, 12 deletions

diff --git a/usr/src/uts/i86pc/io/vmm/vmm_sol_dev.c b/usr/src/uts/i86pc/io/vmm/vmm_sol_dev.c
index 4b759b44e9..2249774988 100644
--- a/usr/src/uts/i86pc/io/vmm/vmm_sol_dev.c
+++ b/usr/src/uts/i86pc/io/vmm/vmm_sol_dev.c
@@ -12,6 +12,7 @@
 /*
  * Copyright 2015 Pluribus Networks Inc.
  * Copyright 2019 Joyent, Inc.
+ * Copyright 2019 OmniOS Community Edition (OmniOSce) Association.
  */
 
 #include <sys/types.h>
@@ -1205,17 +1206,28 @@ vmmdev_do_vm_create(char *name, cred_t *cr)
 	vmm_softc_t	*sc = NULL;
 	minor_t		minor;
 	int		error = ENOMEM;
+	hma_reg_t	*reg = NULL;
 
 	if (strnlen(name, VM_MAX_NAMELEN) >= VM_MAX_NAMELEN) {
 		return (EINVAL);
 	}
 
+	mutex_enter(&vmmdev_mtx);
 	mutex_enter(&vmm_mtx);
 
+	if (vmmdev_hma_reg == NULL) {
+		if ((reg = hma_register(vmmdev_hvm_name)) == NULL) {
+			cmn_err(CE_WARN, "%s HMA registration failed.",
+			    vmmdev_hvm_name);
+			error = ENXIO;
+			goto exit;
+		}
+	}
+
 	/* Look for duplicates names */
 	if (vmm_lookup(name) != NULL) {
-		mutex_exit(&vmm_mtx);
-		return (EEXIST);
+		error = EEXIST;
+		goto exit;
 	}
 
 	/* Allow only one instance per non-global zone. */
@@ -1223,8 +1235,8 @@ vmmdev_do_vm_create(char *name, cred_t *cr)
 		for (sc = list_head(&vmm_list); sc != NULL;
 		    sc = list_next(&vmm_list, sc)) {
 			if (sc->vmm_zone == curzone) {
-				mutex_exit(&vmm_mtx);
-				return (EINVAL);
+				error = EINVAL;
+				goto exit;
 			}
 		}
 	}
@@ -1256,7 +1268,12 @@ vmmdev_do_vm_create(char *name, cred_t *cr)
 		vmm_zsd_add_vm(sc);
 
 		list_insert_tail(&vmm_list, sc);
+		if (reg != NULL) {
+			VERIFY(vmmdev_hma_reg == NULL);
+			vmmdev_hma_reg = reg;
+		}
 		mutex_exit(&vmm_mtx);
+		mutex_exit(&vmmdev_mtx);
 		return (0);
 	}
 
@@ -1266,7 +1283,13 @@ fail:
 	if (sc != NULL) {
 		ddi_soft_state_free(vmm_statep, minor);
 	}
+exit:
+	if (reg != NULL) {
+		hma_unregister(reg);
+	}
+
 	mutex_exit(&vmm_mtx);
+	mutex_exit(&vmmdev_mtx);
 
 	return (error);
 }
@@ -1487,6 +1510,7 @@ vmm_do_vm_destroy_locked(vmm_softc_t *sc, boolean_t clean_zsd)
 	dev_info_t	*pdip = ddi_get_parent(vmmdev_dip);
 	minor_t		minor;
 
+	ASSERT(MUTEX_HELD(&vmmdev_mtx));
 	ASSERT(MUTEX_HELD(&vmm_mtx));
 
 	if (clean_zsd) {
@@ -1514,6 +1538,11 @@ vmm_do_vm_destroy_locked(vmm_softc_t *sc, boolean_t clean_zsd)
 	}
 	(void) devfs_clean(pdip, NULL, DV_CLEAN_FORCE);
 
+	if (list_is_empty(&vmm_list)) {
+		hma_unregister(vmmdev_hma_reg);
+		vmmdev_hma_reg = NULL;
+	}
+
 	return (0);
 }
 
@@ -1522,9 +1551,11 @@ vmm_do_vm_destroy(vmm_softc_t *sc, boolean_t clean_zsd)
 {
 	int		err;
 
+	mutex_enter(&vmmdev_mtx);
 	mutex_enter(&vmm_mtx);
 	err = vmm_do_vm_destroy_locked(sc, clean_zsd);
 	mutex_exit(&vmm_mtx);
+	mutex_exit(&vmmdev_mtx);
 
 	return (err);
 }
@@ -1539,27 +1570,30 @@ vmmdev_do_vm_destroy(const char *name, cred_t *cr)
 	if (crgetuid(cr) != 0)
 		return (EPERM);
 
+	mutex_enter(&vmmdev_mtx);
 	mutex_enter(&vmm_mtx);
 
 	if ((sc = vmm_lookup(name)) == NULL) {
-		mutex_exit(&vmm_mtx);
-		return (ENOENT);
+		err = ENOENT;
+		goto exit;
 	}
 	/*
 	 * We don't check this in vmm_lookup() since that function is also used
 	 * for validation during create and currently vmm names must be unique.
 	 */
 	if (!INGLOBALZONE(curproc) && sc->vmm_zone != curzone) {
-		mutex_exit(&vmm_mtx);
-		return (EPERM);
+		err = EPERM;
+		goto exit;
 	}
 	err = vmm_do_vm_destroy_locked(sc, B_TRUE);
+
+exit:
 	mutex_exit(&vmm_mtx);
+	mutex_exit(&vmmdev_mtx);
 
 	return (err);
 }
 
-
 static int
 vmm_open(dev_t *devp, int flag, int otyp, cred_t *credp)
 {
@@ -1875,12 +1909,18 @@ vmm_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
 	vmm_sol_glue_init();
 	vmm_arena_init();
 
+	/*
+	 * Perform temporary HMA registration to determine if the hardware
+	 * is capable.
+	 */
 	if ((reg = hma_register(vmmdev_hvm_name)) == NULL) {
 		goto fail;
 	} else if (vmm_mod_load() != 0) {
 		goto fail;
 	}
 	vmm_loaded = B_TRUE;
+	hma_unregister(reg);
+	reg = NULL;
 
 	/* Create control node.  Other nodes will be created on demand. */
 	if (ddi_create_minor_node(dip, "ctl", S_IFCHR,
@@ -1894,7 +1934,6 @@ vmm_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
 	}
 
 	ddi_report_dev(dip);
-	vmmdev_hma_reg = reg;
 	vmmdev_sdev_hdl = sph;
 	vmmdev_dip = dip;
 	mutex_exit(&vmmdev_mtx);
@@ -1951,8 +1990,10 @@ vmm_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
 	vmmdev_dip = NULL;
 
 	VERIFY0(vmm_mod_unload());
-	hma_unregister(vmmdev_hma_reg);
-	vmmdev_hma_reg = NULL;
+	if (vmmdev_hma_reg != NULL) {
+		hma_unregister(vmmdev_hma_reg);
+		vmmdev_hma_reg = NULL;
+	}
 	vmm_arena_fini();
 	vmm_sol_glue_cleanup();