diff --git a/fastboot/fastboot.bash b/fastboot/fastboot.bash
index e9bf9e9..911071a 100644
--- a/fastboot/fastboot.bash
+++ b/fastboot/fastboot.bash
@@ -109,7 +109,7 @@
 
     cur="${COMP_WORDS[COMP_CWORD]}"
     if [[ $i -eq $COMP_CWORD ]]; then
-        partitions="boot bootloader dtbo init_boot modem odm odm_dlkm oem product pvmfw radio recovery system system_dlkm vbmeta vendor vendor_dlkm"
+        partitions="boot bootloader dtbo init_boot modem odm odm_dlkm oem product pvmfw radio recovery system system_dlkm vbmeta vendor vendor_dlkm vendor_kernel_boot"
         COMPREPLY=( $(compgen -W "$partitions" -- $cur) )
     else
         _fastboot_util_complete_local_file "${cur}" '!*.img'
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 39d86f9..79c3ac7 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -186,6 +186,11 @@
                   "vendor_dlkm.img",  "vendor_dlkm.sig",
                                                       "vendor_dlkm",
                                                                   true,  ImageType::Normal },
+    { "vendor_kernel_boot",
+                  "vendor_kernel_boot.img",
+                                      "vendor_kernel_boot.sig",
+                                                      "vendor_kernel_boot",
+                                                                  true,  ImageType::BootCritical },
     { nullptr,    "vendor_other.img", "vendor.sig",   "vendor",   true,  ImageType::Normal },
         // clang-format on
 };
diff --git a/rootdir/init.rc b/rootdir/init.rc
index cd71aa8..870a97b 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -823,7 +823,6 @@
     mkdir /data/misc/odsign 0710 root system
     # directory used for odsign metrics
     mkdir /data/misc/odsign/metrics 0770 root system
-
     # Directory for VirtualizationService temporary image files.
     # Delete any stale files owned by the old virtualizationservice uid (b/230056726).
     chmod 0770 /data/misc/virtualizationservice
@@ -1030,8 +1029,7 @@
     exec_start update_verifier_nonencrypted
     start statsd
     start netd
-    start zygote
-    start zygote_secondary
+    trigger zygote-run
 
 on zygote-start && property:ro.crypto.state=unsupported
     wait_for_prop odsign.verification.done 1
@@ -1039,8 +1037,7 @@
     exec_start update_verifier_nonencrypted
     start statsd
     start netd
-    start zygote
-    start zygote_secondary
+    trigger zygote-run
 
 on zygote-start && property:ro.crypto.state=encrypted && property:ro.crypto.type=file
     wait_for_prop odsign.verification.done 1
@@ -1048,6 +1045,15 @@
     exec_start update_verifier_nonencrypted
     start statsd
     start netd
+    trigger zygote-run
+
+on zygote-run && property:ro.zygote=zygote32
+    start zygote
+
+on zygote-run && property:ro.zygote=zygote64
+    start zygote
+
+on zygote-run && property:ro.zygote=zygote64_32
     start zygote
     start zygote_secondary
 
diff --git a/rootdir/init.zygote64_32.rc b/rootdir/init.zygote64_32.rc
index efb30d6..dfe1645 100644
--- a/rootdir/init.zygote64_32.rc
+++ b/rootdir/init.zygote64_32.rc
@@ -25,3 +25,4 @@
     socket usap_pool_secondary stream 660 root system
     onrestart restart zygote
     task_profiles ProcessCapacityHigh MaxPerformance
+    disabled
diff --git a/trusty/storage/interface/include/trusty/interface/storage.h b/trusty/storage/interface/include/trusty/interface/storage.h
index 3f1dcb8..255ade1 100644
--- a/trusty/storage/interface/include/trusty/interface/storage.h
+++ b/trusty/storage/interface/include/trusty/interface/storage.h
@@ -70,6 +70,9 @@
  * @STORAGE_ERR_TRANSACT        returned by various operations to indicate that current transaction
  *                              is in error state. Such state could be only cleared by sending
  *                              STORAGE_END_TRANSACTION message.
+ * @STORAGE_ERR_SYNC_FAILURE    indicates that the current operation failed to sync
+ *                              to disk. Only returned if STORAGE_MSG_FLAG_PRE_COMMIT or
+ *                              STORAGE_MSG_FLAG_POST_COMMIT was set for the request.
  */
 enum storage_err {
 	STORAGE_NO_ERROR          = 0,
@@ -80,6 +83,7 @@
 	STORAGE_ERR_NOT_FOUND     = 5,
 	STORAGE_ERR_EXIST         = 6,
 	STORAGE_ERR_TRANSACT      = 7,
+	STORAGE_ERR_SYNC_FAILURE  = 8,
 };
 
 /**
diff --git a/trusty/storage/proxy/proxy.c b/trusty/storage/proxy/proxy.c
index 2620034..f015892 100644
--- a/trusty/storage/proxy/proxy.c
+++ b/trusty/storage/proxy/proxy.c
@@ -116,10 +116,11 @@
 static int handle_req(struct storage_msg* msg, const void* req, size_t req_len) {
     int rc;
 
-    if ((msg->flags & STORAGE_MSG_FLAG_POST_COMMIT) && (msg->cmd != STORAGE_RPMB_SEND)) {
+    if ((msg->flags & STORAGE_MSG_FLAG_POST_COMMIT) && msg->cmd != STORAGE_RPMB_SEND &&
+        msg->cmd != STORAGE_FILE_WRITE) {
         /*
-         * handling post commit messages on non rpmb commands are not
-         * implemented as there is no use case for this yet.
+         * handling post commit messages on commands other than rpmb and write
+         * operations are not implemented as there is no use case for this yet.
          */
         ALOGE("cmd 0x%x: post commit option is not implemented\n", msg->cmd);
         msg->result = STORAGE_ERR_UNIMPLEMENTED;
@@ -129,7 +130,7 @@
     if (msg->flags & STORAGE_MSG_FLAG_PRE_COMMIT) {
         rc = storage_sync_checkpoint();
         if (rc < 0) {
-            msg->result = STORAGE_ERR_GENERIC;
+            msg->result = STORAGE_ERR_SYNC_FAILURE;
             return ipc_respond(msg, NULL, 0);
         }
     }
diff --git a/trusty/storage/proxy/storage.c b/trusty/storage/proxy/storage.c
index c00c399..c531cfd 100644
--- a/trusty/storage/proxy/storage.c
+++ b/trusty/storage/proxy/storage.c
@@ -407,6 +407,14 @@
         goto err_response;
     }
 
+    if (msg->flags & STORAGE_MSG_FLAG_POST_COMMIT) {
+        rc = storage_sync_checkpoint();
+        if (rc < 0) {
+            msg->result = STORAGE_ERR_SYNC_FAILURE;
+            goto err_response;
+        }
+    }
+
     msg->result = STORAGE_NO_ERROR;
 
 err_response: