Merge "debuggerd: use One True timestamp function."
diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index 31c2d5d..ad10a1f 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -253,7 +253,6 @@
         "libcutils",
         "libdebuggerd_client",
         "liblog",
-        "libminijail",
         "libnativehelper",
         "libunwindstack",
     ],
@@ -261,6 +260,7 @@
     static_libs: [
         "libdebuggerd",
         "libgmock",
+        "libminijail",
     ],
 
     header_libs: [
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index 9d7658e..108787e 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -18,6 +18,7 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include <sys/capability.h>
+#include <sys/mman.h>
 #include <sys/prctl.h>
 #include <sys/ptrace.h>
 #include <sys/resource.h>
@@ -172,6 +173,8 @@
   void StartCrasher(const std::string& crash_type);
   void FinishCrasher();
   void AssertDeath(int signo);
+
+  static void Trap(void* ptr);
 };
 
 CrasherTest::CrasherTest() {
@@ -334,6 +337,48 @@
       R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr (0x100000000000dead|0xdead))");
 }
 
+// Marked as weak to prevent the compiler from removing the malloc in the caller. In theory, the
+// compiler could still clobber the argument register before trapping, but that's unlikely.
+__attribute__((weak)) void CrasherTest::Trap(void* ptr ATTRIBUTE_UNUSED) {
+  __builtin_trap();
+}
+
+TEST_F(CrasherTest, heap_addr_in_register) {
+#if defined(__i386__)
+  GTEST_SKIP() << "architecture does not pass arguments in registers";
+#endif
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([]() {
+    // Crash with a heap pointer in the first argument register.
+    Trap(malloc(1));
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  int status;
+  ASSERT_EQ(crasher_pid, TIMEOUT(30, waitpid(crasher_pid, &status, 0)));
+  ASSERT_TRUE(WIFSIGNALED(status)) << "crasher didn't terminate via a signal";
+  // Don't test the signal number because different architectures use different signals for
+  // __builtin_trap().
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+#if defined(__aarch64__)
+  ASSERT_MATCH(result, "memory near x0");
+#elif defined(__arm__)
+  ASSERT_MATCH(result, "memory near r0");
+#elif defined(__x86_64__)
+  ASSERT_MATCH(result, "memory near rdi");
+#else
+  ASSERT_TRUE(false) << "unsupported architecture";
+#endif
+}
+
 #if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
 static void SetTagCheckingLevelSync() {
   int tagged_addr_ctrl = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0);
@@ -512,6 +557,55 @@
 #endif
 }
 
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+static uintptr_t CreateTagMapping() {
+  uintptr_t mapping =
+      reinterpret_cast<uintptr_t>(mmap(nullptr, getpagesize(), PROT_READ | PROT_WRITE | PROT_MTE,
+                                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0));
+  if (reinterpret_cast<void*>(mapping) == MAP_FAILED) {
+    return 0;
+  }
+  __asm__ __volatile__(".arch_extension mte; stg %0, [%0]"
+                       :
+                       : "r"(mapping + (1ULL << 56))
+                       : "memory");
+  return mapping;
+}
+#endif
+
+TEST_F(CrasherTest, mte_tag_dump) {
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+  if (!mte_supported()) {
+    GTEST_SKIP() << "Requires MTE";
+  }
+
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([&]() {
+    SetTagCheckingLevelSync();
+    Trap(reinterpret_cast<void *>(CreateTagMapping()));
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  AssertDeath(SIGTRAP);
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+  ASSERT_MATCH(result, R"(memory near x0:
+.*
+.*
+    01.............0 0000000000000000 0000000000000000  ................
+    00.............0)");
+#else
+  GTEST_SKIP() << "Requires aarch64 + ANDROID_EXPERIMENTAL_MTE";
+#endif
+}
+
 TEST_F(CrasherTest, LD_PRELOAD) {
   int intercept_result;
   unique_fd output_fd;
diff --git a/debuggerd/libdebuggerd/test/dump_memory_test.cpp b/debuggerd/libdebuggerd/test/dump_memory_test.cpp
index be39582..f16f578 100644
--- a/debuggerd/libdebuggerd/test/dump_memory_test.cpp
+++ b/debuggerd/libdebuggerd/test/dump_memory_test.cpp
@@ -30,39 +30,39 @@
 const char g_expected_full_dump[] =
 "\nmemory near r1:\n"
 #if defined(__LP64__)
-"    0000000012345658 0706050403020100 0f0e0d0c0b0a0908  ................\n"
-"    0000000012345668 1716151413121110 1f1e1d1c1b1a1918  ................\n"
-"    0000000012345678 2726252423222120 2f2e2d2c2b2a2928   !\"#$%&'()*+,-./\n"
-"    0000000012345688 3736353433323130 3f3e3d3c3b3a3938  0123456789:;<=>?\n"
-"    0000000012345698 4746454443424140 4f4e4d4c4b4a4948  @ABCDEFGHIJKLMNO\n"
-"    00000000123456a8 5756555453525150 5f5e5d5c5b5a5958  PQRSTUVWXYZ[\\]^_\n"
-"    00000000123456b8 6766656463626160 6f6e6d6c6b6a6968  `abcdefghijklmno\n"
-"    00000000123456c8 7776757473727170 7f7e7d7c7b7a7978  pqrstuvwxyz{|}~.\n"
-"    00000000123456d8 8786858483828180 8f8e8d8c8b8a8988  ................\n"
-"    00000000123456e8 9796959493929190 9f9e9d9c9b9a9998  ................\n"
-"    00000000123456f8 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................\n"
-"    0000000012345708 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................\n"
-"    0000000012345718 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................\n"
-"    0000000012345728 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................\n"
-"    0000000012345738 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................\n"
-"    0000000012345748 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................\n";
+"    0000000012345650 0706050403020100 0f0e0d0c0b0a0908  ................\n"
+"    0000000012345660 1716151413121110 1f1e1d1c1b1a1918  ................\n"
+"    0000000012345670 2726252423222120 2f2e2d2c2b2a2928   !\"#$%&'()*+,-./\n"
+"    0000000012345680 3736353433323130 3f3e3d3c3b3a3938  0123456789:;<=>?\n"
+"    0000000012345690 4746454443424140 4f4e4d4c4b4a4948  @ABCDEFGHIJKLMNO\n"
+"    00000000123456a0 5756555453525150 5f5e5d5c5b5a5958  PQRSTUVWXYZ[\\]^_\n"
+"    00000000123456b0 6766656463626160 6f6e6d6c6b6a6968  `abcdefghijklmno\n"
+"    00000000123456c0 7776757473727170 7f7e7d7c7b7a7978  pqrstuvwxyz{|}~.\n"
+"    00000000123456d0 8786858483828180 8f8e8d8c8b8a8988  ................\n"
+"    00000000123456e0 9796959493929190 9f9e9d9c9b9a9998  ................\n"
+"    00000000123456f0 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................\n"
+"    0000000012345700 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................\n"
+"    0000000012345710 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................\n"
+"    0000000012345720 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................\n"
+"    0000000012345730 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................\n"
+"    0000000012345740 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................\n";
 #else
-"    12345658 03020100 07060504 0b0a0908 0f0e0d0c  ................\n"
-"    12345668 13121110 17161514 1b1a1918 1f1e1d1c  ................\n"
-"    12345678 23222120 27262524 2b2a2928 2f2e2d2c   !\"#$%&'()*+,-./\n"
-"    12345688 33323130 37363534 3b3a3938 3f3e3d3c  0123456789:;<=>?\n"
-"    12345698 43424140 47464544 4b4a4948 4f4e4d4c  @ABCDEFGHIJKLMNO\n"
-"    123456a8 53525150 57565554 5b5a5958 5f5e5d5c  PQRSTUVWXYZ[\\]^_\n"
-"    123456b8 63626160 67666564 6b6a6968 6f6e6d6c  `abcdefghijklmno\n"
-"    123456c8 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.\n"
-"    123456d8 83828180 87868584 8b8a8988 8f8e8d8c  ................\n"
-"    123456e8 93929190 97969594 9b9a9998 9f9e9d9c  ................\n"
-"    123456f8 a3a2a1a0 a7a6a5a4 abaaa9a8 afaeadac  ................\n"
-"    12345708 b3b2b1b0 b7b6b5b4 bbbab9b8 bfbebdbc  ................\n"
-"    12345718 c3c2c1c0 c7c6c5c4 cbcac9c8 cfcecdcc  ................\n"
-"    12345728 d3d2d1d0 d7d6d5d4 dbdad9d8 dfdedddc  ................\n"
-"    12345738 e3e2e1e0 e7e6e5e4 ebeae9e8 efeeedec  ................\n"
-"    12345748 f3f2f1f0 f7f6f5f4 fbfaf9f8 fffefdfc  ................\n";
+"    12345650 03020100 07060504 0b0a0908 0f0e0d0c  ................\n"
+"    12345660 13121110 17161514 1b1a1918 1f1e1d1c  ................\n"
+"    12345670 23222120 27262524 2b2a2928 2f2e2d2c   !\"#$%&'()*+,-./\n"
+"    12345680 33323130 37363534 3b3a3938 3f3e3d3c  0123456789:;<=>?\n"
+"    12345690 43424140 47464544 4b4a4948 4f4e4d4c  @ABCDEFGHIJKLMNO\n"
+"    123456a0 53525150 57565554 5b5a5958 5f5e5d5c  PQRSTUVWXYZ[\\]^_\n"
+"    123456b0 63626160 67666564 6b6a6968 6f6e6d6c  `abcdefghijklmno\n"
+"    123456c0 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.\n"
+"    123456d0 83828180 87868584 8b8a8988 8f8e8d8c  ................\n"
+"    123456e0 93929190 97969594 9b9a9998 9f9e9d9c  ................\n"
+"    123456f0 a3a2a1a0 a7a6a5a4 abaaa9a8 afaeadac  ................\n"
+"    12345700 b3b2b1b0 b7b6b5b4 bbbab9b8 bfbebdbc  ................\n"
+"    12345710 c3c2c1c0 c7c6c5c4 cbcac9c8 cfcecdcc  ................\n"
+"    12345720 d3d2d1d0 d7d6d5d4 dbdad9d8 dfdedddc  ................\n"
+"    12345730 e3e2e1e0 e7e6e5e4 ebeae9e8 efeeedec  ................\n"
+"    12345740 f3f2f1f0 f7f6f5f4 fbfaf9f8 fffefdfc  ................\n";
 #endif
 
 const char g_expected_partial_dump[] = \
@@ -112,7 +112,10 @@
     if (last_read_addr_ > 0) {
       offset = addr - last_read_addr_;
     }
-    size_t bytes_available = buffer_.size() - offset;
+    size_t bytes_available = 0;
+    if (offset < buffer_.size()) {
+      bytes_available = buffer_.size() - offset;
+    }
 
     if (partial_read_) {
       bytes = std::min(bytes, bytes_partial_read_);
@@ -258,44 +261,7 @@
   std::string tombstone_contents;
   ASSERT_TRUE(lseek(log_.tfd, 0, SEEK_SET) == 0);
   ASSERT_TRUE(android::base::ReadFdToString(log_.tfd, &tombstone_contents));
-  const char* expected_dump = \
-"\nmemory near pc:\n"
-#if defined(__LP64__)
-"    00000000a2345658 ---------------- ----------------  ................\n"
-"    00000000a2345668 ---------------- ----------------  ................\n"
-"    00000000a2345678 ---------------- ----------------  ................\n"
-"    00000000a2345688 ---------------- ----------------  ................\n"
-"    00000000a2345698 ---------------- ----------------  ................\n"
-"    00000000a23456a8 ---------------- ----------------  ................\n"
-"    00000000a23456b8 ---------------- ----------------  ................\n"
-"    00000000a23456c8 ---------------- ----------------  ................\n"
-"    00000000a23456d8 ---------------- ----------------  ................\n"
-"    00000000a23456e8 ---------------- ----------------  ................\n"
-"    00000000a23456f8 ---------------- ----------------  ................\n"
-"    00000000a2345708 ---------------- ----------------  ................\n"
-"    00000000a2345718 ---------------- ----------------  ................\n"
-"    00000000a2345728 ---------------- ----------------  ................\n"
-"    00000000a2345738 ---------------- ----------------  ................\n"
-"    00000000a2345748 ---------------- ----------------  ................\n";
-#else
-"    a2345658 -------- -------- -------- --------  ................\n"
-"    a2345668 -------- -------- -------- --------  ................\n"
-"    a2345678 -------- -------- -------- --------  ................\n"
-"    a2345688 -------- -------- -------- --------  ................\n"
-"    a2345698 -------- -------- -------- --------  ................\n"
-"    a23456a8 -------- -------- -------- --------  ................\n"
-"    a23456b8 -------- -------- -------- --------  ................\n"
-"    a23456c8 -------- -------- -------- --------  ................\n"
-"    a23456d8 -------- -------- -------- --------  ................\n"
-"    a23456e8 -------- -------- -------- --------  ................\n"
-"    a23456f8 -------- -------- -------- --------  ................\n"
-"    a2345708 -------- -------- -------- --------  ................\n"
-"    a2345718 -------- -------- -------- --------  ................\n"
-"    a2345728 -------- -------- -------- --------  ................\n"
-"    a2345738 -------- -------- -------- --------  ................\n"
-"    a2345748 -------- -------- -------- --------  ................\n";
-#endif
-  ASSERT_STREQ(expected_dump, tombstone_contents.c_str());
+  ASSERT_STREQ("", tombstone_contents.c_str());
 
   // Verify that the log buf is empty, and no error messages.
   ASSERT_STREQ("", getFakeLogBuf().c_str());
@@ -429,57 +395,17 @@
   ASSERT_STREQ("", getFakeLogPrint().c_str());
 }
 
-TEST_F(DumpMemoryTest, memory_address_too_low) {
-  uint8_t buffer[256];
-  memset(buffer, 0, sizeof(buffer));
-  memory_mock_->SetReadData(buffer, sizeof(buffer));
-
-  dump_memory(&log_, memory_mock_.get(), 0, "memory near r1");
-
-  std::string tombstone_contents;
-  ASSERT_TRUE(lseek(log_.tfd, 0, SEEK_SET) == 0);
-  ASSERT_TRUE(android::base::ReadFdToString(log_.tfd, &tombstone_contents));
-  ASSERT_STREQ("", tombstone_contents.c_str());
-
-  // Verify that the log buf is empty, and no error messages.
-  ASSERT_STREQ("", getFakeLogBuf().c_str());
-  ASSERT_STREQ("", getFakeLogPrint().c_str());
-}
-
 TEST_F(DumpMemoryTest, memory_address_too_high) {
   uint8_t buffer[256];
   memset(buffer, 0, sizeof(buffer));
   memory_mock_->SetReadData(buffer, sizeof(buffer));
 
 #if defined(__LP64__)
-  dump_memory(&log_, memory_mock_.get(), 0x4000000000000000UL, "memory near r1");
-  dump_memory(&log_, memory_mock_.get(), 0x4000000000000000UL - 32, "memory near r1");
-  dump_memory(&log_, memory_mock_.get(), 0x4000000000000000UL - 216, "memory near r1");
+  dump_memory(&log_, memory_mock_.get(), -32, "memory near r1");
+  dump_memory(&log_, memory_mock_.get(), -208, "memory near r1");
 #else
-  dump_memory(&log_, memory_mock_.get(), 0xffff0000, "memory near r1");
-  dump_memory(&log_, memory_mock_.get(), 0xffff0000 - 32, "memory near r1");
-  dump_memory(&log_, memory_mock_.get(), 0xffff0000 - 220, "memory near r1");
-#endif
-
-  std::string tombstone_contents;
-  ASSERT_TRUE(lseek(log_.tfd, 0, SEEK_SET) == 0);
-  ASSERT_TRUE(android::base::ReadFdToString(log_.tfd, &tombstone_contents));
-  ASSERT_STREQ("", tombstone_contents.c_str());
-
-  // Verify that the log buf is empty, and no error messages.
-  ASSERT_STREQ("", getFakeLogBuf().c_str());
-  ASSERT_STREQ("", getFakeLogPrint().c_str());
-}
-
-TEST_F(DumpMemoryTest, memory_address_would_overflow) {
-  uint8_t buffer[256];
-  memset(buffer, 0, sizeof(buffer));
-  memory_mock_->SetReadData(buffer, sizeof(buffer));
-
-#if defined(__LP64__)
-  dump_memory(&log_, memory_mock_.get(), 0xfffffffffffffff0, "memory near r1");
-#else
-  dump_memory(&log_, memory_mock_.get(), 0xfffffff0, "memory near r1");
+  dump_memory(&log_, memory_mock_.get(), 0x100000000 - 32, "memory near r1");
+  dump_memory(&log_, memory_mock_.get(), 0x100000000 - 208, "memory near r1");
 #endif
 
   std::string tombstone_contents;
@@ -500,9 +426,9 @@
   memory_mock_->SetReadData(buffer, sizeof(buffer));
 
 #if defined(__LP64__)
-  dump_memory(&log_, memory_mock_.get(), 0x4000000000000000UL - 224, "memory near r4");
+  dump_memory(&log_, memory_mock_.get(), -224, "memory near r4");
 #else
-  dump_memory(&log_, memory_mock_.get(), 0xffff0000 - 224, "memory near r4");
+  dump_memory(&log_, memory_mock_.get(), 0x100000000 - 224, "memory near r4");
 #endif
 
   std::string tombstone_contents;
@@ -510,40 +436,57 @@
   ASSERT_TRUE(android::base::ReadFdToString(log_.tfd, &tombstone_contents));
   const char* expected_dump = \
 "\nmemory near r4:\n"
-#if defined(__LP64__)
-"    3fffffffffffff00 0706050403020100 0f0e0d0c0b0a0908  ................\n"
-"    3fffffffffffff10 1716151413121110 1f1e1d1c1b1a1918  ................\n"
-"    3fffffffffffff20 2726252423222120 2f2e2d2c2b2a2928   !\"#$%&'()*+,-./\n"
-"    3fffffffffffff30 3736353433323130 3f3e3d3c3b3a3938  0123456789:;<=>?\n"
-"    3fffffffffffff40 4746454443424140 4f4e4d4c4b4a4948  @ABCDEFGHIJKLMNO\n"
-"    3fffffffffffff50 5756555453525150 5f5e5d5c5b5a5958  PQRSTUVWXYZ[\\]^_\n"
-"    3fffffffffffff60 6766656463626160 6f6e6d6c6b6a6968  `abcdefghijklmno\n"
-"    3fffffffffffff70 7776757473727170 7f7e7d7c7b7a7978  pqrstuvwxyz{|}~.\n"
-"    3fffffffffffff80 8786858483828180 8f8e8d8c8b8a8988  ................\n"
-"    3fffffffffffff90 9796959493929190 9f9e9d9c9b9a9998  ................\n"
-"    3fffffffffffffa0 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................\n"
-"    3fffffffffffffb0 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................\n"
-"    3fffffffffffffc0 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................\n"
-"    3fffffffffffffd0 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................\n"
-"    3fffffffffffffe0 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................\n"
-"    3ffffffffffffff0 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................\n";
+#if defined(__aarch64__)
+"    00ffffffffffff00 0706050403020100 0f0e0d0c0b0a0908  ................\n"
+"    00ffffffffffff10 1716151413121110 1f1e1d1c1b1a1918  ................\n"
+"    00ffffffffffff20 2726252423222120 2f2e2d2c2b2a2928   !\"#$%&'()*+,-./\n"
+"    00ffffffffffff30 3736353433323130 3f3e3d3c3b3a3938  0123456789:;<=>?\n"
+"    00ffffffffffff40 4746454443424140 4f4e4d4c4b4a4948  @ABCDEFGHIJKLMNO\n"
+"    00ffffffffffff50 5756555453525150 5f5e5d5c5b5a5958  PQRSTUVWXYZ[\\]^_\n"
+"    00ffffffffffff60 6766656463626160 6f6e6d6c6b6a6968  `abcdefghijklmno\n"
+"    00ffffffffffff70 7776757473727170 7f7e7d7c7b7a7978  pqrstuvwxyz{|}~.\n"
+"    00ffffffffffff80 8786858483828180 8f8e8d8c8b8a8988  ................\n"
+"    00ffffffffffff90 9796959493929190 9f9e9d9c9b9a9998  ................\n"
+"    00ffffffffffffa0 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................\n"
+"    00ffffffffffffb0 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................\n"
+"    00ffffffffffffc0 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................\n"
+"    00ffffffffffffd0 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................\n"
+"    00ffffffffffffe0 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................\n"
+"    00fffffffffffff0 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................\n";
+#elif defined(__LP64__)
+"    ffffffffffffff00 0706050403020100 0f0e0d0c0b0a0908  ................\n"
+"    ffffffffffffff10 1716151413121110 1f1e1d1c1b1a1918  ................\n"
+"    ffffffffffffff20 2726252423222120 2f2e2d2c2b2a2928   !\"#$%&'()*+,-./\n"
+"    ffffffffffffff30 3736353433323130 3f3e3d3c3b3a3938  0123456789:;<=>?\n"
+"    ffffffffffffff40 4746454443424140 4f4e4d4c4b4a4948  @ABCDEFGHIJKLMNO\n"
+"    ffffffffffffff50 5756555453525150 5f5e5d5c5b5a5958  PQRSTUVWXYZ[\\]^_\n"
+"    ffffffffffffff60 6766656463626160 6f6e6d6c6b6a6968  `abcdefghijklmno\n"
+"    ffffffffffffff70 7776757473727170 7f7e7d7c7b7a7978  pqrstuvwxyz{|}~.\n"
+"    ffffffffffffff80 8786858483828180 8f8e8d8c8b8a8988  ................\n"
+"    ffffffffffffff90 9796959493929190 9f9e9d9c9b9a9998  ................\n"
+"    ffffffffffffffa0 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................\n"
+"    ffffffffffffffb0 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................\n"
+"    ffffffffffffffc0 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................\n"
+"    ffffffffffffffd0 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................\n"
+"    ffffffffffffffe0 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................\n"
+"    fffffffffffffff0 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................\n";
 #else
-"    fffeff00 03020100 07060504 0b0a0908 0f0e0d0c  ................\n"
-"    fffeff10 13121110 17161514 1b1a1918 1f1e1d1c  ................\n"
-"    fffeff20 23222120 27262524 2b2a2928 2f2e2d2c   !\"#$%&'()*+,-./\n"
-"    fffeff30 33323130 37363534 3b3a3938 3f3e3d3c  0123456789:;<=>?\n"
-"    fffeff40 43424140 47464544 4b4a4948 4f4e4d4c  @ABCDEFGHIJKLMNO\n"
-"    fffeff50 53525150 57565554 5b5a5958 5f5e5d5c  PQRSTUVWXYZ[\\]^_\n"
-"    fffeff60 63626160 67666564 6b6a6968 6f6e6d6c  `abcdefghijklmno\n"
-"    fffeff70 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.\n"
-"    fffeff80 83828180 87868584 8b8a8988 8f8e8d8c  ................\n"
-"    fffeff90 93929190 97969594 9b9a9998 9f9e9d9c  ................\n"
-"    fffeffa0 a3a2a1a0 a7a6a5a4 abaaa9a8 afaeadac  ................\n"
-"    fffeffb0 b3b2b1b0 b7b6b5b4 bbbab9b8 bfbebdbc  ................\n"
-"    fffeffc0 c3c2c1c0 c7c6c5c4 cbcac9c8 cfcecdcc  ................\n"
-"    fffeffd0 d3d2d1d0 d7d6d5d4 dbdad9d8 dfdedddc  ................\n"
-"    fffeffe0 e3e2e1e0 e7e6e5e4 ebeae9e8 efeeedec  ................\n"
-"    fffefff0 f3f2f1f0 f7f6f5f4 fbfaf9f8 fffefdfc  ................\n";
+"    ffffff00 03020100 07060504 0b0a0908 0f0e0d0c  ................\n"
+"    ffffff10 13121110 17161514 1b1a1918 1f1e1d1c  ................\n"
+"    ffffff20 23222120 27262524 2b2a2928 2f2e2d2c   !\"#$%&'()*+,-./\n"
+"    ffffff30 33323130 37363534 3b3a3938 3f3e3d3c  0123456789:;<=>?\n"
+"    ffffff40 43424140 47464544 4b4a4948 4f4e4d4c  @ABCDEFGHIJKLMNO\n"
+"    ffffff50 53525150 57565554 5b5a5958 5f5e5d5c  PQRSTUVWXYZ[\\]^_\n"
+"    ffffff60 63626160 67666564 6b6a6968 6f6e6d6c  `abcdefghijklmno\n"
+"    ffffff70 73727170 77767574 7b7a7978 7f7e7d7c  pqrstuvwxyz{|}~.\n"
+"    ffffff80 83828180 87868584 8b8a8988 8f8e8d8c  ................\n"
+"    ffffff90 93929190 97969594 9b9a9998 9f9e9d9c  ................\n"
+"    ffffffa0 a3a2a1a0 a7a6a5a4 abaaa9a8 afaeadac  ................\n"
+"    ffffffb0 b3b2b1b0 b7b6b5b4 bbbab9b8 bfbebdbc  ................\n"
+"    ffffffc0 c3c2c1c0 c7c6c5c4 cbcac9c8 cfcecdcc  ................\n"
+"    ffffffd0 d3d2d1d0 d7d6d5d4 dbdad9d8 dfdedddc  ................\n"
+"    ffffffe0 e3e2e1e0 e7e6e5e4 ebeae9e8 efeeedec  ................\n"
+"    fffffff0 f3f2f1f0 f7f6f5f4 fbfaf9f8 fffefdfc  ................\n";
 #endif
   ASSERT_STREQ(expected_dump, tombstone_contents.c_str());
 
@@ -570,39 +513,41 @@
   const char* expected_dump = \
 "\nmemory near r4:\n"
 #if defined(__LP64__)
-"    0000000010000f88 ---------------- ----------------  ................\n"
-"    0000000010000f98 ---------------- ----------------  ................\n"
-"    0000000010000fa8 ---------------- ----------------  ................\n"
-"    0000000010000fb8 ---------------- ----------------  ................\n"
-"    0000000010000fc8 ---------------- ----------------  ................\n"
-"    0000000010000fd8 ---------------- ----------------  ................\n"
-"    0000000010000fe8 ---------------- ----------------  ................\n"
-"    0000000010000ff8 ---------------- 7f7e7d7c7b7a7978  ........xyz{|}~.\n"
-"    0000000010001008 8786858483828180 8f8e8d8c8b8a8988  ................\n"
-"    0000000010001018 9796959493929190 9f9e9d9c9b9a9998  ................\n"
-"    0000000010001028 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................\n"
-"    0000000010001038 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................\n"
-"    0000000010001048 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................\n"
-"    0000000010001058 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................\n"
-"    0000000010001068 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................\n"
-"    0000000010001078 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................\n";
+R"(    0000000010000f80 ---------------- ----------------  ................
+    0000000010000f90 ---------------- ----------------  ................
+    0000000010000fa0 ---------------- ----------------  ................
+    0000000010000fb0 ---------------- ----------------  ................
+    0000000010000fc0 ---------------- ----------------  ................
+    0000000010000fd0 ---------------- ----------------  ................
+    0000000010000fe0 ---------------- ----------------  ................
+    0000000010000ff0 ---------------- ----------------  ................
+    0000000010001000 8786858483828180 8f8e8d8c8b8a8988  ................
+    0000000010001010 9796959493929190 9f9e9d9c9b9a9998  ................
+    0000000010001020 a7a6a5a4a3a2a1a0 afaeadacabaaa9a8  ................
+    0000000010001030 b7b6b5b4b3b2b1b0 bfbebdbcbbbab9b8  ................
+    0000000010001040 c7c6c5c4c3c2c1c0 cfcecdcccbcac9c8  ................
+    0000000010001050 d7d6d5d4d3d2d1d0 dfdedddcdbdad9d8  ................
+    0000000010001060 e7e6e5e4e3e2e1e0 efeeedecebeae9e8  ................
+    0000000010001070 f7f6f5f4f3f2f1f0 fffefdfcfbfaf9f8  ................
+)";
 #else
-"    10000f88 -------- -------- -------- --------  ................\n"
-"    10000f98 -------- -------- -------- --------  ................\n"
-"    10000fa8 -------- -------- -------- --------  ................\n"
-"    10000fb8 -------- -------- -------- --------  ................\n"
-"    10000fc8 -------- -------- -------- --------  ................\n"
-"    10000fd8 -------- -------- -------- --------  ................\n"
-"    10000fe8 -------- -------- -------- --------  ................\n"
-"    10000ff8 -------- -------- 7b7a7978 7f7e7d7c  ........xyz{|}~.\n"
-"    10001008 83828180 87868584 8b8a8988 8f8e8d8c  ................\n"
-"    10001018 93929190 97969594 9b9a9998 9f9e9d9c  ................\n"
-"    10001028 a3a2a1a0 a7a6a5a4 abaaa9a8 afaeadac  ................\n"
-"    10001038 b3b2b1b0 b7b6b5b4 bbbab9b8 bfbebdbc  ................\n"
-"    10001048 c3c2c1c0 c7c6c5c4 cbcac9c8 cfcecdcc  ................\n"
-"    10001058 d3d2d1d0 d7d6d5d4 dbdad9d8 dfdedddc  ................\n"
-"    10001068 e3e2e1e0 e7e6e5e4 ebeae9e8 efeeedec  ................\n"
-"    10001078 f3f2f1f0 f7f6f5f4 fbfaf9f8 fffefdfc  ................\n";
+R"(    10000f80 -------- -------- -------- --------  ................
+    10000f90 -------- -------- -------- --------  ................
+    10000fa0 -------- -------- -------- --------  ................
+    10000fb0 -------- -------- -------- --------  ................
+    10000fc0 -------- -------- -------- --------  ................
+    10000fd0 -------- -------- -------- --------  ................
+    10000fe0 -------- -------- -------- --------  ................
+    10000ff0 -------- -------- -------- --------  ................
+    10001000 83828180 87868584 8b8a8988 8f8e8d8c  ................
+    10001010 93929190 97969594 9b9a9998 9f9e9d9c  ................
+    10001020 a3a2a1a0 a7a6a5a4 abaaa9a8 afaeadac  ................
+    10001030 b3b2b1b0 b7b6b5b4 bbbab9b8 bfbebdbc  ................
+    10001040 c3c2c1c0 c7c6c5c4 cbcac9c8 cfcecdcc  ................
+    10001050 d3d2d1d0 d7d6d5d4 dbdad9d8 dfdedddc  ................
+    10001060 e3e2e1e0 e7e6e5e4 ebeae9e8 efeeedec  ................
+    10001070 f3f2f1f0 f7f6f5f4 fbfaf9f8 fffefdfc  ................
+)";
 #endif
   ASSERT_STREQ(expected_dump, tombstone_contents.c_str());
 
@@ -684,44 +629,7 @@
   std::string tombstone_contents;
   ASSERT_TRUE(lseek(log_.tfd, 0, SEEK_SET) == 0);
   ASSERT_TRUE(android::base::ReadFdToString(log_.tfd, &tombstone_contents));
-  const char* expected_dump = \
-"\nmemory near r4:\n"
-#if defined(__LP64__)
-"    0000000010000000 ---------------- ----------------  ................\n"
-"    0000000010000010 ---------------- ----------------  ................\n"
-"    0000000010000020 ---------------- ----------------  ................\n"
-"    0000000010000030 ---------------- ----------------  ................\n"
-"    0000000010000040 ---------------- ----------------  ................\n"
-"    0000000010000050 ---------------- ----------------  ................\n"
-"    0000000010000060 ---------------- ----------------  ................\n"
-"    0000000010000070 ---------------- ----------------  ................\n"
-"    0000000010000080 ---------------- ----------------  ................\n"
-"    0000000010000090 ---------------- ----------------  ................\n"
-"    00000000100000a0 ---------------- ----------------  ................\n"
-"    00000000100000b0 ---------------- ----------------  ................\n"
-"    00000000100000c0 ---------------- ----------------  ................\n"
-"    00000000100000d0 ---------------- ----------------  ................\n"
-"    00000000100000e0 ---------------- ----------------  ................\n"
-"    00000000100000f0 ---------------- ----------------  ................\n";
-#else
-"    10000000 -------- -------- -------- --------  ................\n"
-"    10000010 -------- -------- -------- --------  ................\n"
-"    10000020 -------- -------- -------- --------  ................\n"
-"    10000030 -------- -------- -------- --------  ................\n"
-"    10000040 -------- -------- -------- --------  ................\n"
-"    10000050 -------- -------- -------- --------  ................\n"
-"    10000060 -------- -------- -------- --------  ................\n"
-"    10000070 -------- -------- -------- --------  ................\n"
-"    10000080 -------- -------- -------- --------  ................\n"
-"    10000090 -------- -------- -------- --------  ................\n"
-"    100000a0 -------- -------- -------- --------  ................\n"
-"    100000b0 -------- -------- -------- --------  ................\n"
-"    100000c0 -------- -------- -------- --------  ................\n"
-"    100000d0 -------- -------- -------- --------  ................\n"
-"    100000e0 -------- -------- -------- --------  ................\n"
-"    100000f0 -------- -------- -------- --------  ................\n";
-#endif
-  ASSERT_STREQ(expected_dump, tombstone_contents.c_str());
+  ASSERT_STREQ("", tombstone_contents.c_str());
 
   // Verify that the log buf is empty, and no error messages.
   ASSERT_STREQ("", getFakeLogBuf().c_str());
@@ -744,44 +652,7 @@
   std::string tombstone_contents;
   ASSERT_TRUE(lseek(log_.tfd, 0, SEEK_SET) == 0);
   ASSERT_TRUE(android::base::ReadFdToString(log_.tfd, &tombstone_contents));
-  const char* expected_dump = \
-"\nmemory near r4:\n"
-#if defined(__LP64__)
-"    0000000010000f00 ---------------- ----------------  ................\n"
-"    0000000010000f10 ---------------- ----------------  ................\n"
-"    0000000010000f20 ---------------- ----------------  ................\n"
-"    0000000010000f30 ---------------- ----------------  ................\n"
-"    0000000010000f40 ---------------- ----------------  ................\n"
-"    0000000010000f50 ---------------- ----------------  ................\n"
-"    0000000010000f60 ---------------- ----------------  ................\n"
-"    0000000010000f70 ---------------- ----------------  ................\n"
-"    0000000010000f80 ---------------- ----------------  ................\n"
-"    0000000010000f90 ---------------- ----------------  ................\n"
-"    0000000010000fa0 ---------------- ----------------  ................\n"
-"    0000000010000fb0 ---------------- ----------------  ................\n"
-"    0000000010000fc0 ---------------- ----------------  ................\n"
-"    0000000010000fd0 ---------------- ----------------  ................\n"
-"    0000000010000fe0 ---------------- ----------------  ................\n"
-"    0000000010000ff0 ---------------- ----------------  ................\n";
-#else
-"    10000f00 -------- -------- -------- --------  ................\n"
-"    10000f10 -------- -------- -------- --------  ................\n"
-"    10000f20 -------- -------- -------- --------  ................\n"
-"    10000f30 -------- -------- -------- --------  ................\n"
-"    10000f40 -------- -------- -------- --------  ................\n"
-"    10000f50 -------- -------- -------- --------  ................\n"
-"    10000f60 -------- -------- -------- --------  ................\n"
-"    10000f70 -------- -------- -------- --------  ................\n"
-"    10000f80 -------- -------- -------- --------  ................\n"
-"    10000f90 -------- -------- -------- --------  ................\n"
-"    10000fa0 -------- -------- -------- --------  ................\n"
-"    10000fb0 -------- -------- -------- --------  ................\n"
-"    10000fc0 -------- -------- -------- --------  ................\n"
-"    10000fd0 -------- -------- -------- --------  ................\n"
-"    10000fe0 -------- -------- -------- --------  ................\n"
-"    10000ff0 -------- -------- -------- --------  ................\n";
-#endif
-  ASSERT_STREQ(expected_dump, tombstone_contents.c_str());
+  ASSERT_STREQ("", tombstone_contents.c_str());
 
