diff --git a/trusty/keymaster/keymaster_ipc.h b/trusty/keymaster/keymaster_ipc.h
index b38eb0592..d63757b36 100644
--- a/trusty/keymaster/keymaster_ipc.h
+++ b/trusty/keymaster/keymaster_ipc.h
@@ -24,7 +24,8 @@
 // Commands
 enum keymaster_command : uint32_t {
     KEYMASTER_RESP_BIT              = 1,
-    KEYMASTER_REQ_SHIFT             = 1,
+    KEYMASTER_STOP_BIT              = 2,
+    KEYMASTER_REQ_SHIFT             = 2,
 
     KM_GENERATE_KEY                 = (0 << KEYMASTER_REQ_SHIFT),
     KM_BEGIN_OPERATION              = (1 << KEYMASTER_REQ_SHIFT),
diff --git a/trusty/keymaster/trusty_keymaster_device.cpp b/trusty/keymaster/trusty_keymaster_device.cpp
index cfe94cc6c..ff741462e 100644
--- a/trusty/keymaster/trusty_keymaster_device.cpp
+++ b/trusty/keymaster/trusty_keymaster_device.cpp
@@ -36,7 +36,8 @@
 #include "trusty_keymaster_device.h"
 #include "trusty_keymaster_ipc.h"
 
-const uint32_t RECV_BUF_SIZE = PAGE_SIZE;
+// Maximum size of message from Trusty is 8K (for RSA attestation key and chain)
+const uint32_t RECV_BUF_SIZE = 2*PAGE_SIZE;
 const uint32_t SEND_BUF_SIZE = (PAGE_SIZE - sizeof(struct keymaster_message) - 16 /* tipc header */);
 
 const size_t kMaximumAttestationChallengeLength = 128;
@@ -770,6 +771,9 @@ keymaster_error_t TrustyKeymasterDevice::Send(uint32_t command, const Serializab
     ALOGV("Sending %d byte request\n", (int)req.SerializedSize());
     int rc = trusty_keymaster_call(command, send_buf, req_size, recv_buf, &rsp_size);
     if (rc < 0) {
+        // Reset the connection on tipc error
+        trusty_keymaster_disconnect();
+        trusty_keymaster_connect();
         ALOGE("tipc error: %d\n", rc);
         // TODO(swillden): Distinguish permanent from transient errors and set error_ appropriately.
         return translate_error(rc);
@@ -777,8 +781,7 @@ keymaster_error_t TrustyKeymasterDevice::Send(uint32_t command, const Serializab
         ALOGV("Received %d byte response\n", rsp_size);
     }
 
-    const keymaster_message* msg = (keymaster_message*)recv_buf;
-    const uint8_t* p = msg->payload;
+    const uint8_t* p = recv_buf;
     if (!rsp->Deserialize(&p, p + rsp_size)) {
         ALOGE("Error deserializing response of size %d\n", (int)rsp_size);
         return KM_ERROR_UNKNOWN_ERROR;
diff --git a/trusty/keymaster/trusty_keymaster_ipc.cpp b/trusty/keymaster/trusty_keymaster_ipc.cpp
index cdc27782a..54b251e93 100644
--- a/trusty/keymaster/trusty_keymaster_ipc.cpp
+++ b/trusty/keymaster/trusty_keymaster_ipc.cpp
@@ -23,6 +23,8 @@
 #include <string.h>
 #include <unistd.h>
 
+#include <algorithm>
+
 #include <log/log.h>
 #include <trusty/tipc.h>
 
@@ -31,7 +33,7 @@
 
 #define TRUSTY_DEVICE_NAME "/dev/trusty-ipc-dev0"
 
-static int handle_ = 0;
+static int handle_ = -1;
 
 int trusty_keymaster_connect() {
     int rc = tipc_connect(TRUSTY_DEVICE_NAME, KEYMASTER_PORT);
@@ -45,7 +47,7 @@ int trusty_keymaster_connect() {
 
 int trusty_keymaster_call(uint32_t cmd, void* in, uint32_t in_size, uint8_t* out,
                           uint32_t* out_size) {
-    if (handle_ == 0) {
+    if (handle_ < 0) {
         ALOGE("not connected\n");
         return -EINVAL;
     }
@@ -62,32 +64,43 @@ int trusty_keymaster_call(uint32_t cmd, void* in, uint32_t in_size, uint8_t* out
         ALOGE("failed to send cmd (%d) to %s: %s\n", cmd, KEYMASTER_PORT, strerror(errno));
         return -errno;
     }
+    size_t out_max_size = *out_size;
+    *out_size = 0;
+    struct iovec iov[2];
+    struct keymaster_message header;
+    iov[0] = {.iov_base = &header, .iov_len = sizeof(struct keymaster_message)};
+    while (true) {
+        iov[1] = {
+            .iov_base = out + *out_size,
+            .iov_len = std::min<uint32_t>(KEYMASTER_MAX_BUFFER_LENGTH, out_max_size - *out_size)};
+        rc = readv(handle_, iov, 2);
+        if (rc < 0) {
+            ALOGE("failed to retrieve response for cmd (%d) to %s: %s\n", cmd, KEYMASTER_PORT,
+                  strerror(errno));
+            return -errno;
+        }
 
-    rc = read(handle_, out, *out_size);
-    if (rc < 0) {
-        ALOGE("failed to retrieve response for cmd (%d) to %s: %s\n", cmd, KEYMASTER_PORT,
-              strerror(errno));
-        return -errno;
+        if ((size_t)rc < sizeof(struct keymaster_message)) {
+            ALOGE("invalid response size (%d)\n", (int)rc);
+            return -EINVAL;
+        }
+
+        if ((cmd | KEYMASTER_RESP_BIT) != (header.cmd & ~(KEYMASTER_STOP_BIT))) {
+            ALOGE("invalid command (%d)", header.cmd);
+            return -EINVAL;
+        }
+        *out_size += ((size_t)rc - sizeof(struct keymaster_message));
+        if (header.cmd & KEYMASTER_STOP_BIT) {
+            break;
+        }
     }
 
-    if ((size_t)rc < sizeof(struct keymaster_message)) {
-        ALOGE("invalid response size (%d)\n", (int)rc);
-        return -EINVAL;
-    }
-
-    msg = (struct keymaster_message*)out;
-
-    if ((cmd | KEYMASTER_RESP_BIT) != msg->cmd) {
-        ALOGE("invalid command (%d)", msg->cmd);
-        return -EINVAL;
-    }
-
-    *out_size = ((size_t)rc) - sizeof(struct keymaster_message);
     return rc;
 }
 
 void trusty_keymaster_disconnect() {
-    if (handle_ != 0) {
+    if (handle_ >= 0) {
         tipc_close(handle_);
     }
+    handle_ = -1;
 }