diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index d9fae52..5167481 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -116,14 +116,21 @@
         "libdebuggerd",
         "libbacktrace",
         "libunwindstack",
-        "libdexfile",
+        "libdexfile",  // libunwindstack dependency
+        "libdexfile_external",  // libunwindstack dependency
+        "libdexfile_support",  // libunwindstack dependency
         "liblzma",
         "libcutils",
     ],
     target: {
         recovery: {
             cflags: ["-DNO_LIBDEXFILE_SUPPORT"],
-            exclude_static_libs: ["libdexfile"],
+            exclude_static_libs: [
+                "libartbase",
+                "libdexfile",
+                "libdexfile_external",
+                "libdexfile_support",
+            ],
         },
     },
 
@@ -170,12 +177,22 @@
 
     static_libs: [
         "libbacktrace",
+        "libdexfile_external",  // libunwindstack dependency
+        "libdexfile_support",  // libunwindstack dependency
         "libunwindstack",
         "liblzma",
         "libbase",
         "libcutils",
         "liblog",
     ],
+    target: {
+        recovery: {
+            exclude_static_libs: [
+                "libdexfile_external",
+                "libdexfile_support",
+            ],
+        },
+    },
 }
 
 cc_test {
@@ -216,6 +233,8 @@
 
     static_libs: [
         "libdebuggerd",
+        "libdexfile_external",  // libunwindstack dependency
+        "libdexfile_support",  // libunwindstack dependency
         "libunwindstack",
     ],
 
diff --git a/fs_mgr/fs_mgr_fstab.cpp b/fs_mgr/fs_mgr_fstab.cpp
index d3cd459..bd9d675 100644
--- a/fs_mgr/fs_mgr_fstab.cpp
+++ b/fs_mgr/fs_mgr_fstab.cpp
@@ -59,7 +59,7 @@
 
 struct flag_list {
     const char *name;
-    unsigned int flag;
+    uint64_t flag;
 };
 
 static struct flag_list mount_flags[] = {
@@ -116,6 +116,7 @@
         {"logical", MF_LOGICAL},
         {"checkpoint=block", MF_CHECKPOINT_BLK},
         {"checkpoint=fs", MF_CHECKPOINT_FS},
+        {"slotselect_other", MF_SLOTSELECT_OTHER},
         {0, 0},
 };
 
@@ -207,11 +208,9 @@
     return false;
 }
 
-static int parse_flags(char *flags, struct flag_list *fl,
-                       struct fs_mgr_flag_values *flag_vals,
-                       char *fs_options, int fs_options_len)
-{
-    int f = 0;
+static uint64_t parse_flags(char* flags, struct flag_list* fl, struct fs_mgr_flag_values* flag_vals,
+                            char* fs_options, int fs_options_len) {
+    uint64_t f = 0;
     int i;
     char *p;
     char *savep;
diff --git a/fs_mgr/fs_mgr_priv.h b/fs_mgr/fs_mgr_priv.h
index 072da97..7d1159b 100644
--- a/fs_mgr/fs_mgr_priv.h
+++ b/fs_mgr/fs_mgr_priv.h
@@ -120,6 +120,8 @@
 #define MF_CHECKPOINT_FS  0x40000000
 #define MF_FIRST_STAGE_MOUNT \
                           0x80000000
+#define MF_SLOTSELECT_OTHER  \
+                         0x100000000
 // clang-format on
 
 #define DM_BUF_SIZE 4096
diff --git a/fs_mgr/fs_mgr_slotselect.cpp b/fs_mgr/fs_mgr_slotselect.cpp
index efc29bd..3cb718c 100644
--- a/fs_mgr/fs_mgr_slotselect.cpp
+++ b/fs_mgr/fs_mgr_slotselect.cpp
@@ -21,6 +21,19 @@
 #include "fs_mgr.h"
 #include "fs_mgr_priv.h"
 
+// https://source.android.com/devices/tech/ota/ab/ab_implement#partitions
+// All partitions that are A/B-ed should be named as follows (slots are always
+// named a, b, etc.): boot_a, boot_b, system_a, system_b, vendor_a, vendor_b.
+static std::string other_suffix(const std::string& slot_suffix) {
+    if (slot_suffix == "_a") {
+        return "_b";
+    }
+    if (slot_suffix == "_b") {
+        return "_a";
+    }
+    return "";
+}
+
 // Returns "_a" or "_b" based on androidboot.slot_suffix in kernel cmdline, or an empty string
 // if that parameter does not exist.
 std::string fs_mgr_get_slot_suffix() {
@@ -35,7 +48,7 @@
     std::string ab_suffix;
 
     for (auto& entry : *fstab) {
-        if (!entry.fs_mgr_flags.slot_select) {
+        if (!entry.fs_mgr_flags.slot_select && !entry.fs_mgr_flags.slot_select_other) {
             continue;
         }
 