   // Verify that the log buf is empty, and no error messages.
   ASSERT_STREQ("", getFakeLogBuf().c_str());
diff --git a/debuggerd/libdebuggerd/utility.cpp b/debuggerd/libdebuggerd/utility.cpp
index 92d1da3..f43092c 100644
--- a/debuggerd/libdebuggerd/utility.cpp
+++ b/debuggerd/libdebuggerd/utility.cpp
@@ -129,24 +129,23 @@
 #define MEMORY_BYTES_PER_LINE 16
 
 void dump_memory(log_t* log, unwindstack::Memory* memory, uint64_t addr, const std::string& label) {
-  // Align the address to sizeof(long) and start 32 bytes before the address.
-  addr &= ~(sizeof(long) - 1);
+  // Align the address to the number of bytes per line to avoid confusing memory tag output if
+  // memory is tagged and we start from a misaligned address. Start 32 bytes before the address.
+  addr &= ~(MEMORY_BYTES_PER_LINE - 1);
   if (addr >= 4128) {
     addr -= 32;
   }
 
-  // Don't bother if the address looks too low, or looks too high.
-  if (addr < 4096 ||
-#if defined(__LP64__)
-      addr > 0x4000000000000000UL - MEMORY_BYTES_TO_DUMP) {
-#else
-      addr > 0xffff0000 - MEMORY_BYTES_TO_DUMP) {
-#endif
+  // We don't want the address tag to appear in the addresses in the memory dump.
+  addr = untag_address(addr);
+
+  // Don't bother if the address would overflow, taking tag bits into account. Note that
+  // untag_address truncates to 32 bits on 32-bit platforms as a side effect of returning a
+  // uintptr_t, so this also checks for 32-bit overflow.
+  if (untag_address(addr + MEMORY_BYTES_TO_DUMP - 1) < addr) {
     return;
   }
 
-  _LOG(log, logtype::MEMORY, "\n%s:\n", label.c_str());
-
   // Dump 256 bytes
   uintptr_t data[MEMORY_BYTES_TO_DUMP/sizeof(uintptr_t)];
   memset(data, 0, MEMORY_BYTES_TO_DUMP);
@@ -187,6 +186,15 @@
     }
   }
 
+  // If we were unable to read anything, it probably means that the register doesn't contain a
+  // valid pointer. In that case, skip the output for this register entirely rather than emitting 16
+  // lines of dashes.
+  if (bytes == 0) {
+    return;
+  }
+
+  _LOG(log, logtype::MEMORY, "\n%s:\n", label.c_str());
+
   // Dump the code around memory as:
   //  addr             contents                           ascii
   //  0000000000008d34 ef000000e8bd0090 e1b00000512fff1e  ............../Q
@@ -197,8 +205,13 @@
   size_t current = 0;
   size_t total_bytes = start + bytes;
   for (size_t line = 0; line < MEMORY_BYTES_TO_DUMP / MEMORY_BYTES_PER_LINE; line++) {
+    uint64_t tagged_addr = addr;
+    long tag = memory->ReadTag(addr);
+    if (tag >= 0) {
+      tagged_addr |= static_cast<uint64_t>(tag) << 56;
+    }
     std::string logline;
-    android::base::StringAppendF(&logline, "    %" PRIPTR, addr);
+    android::base::StringAppendF(&logline, "    %" PRIPTR, tagged_addr);
 
     addr += MEMORY_BYTES_PER_LINE;
     std::string ascii;
diff --git a/fastboot/fuzzy_fastboot/main.cpp b/fastboot/fuzzy_fastboot/main.cpp
index e7f785b..34ab32c 100644
--- a/fastboot/fuzzy_fastboot/main.cpp
+++ b/fastboot/fuzzy_fastboot/main.cpp
@@ -1286,7 +1286,7 @@
     ASSERT_TRUE(PartitionHash(fb.get(), "userdata", &hash_buf, &retcode, &err_msg)) << err_msg;
     ASSERT_EQ(retcode, 0) << err_msg;
 
-    // Sanity check of hash
+    // Validity check of hash
     EXPECT_NE(hash_before, hash_buf)
             << "Writing a random buffer to 'userdata' had the same hash as after erasing it";
     SetLockState(true);  // Lock the device
diff --git a/fs_mgr/libfiemap/fiemap_writer.cpp b/fs_mgr/libfiemap/fiemap_writer.cpp
index 4dd4bcc..621031a 100644
--- a/fs_mgr/libfiemap/fiemap_writer.cpp
+++ b/fs_mgr/libfiemap/fiemap_writer.cpp
@@ -45,7 +45,7 @@
 
 using namespace android::dm;
 
-// We cap the maximum number of extents as a sanity measure.
+// We cap the maximum number of extents as a robustness measure.
 static constexpr uint32_t kMaxExtents = 50000;
 
 // TODO: Fallback to using fibmap if FIEMAP_EXTENT_MERGED is set.
diff --git a/fs_mgr/libfiemap/split_fiemap_writer.cpp b/fs_mgr/libfiemap/split_fiemap_writer.cpp
index 12c7397..36bb3df 100644
--- a/fs_mgr/libfiemap/split_fiemap_writer.cpp
+++ b/fs_mgr/libfiemap/split_fiemap_writer.cpp
@@ -266,7 +266,7 @@
         cursor_file_pos_ += bytes_to_write;
     }
 
-    // If we've reached the end of the current file, close it for sanity.
+    // If we've reached the end of the current file, close it.
     if (cursor_file_pos_ == file->size()) {
         cursor_fd_ = {};
     }
diff --git a/fs_mgr/libfiemap/utility.cpp b/fs_mgr/libfiemap/utility.cpp
index bbb0510..c189855 100644
--- a/fs_mgr/libfiemap/utility.cpp
+++ b/fs_mgr/libfiemap/utility.cpp
@@ -139,8 +139,7 @@
     }
 
     *bdev_name = ::android::base::Basename(sysfs_bdev);
-    // Paranoid sanity check to make sure we just didn't get the
-    // input in return as-is.
+    // Check that the symlink doesn't point to itself.
     if (sysfs_bdev == *bdev_name) {
         LOG(ERROR) << "Malformed symlink for block device: " << sysfs_bdev;
         return false;
diff --git a/fs_mgr/libfs_avb/avb_ops.cpp b/fs_mgr/libfs_avb/avb_ops.cpp
index c192bf5..46072bb 100644
--- a/fs_mgr/libfs_avb/avb_ops.cpp
+++ b/fs_mgr/libfs_avb/avb_ops.cpp
@@ -52,16 +52,16 @@
             partition, offset, num_bytes, buffer, out_num_read);
 }
 
-static AvbIOResult dummy_read_rollback_index(AvbOps* ops ATTRIBUTE_UNUSED,
-                                             size_t rollback_index_location ATTRIBUTE_UNUSED,
-                                             uint64_t* out_rollback_index) {
+static AvbIOResult no_op_read_rollback_index(AvbOps* ops ATTRIBUTE_UNUSED,
+                                            size_t rollback_index_location ATTRIBUTE_UNUSED,
+                                            uint64_t* out_rollback_index) {
     // rollback_index has been checked in bootloader phase.
     // In user-space, returns the smallest value 0 to pass the check.
     *out_rollback_index = 0;
     return AVB_IO_RESULT_OK;
 }
 
-static AvbIOResult dummy_validate_vbmeta_public_key(
+static AvbIOResult no_op_validate_vbmeta_public_key(
         AvbOps* ops ATTRIBUTE_UNUSED, const uint8_t* public_key_data ATTRIBUTE_UNUSED,
         size_t public_key_length ATTRIBUTE_UNUSED,
         const uint8_t* public_key_metadata ATTRIBUTE_UNUSED,
@@ -76,8 +76,8 @@
     return AVB_IO_RESULT_OK;
 }
 
-static AvbIOResult dummy_read_is_device_unlocked(AvbOps* ops ATTRIBUTE_UNUSED,
-                                                 bool* out_is_unlocked) {
+static AvbIOResult no_op_read_is_device_unlocked(AvbOps* ops ATTRIBUTE_UNUSED,
+                                                bool* out_is_unlocked) {
     // The function is for bootloader to update the value into
     // androidboot.vbmeta.device_state in kernel cmdline.
     // In user-space, returns true as we don't need to update it anymore.
@@ -85,9 +85,9 @@
     return AVB_IO_RESULT_OK;
 }
 
-static AvbIOResult dummy_get_unique_guid_for_partition(AvbOps* ops ATTRIBUTE_UNUSED,
-                                                       const char* partition ATTRIBUTE_UNUSED,
-                                                       char* guid_buf, size_t guid_buf_size) {
+static AvbIOResult no_op_get_unique_guid_for_partition(AvbOps* ops ATTRIBUTE_UNUSED,
+                                                      const char* partition ATTRIBUTE_UNUSED,
+                                                      char* guid_buf, size_t guid_buf_size) {
     // The function is for bootloader to set the correct UUID
     // for a given partition in kernel cmdline.
     // In user-space, returns a faking one as we don't need to update
@@ -96,9 +96,9 @@
     return AVB_IO_RESULT_OK;
 }
 
-static AvbIOResult dummy_get_size_of_partition(AvbOps* ops ATTRIBUTE_UNUSED,
-                                               const char* partition ATTRIBUTE_UNUSED,
-                                               uint64_t* out_size_num_byte) {
+static AvbIOResult no_op_get_size_of_partition(AvbOps* ops ATTRIBUTE_UNUSED,
+                                              const char* partition ATTRIBUTE_UNUSED,
+                                              uint64_t* out_size_num_byte) {
     // The function is for bootloader to load entire content of AVB HASH partitions.
     // In user-space, returns 0 as we only need to set up AVB HASHTHREE partitions.
     *out_size_num_byte = 0;
@@ -123,15 +123,15 @@
     // We only need to provide the implementation of read_from_partition()
     // operation since that's all what is being used by the avb_slot_verify().
     // Other I/O operations are only required in bootloader but not in
-    // user-space so we set them as dummy operations. Also zero the entire
+    // user-space so we set them as no-op operations. Also zero the entire
     // struct so operations added in the future will be set to NULL.
     memset(&avb_ops_, 0, sizeof(AvbOps));
     avb_ops_.read_from_partition = read_from_partition;
-    avb_ops_.read_rollback_index = dummy_read_rollback_index;
-    avb_ops_.validate_vbmeta_public_key = dummy_validate_vbmeta_public_key;
-    avb_ops_.read_is_device_unlocked = dummy_read_is_device_unlocked;
-    avb_ops_.get_unique_guid_for_partition = dummy_get_unique_guid_for_partition;
-    avb_ops_.get_size_of_partition = dummy_get_size_of_partition;
+    avb_ops_.read_rollback_index = no_op_read_rollback_index;
+    avb_ops_.validate_vbmeta_public_key = no_op_validate_vbmeta_public_key;
+    avb_ops_.read_is_device_unlocked = no_op_read_is_device_unlocked;
+    avb_ops_.get_unique_guid_for_partition = no_op_get_unique_guid_for_partition;
+    avb_ops_.get_size_of_partition = no_op_get_size_of_partition;
 
     // Sets user_data for GetInstanceFromAvbOps() to convert it back to FsManagerAvbOps.
     avb_ops_.user_data = this;
diff --git a/fs_mgr/libfs_avb/fs_avb.cpp b/fs_mgr/libfs_avb/fs_avb.cpp
index 5d504ab..49333a1 100644
--- a/fs_mgr/libfs_avb/fs_avb.cpp
+++ b/fs_mgr/libfs_avb/fs_avb.cpp
@@ -226,7 +226,7 @@
             return nullptr;
     }
 
-    // Sanity check here because we have to use vbmeta_images_[0] below.
+    // Validity check here because we have to use vbmeta_images_[0] below.
     if (avb_handle->vbmeta_images_.size() < 1) {
         LERROR << "LoadAndVerifyVbmetaByPartition failed, no vbmeta loaded";
         return nullptr;
@@ -405,11 +405,11 @@
     //   - AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION (UNLOCKED only).
     //     Might occur in either the top-level vbmeta or a chained vbmeta.
     //   - AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED (UNLOCKED only).
-    //     Could only occur in a chained vbmeta. Because we have *dummy* operations in
+    //     Could only occur in a chained vbmeta. Because we have *no-op* operations in
     //     FsManagerAvbOps such that avb_ops->validate_vbmeta_public_key() used to validate
     //     the public key of the top-level vbmeta always pass in userspace here.
     //
-    // The following verify result won't happen, because the *dummy* operation
+    // The following verify result won't happen, because the *no-op* operation
     // avb_ops->read_rollback_index() always returns the minimum value zero. So rollbacked
     // vbmeta images, which should be caught in the bootloader stage, won't be detected here.
     //   - AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX
diff --git a/fs_mgr/libfs_avb/tests/util_test.cpp b/fs_mgr/libfs_avb/tests/util_test.cpp
index 5c388aa..a52a00d 100644
--- a/fs_mgr/libfs_avb/tests/util_test.cpp
+++ b/fs_mgr/libfs_avb/tests/util_test.cpp
@@ -222,7 +222,7 @@
     base::FilePath test_dir;
     ASSERT_TRUE(base::CreateTemporaryDirInDir(tmp_dir, "list-file-tests.", &test_dir));
 
-    // Generates dummy files to list.
+    // Generates test files to list.
     base::FilePath file_path_1 = test_dir.Append("1.txt");
     ASSERT_TRUE(base::WriteFile(file_path_1, "1", 1));
     base::FilePath file_path_2 = test_dir.Append("2.txt");
@@ -253,7 +253,7 @@
     base::FilePath test_dir;
     ASSERT_TRUE(base::CreateTemporaryDirInDir(tmp_dir, "list-file-tests.", &test_dir));
 
-    // Generates dummy files to list.
+    // Generates test files to list.
     base::FilePath file_path_1 = test_dir.Append("1.txt");
     ASSERT_TRUE(base::WriteFile(file_path_1, "1", 1));
     base::FilePath file_path_2 = test_dir.Append("2.txt");
@@ -281,7 +281,7 @@
     base::FilePath tmp_dir;
     ASSERT_TRUE(GetTempDir(&tmp_dir));
 
-    // Generates dummy files to list.
+    // Generates test files to list.
     base::FilePath no_such_dir = tmp_dir.Append("not_such_dir");
 
     auto fail = ListFiles(no_such_dir.value());
diff --git a/fs_mgr/liblp/builder_test.cpp b/fs_mgr/liblp/builder_test.cpp
index a21e09e..e4b617a 100644
--- a/fs_mgr/liblp/builder_test.cpp
+++ b/fs_mgr/liblp/builder_test.cpp
@@ -234,7 +234,7 @@
         EXPECT_EQ(lba, aligned_lba);
     }
 
-    // Sanity check one extent.
+    // Check one extent.
     EXPECT_EQ(exported->extents.back().target_data, 3072);
 }
 
diff --git a/fs_mgr/liblp/device_test.cpp b/fs_mgr/liblp/device_test.cpp
index 6af9d94..236fd8d 100644
--- a/fs_mgr/liblp/device_test.cpp
+++ b/fs_mgr/liblp/device_test.cpp
@@ -47,7 +47,7 @@
     BlockDeviceInfo device_info;
     ASSERT_TRUE(opener.GetInfo(fs_mgr_get_super_partition_name(), &device_info));
 
-    // Sanity check that the device doesn't give us some weird inefficient
+    // Check that the device doesn't give us some weird inefficient
     // alignment.
     EXPECT_EQ(device_info.alignment % LP_SECTOR_SIZE, 0);
     EXPECT_EQ(device_info.logical_block_size % LP_SECTOR_SIZE, 0);
diff --git a/fs_mgr/liblp/partition_opener.cpp b/fs_mgr/liblp/partition_opener.cpp
index 1d4db85..3d3dde6 100644
--- a/fs_mgr/liblp/partition_opener.cpp
+++ b/fs_mgr/liblp/partition_opener.cpp
@@ -49,7 +49,7 @@
         // Dynamic System Update is installed to an sdcard, which won't be in
         // the boot device list.
         //
-        // We whitelist because most devices in /dev/block are not valid for
+        // mmcblk* is allowed because most devices in /dev/block are not valid for
         // storing fiemaps.
         if (android::base::StartsWith(path, "mmcblk")) {
             return "/dev/block/" + path;
diff --git a/fs_mgr/liblp/reader.cpp b/fs_mgr/liblp/reader.cpp
index e6fd9f7..24ccc0f 100644
--- a/fs_mgr/liblp/reader.cpp
+++ b/fs_mgr/liblp/reader.cpp
@@ -174,7 +174,7 @@
         return false;
     }
 
-    // Do basic sanity checks before computing the checksum.
+    // Do basic validity checks before computing the checksum.
     if (header.magic != LP_METADATA_HEADER_MAGIC) {
         LERROR << "Logical partition metadata has invalid magic value.";
         return false;
@@ -255,7 +255,7 @@
 
     LpMetadataHeader& header = metadata->header;
 
-    // Sanity check the table size.
+    // Check the table size.
     if (header.tables_size > geometry.metadata_max_size) {
         LERROR << "Invalid partition metadata header table size.";
         return nullptr;
diff --git a/fs_mgr/liblp/writer.cpp b/fs_mgr/liblp/writer.cpp
index 8bf1ee9..2708efa 100644
--- a/fs_mgr/liblp/writer.cpp
+++ b/fs_mgr/liblp/writer.cpp
@@ -81,8 +81,8 @@
     return header_blob + tables;
 }
 
-// Perform sanity checks so we don't accidentally overwrite valid metadata
-// with potentially invalid metadata, or random partition data with metadata.
+// Perform checks so we don't accidentally overwrite valid metadata with
+// potentially invalid metadata, or random partition data with metadata.
 static bool ValidateAndSerializeMetadata([[maybe_unused]] const IPartitionOpener& opener,
                                          const LpMetadata& metadata, const std::string& slot_suffix,
                                          std::string* blob) {
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index 3c2c776..a4a3150 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -553,9 +553,8 @@
     // This should only be called in recovery.
     bool UnmapAllPartitions();
 
-    // Sanity check no snapshot overflows. Note that this returns false negatives if the snapshot
-    // overflows, then is remapped and not written afterwards. Hence, the function may only serve
-    // as a sanity check.
+    // Check no snapshot overflows. Note that this returns false negatives if the snapshot
+    // overflows, then is remapped and not written afterwards.
     bool EnsureNoOverflowSnapshot(LockedFile* lock);
 
     enum class Slot { Unknown, Source, Target };
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 7488bda..b49f99e 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -300,9 +300,9 @@
         LOG(ERROR) << "SnapshotStatus has no name.";
         return false;
     }
-    // Sanity check these sizes. Like liblp, we guarantee the partition size
-    // is respected, which means it has to be sector-aligned. (This guarantee
-    // is useful for locating avb footers correctly). The COW file size, however,
+    // Check these sizes. Like liblp, we guarantee the partition size is
+    // respected, which means it has to be sector-aligned. (This guarantee is
+    // useful for locating avb footers correctly). The COW file size, however,
     // can be arbitrarily larger than specified, so we can safely round it up.
     if (status->device_size() % kSectorSize != 0) {
         LOG(ERROR) << "Snapshot " << status->name()
@@ -351,7 +351,6 @@
     }
 
     // The COW file size should have been rounded up to the nearest sector in CreateSnapshot.
-    // Sanity check this.
     if (status.cow_file_size() % kSectorSize != 0) {
         LOG(ERROR) << "Snapshot " << name << " COW file size is not a multiple of the sector size: "
                    << status.cow_file_size();
diff --git a/fs_mgr/libsnapshot/snapshot_fuzz.cpp b/fs_mgr/libsnapshot/snapshot_fuzz.cpp
index 5b145c3..aced3ed 100644
--- a/fs_mgr/libsnapshot/snapshot_fuzz.cpp
+++ b/fs_mgr/libsnapshot/snapshot_fuzz.cpp
@@ -141,7 +141,7 @@
                        const RecoveryCreateSnapshotDevicesArgs& args) {
     std::unique_ptr<AutoDevice> device;
     if (args.has_metadata_device_object()) {
-        device = std::make_unique<DummyAutoDevice>(args.metadata_mounted());
+        device = std::make_unique<NoOpAutoDevice>(args.metadata_mounted());
     }
     return snapshot->RecoveryCreateSnapshotDevices(device);
 }
diff --git a/fs_mgr/libsnapshot/snapshot_fuzz_utils.h b/fs_mgr/libsnapshot/snapshot_fuzz_utils.h
index fa327b8..5319e69 100644
--- a/fs_mgr/libsnapshot/snapshot_fuzz_utils.h
+++ b/fs_mgr/libsnapshot/snapshot_fuzz_utils.h
@@ -35,9 +35,9 @@
 class AutoMemBasedDir;
 class SnapshotFuzzDeviceInfo;
 
-class DummyAutoDevice : public AutoDevice {
+class NoOpAutoDevice : public AutoDevice {
   public:
-    DummyAutoDevice(bool mounted) : AutoDevice(mounted ? "dummy" : "") {}
+    NoOpAutoDevice(bool mounted) : AutoDevice(mounted ? "no_op" : "") {}
 };
 
 struct SnapshotTestModule {
diff --git a/fs_mgr/libsnapshot/snapshot_metadata_updater.cpp b/fs_mgr/libsnapshot/snapshot_metadata_updater.cpp
index 051584c..12101a2 100644
--- a/fs_mgr/libsnapshot/snapshot_metadata_updater.cpp
+++ b/fs_mgr/libsnapshot/snapshot_metadata_updater.cpp
@@ -173,9 +173,9 @@
         if (iter != groups_.end()) {
             continue;
         }
-        // Update package metadata doesn't have this group. Before deleting it, sanity check that it
-        // doesn't have any partitions left. Update metadata shouldn't assign any partitions to this
-        // group, so all partitions that originally belong to this group should be moved by
+        // Update package metadata doesn't have this group. Before deleting it, check that it
+        // doesn't have any partitions left. Update metadata shouldn't assign any partitions to
+        // this group, so all partitions that originally belong to this group should be moved by
         // MovePartitionsToDefault at this point.
         auto existing_partitions_in_group = builder_->ListPartitionsInGroup(existing_group_name);
         if (!existing_partitions_in_group.empty()) {
diff --git a/init/init.cpp b/init/init.cpp
index ba880ea..cb5bbba 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -18,6 +18,7 @@
 
 #include <dirent.h>
 #include <fcntl.h>
+#include <paths.h>
 #include <pthread.h>
 #include <signal.h>
 #include <stdlib.h>
@@ -727,6 +728,12 @@
     InitSecondStageLogging(argv);
     LOG(INFO) << "init second stage started!";
 
+    // Update $PATH in the case the second stage init is newer than first stage init, where it is
+    // first set.
+    if (setenv("PATH", _PATH_DEFPATH, 1) != 0) {
+        PLOG(FATAL) << "Could not set $PATH to '" << _PATH_DEFPATH << "' in second stage";
+    }
+
     // Init should not crash because of a dependence on any other process, therefore we ignore
     // SIGPIPE and handle EPIPE at the call site directly.  Note that setting a signal to SIG_IGN
     // is inherited across exec, but custom signal handlers are not.  Since we do not want to
diff --git a/init/uevent_listener.cpp b/init/uevent_listener.cpp
index d8d9b36..7cd396a 100644
--- a/init/uevent_listener.cpp
+++ b/init/uevent_listener.cpp
@@ -95,20 +95,18 @@
     fcntl(device_fd_, F_SETFL, O_NONBLOCK);
 }
 
-bool UeventListener::ReadUevent(Uevent* uevent) const {
+ReadUeventResult UeventListener::ReadUevent(Uevent* uevent) const {
     char msg[UEVENT_MSG_LEN + 2];
     int n = uevent_kernel_multicast_recv(device_fd_, msg, UEVENT_MSG_LEN);
     if (n <= 0) {
         if (errno != EAGAIN && errno != EWOULDBLOCK) {
             PLOG(ERROR) << "Error reading from Uevent Fd";
         }
-        return false;
+        return ReadUeventResult::kFailed;
     }
     if (n >= UEVENT_MSG_LEN) {
         LOG(ERROR) << "Uevent overflowed buffer, discarding";
-        // Return true here even if we discard as we may have more uevents pending and we
-        // want to keep processing them.
-        return true;
+        return ReadUeventResult::kInvalid;
     }
 
     msg[n] = '\0';
@@ -116,7 +114,7 @@
 
     ParseEvent(msg, uevent);
 
-    return true;
+    return ReadUeventResult::kSuccess;
 }
 
 // RegenerateUevents*() walks parts of the /sys tree and pokes the uevent files to cause the kernel
@@ -137,7 +135,10 @@
         close(fd);
 
         Uevent uevent;
-        while (ReadUevent(&uevent)) {
+        ReadUeventResult result;
+        while ((result = ReadUevent(&uevent)) != ReadUeventResult::kFailed) {
+            // Skip processing the uevent if it is invalid.
+            if (result == ReadUeventResult::kInvalid) continue;
             if (callback(uevent) == ListenerAction::kStop) return ListenerAction::kStop;
         }
     }
@@ -212,7 +213,10 @@
             // We're non-blocking, so if we receive a poll event keep processing until
             // we have exhausted all uevent messages.
             Uevent uevent;
-            while (ReadUevent(&uevent)) {
+            ReadUeventResult result;
+            while ((result = ReadUevent(&uevent)) != ReadUeventResult::kFailed) {
+                // Skip processing the uevent if it is invalid.
+                if (result == ReadUeventResult::kInvalid) continue;
                 if (callback(uevent) == ListenerAction::kStop) return;
             }
         }
diff --git a/init/uevent_listener.h b/init/uevent_listener.h
index aea094e..2772860 100644
--- a/init/uevent_listener.h
+++ b/init/uevent_listener.h
@@ -27,7 +27,7 @@
 
 #include "uevent.h"
 
-#define UEVENT_MSG_LEN 2048
+#define UEVENT_MSG_LEN 8192
 
 namespace android {
 namespace init {
@@ -37,6 +37,12 @@
     kContinue,  // Continue regenerating uevents as we haven't seen the one(s) we're interested in.
 };
 
+enum class ReadUeventResult {
+    kSuccess = 0,  // Uevent was successfully read.
+    kFailed,       // Uevent reading has failed.
+    kInvalid,      // An Invalid Uevent was read (like say, the msg received is >= UEVENT_MSG_LEN).
+};
+
 using ListenerCallback = std::function<ListenerAction(const Uevent&)>;
 
 class UeventListener {
@@ -50,7 +56,7 @@
               const std::optional<std::chrono::milliseconds> relative_timeout = {}) const;
 
   private:
-    bool ReadUevent(Uevent* uevent) const;
+    ReadUeventResult ReadUevent(Uevent* uevent) const;
     ListenerAction RegenerateUeventsForDir(DIR* d, const ListenerCallback& callback) const;
 
     android::base::unique_fd device_fd_;
diff --git a/logd/Android.bp b/logd/Android.bp
index 036cb7e..fe97871 100644
--- a/logd/Android.bp
+++ b/logd/Android.bp
@@ -180,3 +180,23 @@
         "vts10",
     ],
 }
+
+cc_binary {
+    name: "replay_messages",
+    defaults: ["logd_defaults"],
+    host_supported: true,
+
+    srcs: [
+        "ReplayMessages.cpp",
+    ],
+
+    static_libs: [
+        "libbase",
+        "libcutils",
+        "liblog",
+        "liblogd",
+        "libselinux",
+        "libz",
+        "libzstd",
+    ],
+}
diff --git a/logd/LogStatistics.cpp b/logd/LogStatistics.cpp
index 1705d48..87069b3 100644
--- a/logd/LogStatistics.cpp
+++ b/logd/LogStatistics.cpp
@@ -26,8 +26,10 @@
 #include <unistd.h>
 
 #include <list>
+#include <vector>
 
 #include <android-base/logging.h>
+#include <android-base/strings.h>
 #include <private/android_logger.h>
 
 #include "LogBufferElement.h"
@@ -61,7 +63,8 @@
     return std::string(msg, len);
 }
 
-LogStatistics::LogStatistics(bool enable_statistics, bool track_total_size)
+LogStatistics::LogStatistics(bool enable_statistics, bool track_total_size,
+                             std::optional<log_time> start_time)
     : enable(enable_statistics), track_total_size_(track_total_size) {
     log_time now(CLOCK_REALTIME);
     log_id_for_each(id) {
@@ -70,8 +73,13 @@
         mDroppedElements[id] = 0;
         mSizesTotal[id] = 0;
         mElementsTotal[id] = 0;
-        mOldest[id] = now;
-        mNewest[id] = now;
+        if (start_time) {
+            mOldest[id] = *start_time;
+            mNewest[id] = *start_time;
+        } else {
+            mOldest[id] = now;
+            mNewest[id] = now;
+        }
         mNewestDropped[id] = now;
     }
 }
@@ -784,6 +792,31 @@
     return output;
 }
 
+std::string LogStatistics::ReportInteresting() const {
+    auto lock = std::lock_guard{lock_};
+
+    std::vector<std::string> items;
+
+    log_id_for_each(i) { items.emplace_back(std::to_string(mElements[i])); }
+
+    log_id_for_each(i) { items.emplace_back(std::to_string(mSizes[i])); }
+
+    log_id_for_each(i) {
+        items.emplace_back(std::to_string(overhead_[i] ? *overhead_[i] : mSizes[i]));
+    }
+
+    log_id_for_each(i) {
+        uint64_t oldest = mOldest[i].msec() / 1000;
+        uint64_t newest = mNewest[i].msec() / 1000;
+
+        int span = newest - oldest;
+
+        items.emplace_back(std::to_string(span));
+    }
+
+    return android::base::Join(items, ",");
+}
+
 std::string LogStatistics::Format(uid_t uid, pid_t pid, unsigned int logMask) const {
     auto lock = std::lock_guard{lock_};
 
diff --git a/logd/LogStatistics.h b/logd/LogStatistics.h
index d440a8c..e222d3f 100644
--- a/logd/LogStatistics.h
+++ b/logd/LogStatistics.h
@@ -515,7 +515,8 @@
     }
 
   public:
-    LogStatistics(bool enable_statistics, bool track_total_size);
+    LogStatistics(bool enable_statistics, bool track_total_size,
+                  std::optional<log_time> start_time = {});
 
     void AddTotal(log_id_t log_id, uint16_t size) EXCLUDES(lock_);
 
@@ -556,6 +557,7 @@
         return SizesTotal;
     }
 
+    std::string ReportInteresting() const EXCLUDES(lock_);
     std::string Format(uid_t uid, pid_t pid, unsigned int logMask) const EXCLUDES(lock_);
 
     const char* PidToName(pid_t pid) const EXCLUDES(lock_);
diff --git a/logd/README.replay.md b/logd/README.replay.md
new file mode 100644
index 0000000..5f7ec9e
--- /dev/null
+++ b/logd/README.replay.md
@@ -0,0 +1,46 @@
+logd can record and replay log messages for offline analysis.
+
+Recording Messages
+------------------
+
+logd has a `RecordingLogBuffer` buffer that records messages to /data/misc/logd/recorded-messages.
+It stores messages in memory until that file is accessible, in order to capture all messages since
+the beginning of boot.  It is only meant for logging developers to use and must be manually enabled
+in by adding `RecordingLogBuffer.cpp` to `Android.bp` and setting
+`log_buffer = new SimpleLogBuffer(&reader_list, &log_tags, &log_statistics);` in `main.cpp`.
+
+Recording messages may delay the Log() function from completing and it is highly recommended to make
+the logd socket in `liblog` blocking, by removing `SOCK_NONBLOCK` from the `socket()` call in
+`liblog/logd_writer.cpp`.
+
+Replaying Messages
+------------------
+
+Recorded messages can be replayed offline with the `replay_messages` tool.  It runs on host and
+device and supports the following options:
+
+1. `interesting` - this prints 'interesting' statistics for each of the log buffer types (simple,
+   chatty, serialized).  The statistics are:
+    1. Log Entry Count
+    2. Size (the uncompressed size of the log messages in bytes)
+    3. Overhead (the total cost of the log messages in memory in bytes)
+    4. Range (the range of time that the logs cover in seconds)
+2. `memory_usage BUFFER_TYPE` - this prints the memory usage (sum of private dirty pages of the
+  `replay_messages` process).  Note that the input file is mmap()'ed as RO/Shared so it does not
+  appear in these dirty pages, and a baseline is taken before allocating the log buffers, so only
+  their contributions are measured.  The tool outputs the memory usage every 100,000 messages.
+3. `latency BUFFER_TYPE` - this prints statistics of the latency of the Log() function for the given
+  buffer type.  It specifically prints the 1st, 2nd, and 3rd quartiles; the 95th, 99th, and 99.99th
+  percentiles; and the maximum latency.
+4. `print_logs BUFFER_TYPE [buffers] [print_point]` - this prints the logs as processed by the given
+  buffer_type from the buffers specified by `buffers` starting after the number of logs specified by
+  `print_point` have been logged.  This acts as if a user called `logcat` immediately after the
+  specified logs have been logged, which is particularly useful since it will show the chatty
+  pruning messages at that point.  It additionally prints the statistics from `logcat -S` after the
+  logs.
+  `buffers` is a comma separated list of the numeric buffer id values from `<android/log.h>`.  For
+  example, `0,1,3` represents the main, radio, and system buffers.  It can can also be `all`.
+  `print_point` is an positive integer.  If it is unspecified, logs are printed after the entire
+  input file is consumed.
+5. `nothing BUFFER_TYPE` - this does nothing other than read the input file and call Log() for the
+  given buffer type.  This is used for profiling CPU usage of strictly the log buffer.
diff --git a/logd/RecordedLogMessage.h b/logd/RecordedLogMessage.h
new file mode 100644
index 0000000..f18c422
--- /dev/null
+++ b/logd/RecordedLogMessage.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <inttypes.h>
+
+#include <log/log_time.h>
+
+struct __attribute__((packed)) RecordedLogMessage {
+    uint32_t uid;
+    uint32_t pid;
+    uint32_t tid;
+    log_time realtime;
+    uint16_t msg_len;
+    uint8_t log_id;
+};
diff --git a/logd/RecordingLogBuffer.cpp b/logd/RecordingLogBuffer.cpp
new file mode 100644
index 0000000..f5991f3
--- /dev/null
+++ b/logd/RecordingLogBuffer.cpp
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "RecordingLogBuffer.h"
+
+#include <android-base/file.h>
+
+static void WriteLogMessage(int fd, const RecordedLogMessage& meta, const std::string& msg) {
+    android::base::WriteFully(fd, &meta, sizeof(meta));
+    android::base::WriteFully(fd, msg.c_str(), meta.msg_len);
+}
+
+void RecordingLogBuffer::RecordLogMessage(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid,
+                                          pid_t tid, const char* msg, uint16_t len) {
+    auto lock = std::lock_guard{lock_};
+    if (len > LOGGER_ENTRY_MAX_PAYLOAD) {
+        len = LOGGER_ENTRY_MAX_PAYLOAD;
+    }
+
+    RecordedLogMessage recorded_log_message = {
+            .uid = uid,
+            .pid = static_cast<uint32_t>(pid),
+            .tid = static_cast<uint32_t>(tid),
+            .realtime = realtime,
+            .msg_len = len,
+            .log_id = static_cast<uint8_t>(log_id),
+    };
+
+    if (!fd_.ok()) {
+        fd_.reset(open("/data/misc/logd/recorded-messages",
+                       O_WRONLY | O_CREAT | O_APPEND | O_CLOEXEC, 0666));
+        if (!fd_.ok()) {
+            since_boot_messages_.emplace_back(recorded_log_message, std::string(msg, len));
+            return;
+        } else {
+            for (const auto& [meta, msg] : since_boot_messages_) {
+                WriteLogMessage(fd_.get(), meta, msg);
+            }
+        }
+    }
+
+    WriteLogMessage(fd_.get(), recorded_log_message, std::string(msg, len));
+}
+
+int RecordingLogBuffer::Log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid,
+                            const char* msg, uint16_t len) {
+    RecordLogMessage(log_id, realtime, uid, pid, tid, msg, len);
+    return SimpleLogBuffer::Log(log_id, realtime, uid, pid, tid, msg, len);
+}
\ No newline at end of file
diff --git a/logd/RecordingLogBuffer.h b/logd/RecordingLogBuffer.h
new file mode 100644
index 0000000..49a0aba
--- /dev/null
+++ b/logd/RecordingLogBuffer.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "SimpleLogBuffer.h"
+
+#include <string>
+#include <tuple>
+#include <vector>
+
+#include <android-base/unique_fd.h>
+
+#include "RecordedLogMessage.h"
+
+class RecordingLogBuffer : public SimpleLogBuffer {
+  public:
+    RecordingLogBuffer(LogReaderList* reader_list, LogTags* tags, LogStatistics* stats)
+        : SimpleLogBuffer(reader_list, tags, stats) {}
+
+    int Log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid, const char* msg,
+            uint16_t len) override;
+
+  private:
+    void RecordLogMessage(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid,
+                          const char* msg, uint16_t len);
+
+    std::vector<std::pair<RecordedLogMessage, std::string>> since_boot_messages_;
+    android::base::unique_fd fd_;
+};
diff --git a/logd/ReplayMessages.cpp b/logd/ReplayMessages.cpp
new file mode 100644
index 0000000..73b0bd0
--- /dev/null
+++ b/logd/ReplayMessages.cpp
@@ -0,0 +1,454 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <inttypes.h>
+
+#include <chrono>
+#include <map>
+
+#include <android-base/file.h>
+#include <android-base/mapped_file.h>
+#include <android-base/parseint.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+#include <android/log.h>
+#include <log/log_time.h>
+#include <log/logprint.h>
+
+#include "ChattyLogBuffer.h"
+#include "LogBuffer.h"
+#include "LogStatistics.h"
+#include "RecordedLogMessage.h"
+#include "SerializedLogBuffer.h"
+#include "SimpleLogBuffer.h"
+
+using android::base::MappedFile;
+using android::base::ParseInt;
+using android::base::ParseUint;
+using android::base::Split;
+
+#ifndef __ANDROID__
+// This is hard coded to 1MB on host.  On device use persist.logd.size to configure.
+unsigned long __android_logger_get_buffer_size(log_id_t) {
+    return 1 * 1024 * 1024;
+}
+
+bool __android_logger_valid_buffer_size(unsigned long) {
+    return true;
+}
+#endif
+
+char* android::uidToName(uid_t) {
+    return nullptr;
+}
+
+static size_t GetPrivateDirty() {
+    // Allocate once and hope that we don't need to reallocate >40000, to prevent heap fragmentation
+    static std::string smaps(40000, '\0');
+    android::base::ReadFileToString("/proc/self/smaps", &smaps);
+
+    size_t result = 0;
+    size_t base = 0;
+    size_t found;
+    while (true) {
+        found = smaps.find("Private_Dirty:", base);
+        if (found == smaps.npos) break;
+
+        found += sizeof("Private_Dirty:");
+
+        result += atoi(&smaps[found]);
+
+        base = found + 1;
+    }
+
+    return result;
+}
+
+static AndroidLogFormat* GetLogFormat() {
+    static AndroidLogFormat* format = [] {
+        auto* format = android_log_format_new();
+        android_log_setPrintFormat(format, android_log_formatFromString("threadtime"));
+        android_log_setPrintFormat(format, android_log_formatFromString("uid"));
+        return format;
+    }();
+    return format;
+}
+
+static void PrintMessage(struct log_msg* buf) {
+    bool is_binary =
+            buf->id() == LOG_ID_EVENTS || buf->id() == LOG_ID_STATS || buf->id() == LOG_ID_SECURITY;
+
+    AndroidLogEntry entry;
+    int err;
+    if (is_binary) {
+        char binaryMsgBuf[1024];
+        err = android_log_processBinaryLogBuffer(&buf->entry, &entry, nullptr, binaryMsgBuf,
+                                                 sizeof(binaryMsgBuf));
+    } else {
+        err = android_log_processLogBuffer(&buf->entry, &entry);
+    }
+    if (err < 0) {
+        fprintf(stderr, "Error parsing log message\n");
+    }
+
+    android_log_printLogLine(GetLogFormat(), STDOUT_FILENO, &entry);
+}
+
+static log_time GetFirstTimeStamp(const MappedFile& recorded_messages) {
+    if (sizeof(RecordedLogMessage) >= recorded_messages.size()) {
+        fprintf(stderr, "At least one log message must be present in the input\n");
+        exit(1);
+    }
+
+    auto* meta = reinterpret_cast<RecordedLogMessage*>(recorded_messages.data());
+    return meta->realtime;
+}
+
+class StdoutWriter : public LogWriter {
+  public:
+    StdoutWriter() : LogWriter(0, true) {}
+    bool Write(const logger_entry& entry, const char* message) override {
+        struct log_msg log_msg;
+        log_msg.entry = entry;
+        if (log_msg.entry.len > LOGGER_ENTRY_MAX_PAYLOAD) {
+            fprintf(stderr, "payload too large %" PRIu16, log_msg.entry.len);
+            exit(1);
+        }
+        memcpy(log_msg.msg(), message, log_msg.entry.len);
+
+        PrintMessage(&log_msg);
+
+        return true;
+    }
+
+    std::string name() const override { return "stdout writer"; }
+};
+
+class Operation {
+  public:
+    virtual ~Operation() {}
+
+    virtual void Begin() {}
+    virtual void Log(const RecordedLogMessage& meta, const char* msg) = 0;
+    virtual void End() {}
+};
+
+class PrintInteresting : public Operation {
+  public:
+    PrintInteresting(log_time first_log_timestamp)
+        : stats_simple_{false, false, first_log_timestamp},
+          stats_chatty_{false, false, first_log_timestamp},
+          stats_serialized_{false, true, first_log_timestamp} {}
+
+    void Begin() override {
+        printf("message_count,simple_main_lines,simple_radio_lines,simple_events_lines,simple_"
+               "system_lines,simple_crash_lines,simple_stats_lines,simple_security_lines,simple_"
+               "kernel_lines,simple_main_size,simple_radio_size,simple_events_size,simple_system_"
+               "size,simple_crash_size,simple_stats_size,simple_security_size,simple_kernel_size,"
+               "simple_main_overhead,simple_radio_overhead,simple_events_overhead,simple_system_"
+               "overhead,simple_crash_overhead,simple_stats_overhead,simple_security_overhead,"
+               "simple_kernel_overhead,simple_main_range,simple_radio_range,simple_events_range,"
+               "simple_system_range,simple_crash_range,simple_stats_range,simple_security_range,"
+               "simple_kernel_range,chatty_main_lines,chatty_radio_lines,chatty_events_lines,"
+               "chatty_system_lines,chatty_crash_lines,chatty_stats_lines,chatty_security_lines,"
+               "chatty_"
+               "kernel_lines,chatty_main_size,chatty_radio_size,chatty_events_size,chatty_system_"
+               "size,chatty_crash_size,chatty_stats_size,chatty_security_size,chatty_kernel_size,"
+               "chatty_main_overhead,chatty_radio_overhead,chatty_events_overhead,chatty_system_"
+               "overhead,chatty_crash_overhead,chatty_stats_overhead,chatty_security_overhead,"
+               "chatty_kernel_overhead,chatty_main_range,chatty_radio_range,chatty_events_range,"
+               "chatty_system_range,chatty_crash_range,chatty_stats_range,chatty_security_range,"
+               "chatty_kernel_range,serialized_main_lines,serialized_radio_lines,serialized_events_"
+               "lines,serialized_"
+               "system_lines,serialized_crash_lines,serialized_stats_lines,serialized_security_"
+               "lines,serialized_"
+               "kernel_lines,serialized_main_size,serialized_radio_size,serialized_events_size,"
+               "serialized_system_"
+               "size,serialized_crash_size,serialized_stats_size,serialized_security_size,"
+               "serialized_kernel_size,"
+               "serialized_main_overhead,serialized_radio_overhead,serialized_events_overhead,"
+               "serialized_system_"
+               "overhead,serialized_crash_overhead,serialized_stats_overhead,serialized_security_"
+               "overhead,"
+               "serialized_kernel_overhead,serialized_main_range,serialized_radio_range,serialized_"
+               "events_range,"
+               "serialized_system_range,serialized_crash_range,serialized_stats_range,serialized_"
+               "security_range,"
+               "serialized_kernel_range\n");
+    }
+
+    void Log(const RecordedLogMessage& meta, const char* msg) override {
+        simple_log_buffer_.Log(static_cast<log_id_t>(meta.log_id), meta.realtime, meta.uid,
+                               meta.pid, meta.tid, msg, meta.msg_len);
+
+        chatty_log_buffer_.Log(static_cast<log_id_t>(meta.log_id), meta.realtime, meta.uid,
+                               meta.pid, meta.tid, msg, meta.msg_len);
+
+        serialized_log_buffer_.Log(static_cast<log_id_t>(meta.log_id), meta.realtime, meta.uid,
+                                   meta.pid, meta.tid, msg, meta.msg_len);
+
+        if (num_message_ % 10000 == 0) {
+            printf("%" PRIu64 ",%s,%s,%s\n", num_message_,
+                   stats_simple_.ReportInteresting().c_str(),
+                   stats_chatty_.ReportInteresting().c_str(),
+                   stats_serialized_.ReportInteresting().c_str());
+        }
+
+        num_message_++;
+    }
+
+  private:
+    uint64_t num_message_ = 1;
+
+    LogReaderList reader_list_;
+    LogTags tags_;
+    PruneList prune_list_;
+
+    LogStatistics stats_simple_;
+    SimpleLogBuffer simple_log_buffer_{&reader_list_, &tags_, &stats_simple_};
+
+    LogStatistics stats_chatty_;
+    ChattyLogBuffer chatty_log_buffer_{&reader_list_, &tags_, &prune_list_, &stats_chatty_};
+
+    LogStatistics stats_serialized_;
+    SerializedLogBuffer serialized_log_buffer_{&reader_list_, &tags_, &stats_serialized_};
+};
+
+class SingleBufferOperation : public Operation {
+  public:
+    SingleBufferOperation(log_time first_log_timestamp, const char* buffer) {
+        if (!strcmp(buffer, "simple")) {
+            stats_.reset(new LogStatistics{false, false, first_log_timestamp});
+            log_buffer_.reset(new SimpleLogBuffer(&reader_list_, &tags_, stats_.get()));
+        } else if (!strcmp(buffer, "chatty")) {
+            stats_.reset(new LogStatistics{false, false, first_log_timestamp});
+            log_buffer_.reset(
+                    new ChattyLogBuffer(&reader_list_, &tags_, &prune_list_, stats_.get()));
+        } else if (!strcmp(buffer, "serialized")) {
+            stats_.reset(new LogStatistics{false, true, first_log_timestamp});
+            log_buffer_.reset(new SerializedLogBuffer(&reader_list_, &tags_, stats_.get()));
+        } else {
+            fprintf(stderr, "invalid log buffer type '%s'\n", buffer);
+            abort();
+        }
+    }
+
+    void Log(const RecordedLogMessage& meta, const char* msg) override {
+        PreOperation();
+        log_buffer_->Log(static_cast<log_id_t>(meta.log_id), meta.realtime, meta.uid, meta.pid,
+                         meta.tid, msg, meta.msg_len);
+
+        Operation();
+
+        num_message_++;
+    }
+
+    virtual void PreOperation() {}
+    virtual void Operation() {}
+
+  protected:
+    uint64_t num_message_ = 1;
+
+    LogReaderList reader_list_;
+    LogTags tags_;
+    PruneList prune_list_;
+
+    std::unique_ptr<LogStatistics> stats_;
+    std::unique_ptr<LogBuffer> log_buffer_;
+};
+
+class PrintMemory : public SingleBufferOperation {
+  public:
+    PrintMemory(log_time first_log_timestamp, const char* buffer)
+        : SingleBufferOperation(first_log_timestamp, buffer) {}
+
+    void Operation() override {
+        if (num_message_ % 100000 == 0) {
+            printf("%" PRIu64 ",%s\n", num_message_,
+                   std::to_string(GetPrivateDirty() - baseline_memory_).c_str());
+        }
+    }
+
+  private:
+    size_t baseline_memory_ = GetPrivateDirty();
+};
+
+class PrintLogs : public SingleBufferOperation {
+  public:
+    PrintLogs(log_time first_log_timestamp, const char* buffer, const char* buffers,
+              const char* print_point)
+        : SingleBufferOperation(first_log_timestamp, buffer) {
+        if (buffers != nullptr) {
+            if (strcmp(buffers, "all") != 0) {
+                std::vector<int> buffer_ids;
+                auto string_ids = Split(buffers, ",");
+                for (const auto& string_id : string_ids) {
+                    int result;
+                    if (!ParseInt(string_id, &result, 0, 7)) {
+                        fprintf(stderr, "Could not parse buffer_id '%s'\n", string_id.c_str());
+                        exit(1);
+                    }
+                    buffer_ids.emplace_back(result);
+                }
+                mask_ = 0;
+                for (const auto& buffer_id : buffer_ids) {
+                    mask_ |= 1 << buffer_id;
+                }
+            }
+        }
+        if (print_point != nullptr) {
+            uint64_t result = 0;
+            if (!ParseUint(print_point, &result)) {
+                fprintf(stderr, "Could not parse print point '%s'\n", print_point);
+                exit(1);
+            }
+            print_point_ = result;
+        }
+    }
+
+    void Operation() override {
+        if (print_point_ && num_message_ >= *print_point_) {
+            End();
+            exit(0);
+        }
+    }
+
+    void End() {
+        std::unique_ptr<LogWriter> test_writer(new StdoutWriter());
+        std::unique_ptr<FlushToState> flush_to_state = log_buffer_->CreateFlushToState(1, mask_);
+        log_buffer_->FlushTo(test_writer.get(), *flush_to_state, nullptr);
+
+        auto stats_string = stats_->Format(0, 0, mask_);
+        printf("%s\n", stats_string.c_str());
+    }
+
+  private:
+    LogMask mask_ = kLogMaskAll;
+    std::optional<uint64_t> print_point_;
+};
+
+class PrintLatency : public SingleBufferOperation {
+  public:
+    PrintLatency(log_time first_log_timestamp, const char* buffer)
+        : SingleBufferOperation(first_log_timestamp, buffer) {}
+
+    void PreOperation() override { operation_start_ = std::chrono::steady_clock::now(); }
+
+    void Operation() override {
+        auto end = std::chrono::steady_clock::now();
+        auto duration = (end - operation_start_).count();
+        durations_.emplace_back(duration);
+    }
+
+    void End() {
+        std::sort(durations_.begin(), durations_.end());
+        auto q1 = durations_.size() / 4;
+        auto q2 = durations_.size() / 2;
+        auto q3 = 3 * durations_.size() / 4;
+
+        auto p95 = 95 * durations_.size() / 100;
+        auto p99 = 99 * durations_.size() / 100;
+        auto p9999 = 9999 * durations_.size() / 10000;
+
+        printf("q1: %lld q2: %lld q3: %lld  p95: %lld p99: %lld p99.99: %lld  max: %lld\n",
+               durations_[q1], durations_[q2], durations_[q3], durations_[p95], durations_[p99],
+               durations_[p9999], durations_.back());
+    }
+
+  private:
+    std::chrono::steady_clock::time_point operation_start_;
+    std::vector<long long> durations_;
+};
+
+int main(int argc, char** argv) {
+    if (argc < 3) {
+        fprintf(stderr, "Usage: %s FILE OPERATION [BUFFER] [OPTIONS]\n", argv[0]);
+        return 1;
+    }
+
+    if (strcmp(argv[2], "interesting") != 0 && argc < 4) {
+        fprintf(stderr, "Operations other than 'interesting' require a BUFFER argument\n");
+        return 1;
+    }
+
+    int recorded_messages_fd = open(argv[1], O_RDONLY);
+    if (recorded_messages_fd == -1) {
+        fprintf(stderr, "Couldn't open input file\n");
+        return 1;
+    }
+    struct stat fd_stat;
+    if (fstat(recorded_messages_fd, &fd_stat) != 0) {
+        fprintf(stderr, "Couldn't fstat input file\n");
+        return 1;
+    }
+    auto recorded_messages = MappedFile::FromFd(recorded_messages_fd, 0,
+                                                static_cast<size_t>(fd_stat.st_size), PROT_READ);
+    if (recorded_messages == nullptr) {
+        fprintf(stderr, "Couldn't mmap input file\n");
+        return 1;
+    }
+
+    // LogStatistics typically uses 'now()' to initialize its log range state, but this doesn't work
+    // when replaying older logs, so we instead give it the timestamp from the first log.
+    log_time first_log_timestamp = GetFirstTimeStamp(*recorded_messages);
+
+    std::unique_ptr<Operation> operation;
+    if (!strcmp(argv[2], "interesting")) {
+        operation.reset(new PrintInteresting(first_log_timestamp));
+    } else if (!strcmp(argv[2], "memory_usage")) {
+        operation.reset(new PrintMemory(first_log_timestamp, argv[3]));
+    } else if (!strcmp(argv[2], "latency")) {
+        operation.reset(new PrintLatency(first_log_timestamp, argv[3]));
+    } else if (!strcmp(argv[2], "print_logs")) {
+        operation.reset(new PrintLogs(first_log_timestamp, argv[3], argc > 4 ? argv[4] : nullptr,
+                                      argc > 5 ? argv[5] : nullptr));
+    } else if (!strcmp(argv[2], "nothing")) {
+        operation.reset(new SingleBufferOperation(first_log_timestamp, argv[3]));
+    } else {
+        fprintf(stderr, "unknown operation '%s'\n", argv[2]);
+        return 1;
+    }
+
+    // LogBuffer::Log() won't log without this on host.
+    __android_log_set_minimum_priority(ANDROID_LOG_VERBOSE);
+    // But we still want to suppress messages <= error to not interrupt the rest of the output.
+    __android_log_set_logger([](const struct __android_log_message* log_message) {
+        if (log_message->priority < ANDROID_LOG_ERROR) {
+            return;
+        }
+        __android_log_stderr_logger(log_message);
+    });
+
+    operation->Begin();
+
+    uint64_t read_position = 0;
+    while (read_position + sizeof(RecordedLogMessage) < recorded_messages->size()) {
+        auto* meta =
+                reinterpret_cast<RecordedLogMessage*>(recorded_messages->data() + read_position);
+        if (read_position + sizeof(RecordedLogMessage) + meta->msg_len >=
+            recorded_messages->size()) {
+            break;
+        }
+        char* msg = recorded_messages->data() + read_position + sizeof(RecordedLogMessage);
+        read_position += sizeof(RecordedLogMessage) + meta->msg_len;
+
+        operation->Log(*meta, msg);
+    }
+
+    operation->End();
+
+    return 0;
+}
diff --git a/trusty/trusty-test.mk b/trusty/trusty-test.mk
new file mode 100644
index 0000000..fd353d1
--- /dev/null
+++ b/trusty/trusty-test.mk
@@ -0,0 +1,16 @@
+# Copyright (C) 2020 The Android Open-Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+PRODUCT_PACKAGES += \
+	spiproxyd \
diff --git a/trusty/utils/spiproxyd/Android.bp b/trusty/utils/spiproxyd/Android.bp
new file mode 100644
index 0000000..c1d0987
--- /dev/null
+++ b/trusty/utils/spiproxyd/Android.bp
@@ -0,0 +1,36 @@
+// Copyright (C) 2020 The Android Open-Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+cc_binary {
+    name: "spiproxyd",
+    vendor: true,
+
+    srcs: [
+        "main.c",
+    ],
+
+    shared_libs: [
+        "liblog",
+        "libtrusty",
+    ],
+
+    init_rc: [
+        "proxy.rc",
+    ],
+
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+}
diff --git a/trusty/utils/spiproxyd/main.c b/trusty/utils/spiproxyd/main.c
new file mode 100644
index 0000000..c10866b
--- /dev/null
+++ b/trusty/utils/spiproxyd/main.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "spiproxyd"
+
+#include <assert.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <log/log.h>
+#include <stdlib.h>
+#include <string.h>
+#include <trusty/tipc.h>
+#include <unistd.h>
+
+int handle_msg(int trusty_dev_fd, int spi_dev_fd) {
+    int rc;
+    uint8_t msg_buf[4096];
+    size_t msg_len;
+
+    /* read request from SPI Trusty app */
+    rc = read(trusty_dev_fd, &msg_buf, sizeof(msg_buf));
+    if (rc < 0) {
+        ALOGE("failed (%d) to read request from TA\n", rc);
+        return rc;
+    }
+    msg_len = rc;
+
+    /* forward request to SPI host device */
+    rc = write(spi_dev_fd, &msg_buf, msg_len);
+    if (rc < 0 || (size_t)rc != msg_len) {
+        ALOGE("failed (%d) to forward request to host\n", rc);
+        return rc < 0 ? rc : -1;
+    }
+
+    /* read response from SPI host device */
+    rc = read(spi_dev_fd, &msg_buf, sizeof(msg_buf));
+    if (rc < 0) {
+        ALOGE("failed (%d) to read response from host\n", rc);
+        return rc;
+    }
+    msg_len = rc;
+
+    /* forward response to SPI Trusty app */
+    rc = write(trusty_dev_fd, &msg_buf, msg_len);
+    if (rc < 0 || (size_t)rc != msg_len) {
+        ALOGE("failed (%d) to forward response to TA\n", rc);
+        return rc < 0 ? rc : -1;
+    }
+
+    return 0;
+}
+
+int event_loop(int trusty_dev_fd, int spi_dev_fd) {
+    while (true) {
+        int rc = handle_msg(trusty_dev_fd, spi_dev_fd);
+        if (rc < 0) {
+            ALOGE("exiting event loop\n");
+            return EXIT_FAILURE;
+        }
+    }
+}
+
+static void show_usage() {
+    ALOGE("usage: spiproxyd -t TRUSTY_DEVICE -s SPI_DEVICE -p SPI_PROXY_PORT\n");
+}
+
+static void parse_args(int argc, char* argv[], const char** trusty_dev_name,
+                       const char** spi_dev_name, const char** spi_proxy_port) {
+    int opt;
+    while ((opt = getopt(argc, argv, "ht:s:p:")) != -1) {
+        switch (opt) {
+            case 'h':
+                show_usage();
+                exit(EXIT_SUCCESS);
+                break;
+            case 't':
+                *trusty_dev_name = strdup(optarg);
+                break;
+            case 's':
+                *spi_dev_name = strdup(optarg);
+                break;
+            case 'p':
+                *spi_proxy_port = strdup(optarg);
+                break;
+            default:
+                show_usage();
+                exit(EXIT_FAILURE);
+                break;
+        }
+    }
+
+    if (!*trusty_dev_name || !*spi_dev_name || !*spi_proxy_port) {
+        show_usage();
+        exit(EXIT_FAILURE);
+    }
+}
+
+int main(int argc, char* argv[]) {
+    int rc;
+    const char* trusty_dev_name = NULL;
+    const char* spi_dev_name = NULL;
+    const char* spi_proxy_port = NULL;
+    int trusty_dev_fd;
+    int spi_dev_fd;
+
+    parse_args(argc, argv, &trusty_dev_name, &spi_dev_name, &spi_proxy_port);
+
+    rc = tipc_connect(trusty_dev_name, spi_proxy_port);
+    if (rc < 0) {
+        ALOGE("failed (%d) to connect to SPI proxy port\n", rc);
+        return rc;
+    }
+    trusty_dev_fd = rc;
+
+    rc = open(spi_dev_name, O_RDWR, 0);
+    if (rc < 0) {
+        ALOGE("failed (%d) to open SPI device\n", rc);
+        return rc;
+    }
+    spi_dev_fd = rc;
+
+    return event_loop(trusty_dev_fd, spi_dev_fd);
+}
diff --git a/trusty/utils/spiproxyd/proxy.rc b/trusty/utils/spiproxyd/proxy.rc
new file mode 100644
index 0000000..7d63e6a
--- /dev/null
+++ b/trusty/utils/spiproxyd/proxy.rc
@@ -0,0 +1,20 @@
+# Copyright (C) 2020 The Android Open-Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+service spiproxyd /vendor/bin/spiproxyd -t /dev/trusty-ipc-dev0 \
+        -s /dev/vport3p2 -p com.android.trusty.spi.proxy
+    class main
+    user system
+    group system
+    oneshot