@@ -45,8 +58,10 @@
             if (ab_suffix.empty()) return false;
         }
 
-        entry.blk_device = entry.blk_device + ab_suffix;
-        entry.logical_partition_name = entry.logical_partition_name + ab_suffix;
+        const auto& update_suffix =
+                entry.fs_mgr_flags.slot_select ? ab_suffix : other_suffix(ab_suffix);
+        entry.blk_device = entry.blk_device + update_suffix;
+        entry.logical_partition_name = entry.logical_partition_name + update_suffix;
     }
     return true;
 }
diff --git a/fs_mgr/include_fstab/fstab/fstab.h b/fs_mgr/include_fstab/fstab/fstab.h
index d9a5e0a..0997254 100644
--- a/fs_mgr/include_fstab/fstab/fstab.h
+++ b/fs_mgr/include_fstab/fstab/fstab.h
@@ -43,7 +43,7 @@
     char* fs_type;
     unsigned long flags;
     char* fs_options;
-    int fs_mgr_flags;
+    uint64_t fs_mgr_flags;
     char* key_loc;
     char* key_dir;
     char* verity_loc;
@@ -123,8 +123,9 @@
     // TODO: Remove this union once fstab_rec is deprecated. It only serves as a
     // convenient way to convert between fstab_rec::fs_mgr_flags and these bools.
     union {
-        int val;
+        uint64_t val;
         struct {
+            // bit 0
             bool wait : 1;
             bool check : 1;
             bool crypt : 1;
@@ -133,6 +134,8 @@
             bool length : 1;
             bool recovery_only : 1;
             bool swap_prio : 1;
+
+            // bit 8
             bool zram_size : 1;
             bool verify : 1;
             bool force_crypt : 1;
@@ -142,6 +145,8 @@
             bool file_encryption : 1;
             bool formattable : 1;
             bool slot_select : 1;
+
+            // bit 16
             bool force_fde_or_fbe : 1;
             bool late_mount : 1;
             bool no_fail : 1;
@@ -150,6 +155,8 @@
             bool reserved_size : 1;
             bool quota : 1;
             bool erase_blk_size : 1;
+
+            // bit 24
             bool logical_blk_size : 1;
             bool avb : 1;
             bool key_directory : 1;
@@ -158,6 +165,9 @@
             bool checkpoint_blk : 1;
             bool checkpoint_fs : 1;
             bool first_stage_mount : 1;
+
+            // bit 32
+            bool slot_select_other : 1;
         };
     } fs_mgr_flags;
 
diff --git a/fs_mgr/tests/adb-remount-test.sh b/fs_mgr/tests/adb-remount-test.sh
index fde82b4..5957e30 100755
--- a/fs_mgr/tests/adb-remount-test.sh
+++ b/fs_mgr/tests/adb-remount-test.sh
@@ -36,14 +36,25 @@
 
 Returns: true if device is in fastboot mode" ]
 inFastboot() {
-  fastboot devices | grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null
+  fastboot devices |
+    if [ -n "${ANDROID_SERIAL}" ]; then
+      grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null
+    else
+      wc -l | grep '^1$' >/dev/null
+    fi
 }
 
 [ "USAGE: inAdb
 
 Returns: true if device is in adb mode" ]
 inAdb() {
-  adb devices | grep -v 'List of devices attached' | grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null
+  adb devices |
+    grep -v 'List of devices attached' |
+    if [ -n "${ANDROID_SERIAL}" ]; then
+      grep "^${ANDROID_SERIAL}[${SPACE}${TAB}]" > /dev/null
+    else
+      wc -l | grep '^1$' >/dev/null
+    fi
 }
 
 [ "USAGE: adb_sh <commands> </dev/stdin >/dev/stdout 2>/dev/stderr
@@ -277,8 +288,13 @@
   echo "${ORANGE}[  WARNING ]${NORMAL} device not in adb mode ... waiting 2 minutes"
   adb_wait 2m
 fi
-inAdb || die "device not in adb mode"
+inAdb || die "specified device not in adb mode"
 isDebuggable || die "device not a debug build"
+enforcing=true
+if ! adb_su getenforce </dev/null | grep 'Enforcing' >/dev/null; then
+  echo "${ORANGE}[  WARNING ]${NORMAL} device does not have sepolicy in enforcing mode"
+  enforcing=false
+fi
 
 # Do something
 
@@ -524,9 +540,11 @@
   die "re-read system hello after reboot"
 check_eq "${A}" "${B}" system after reboot
 # Only root can read vendor if sepolicy permissions are as expected
-B="`adb_cat /vendor/hello`" &&
-  die "re-read vendor hello after reboot w/o root"
-check_eq "cat: /vendor/hello: Permission denied" "${B}" vendor after reboot w/o root
+if ${enforcing}; then
+  B="`adb_cat /vendor/hello`" &&
+    die "re-read vendor hello after reboot w/o root"
+  check_eq "cat: /vendor/hello: Permission denied" "${B}" vendor after reboot w/o root
+fi
 adb_root &&
   B="`adb_cat /vendor/hello`" ||
   die "re-read vendor hello after reboot"
diff --git a/libunwindstack/Android.bp b/libunwindstack/Android.bp
index 4e0470e..89d4fc0 100644
--- a/libunwindstack/Android.bp
+++ b/libunwindstack/Android.bp
@@ -94,7 +94,10 @@
                 "DexFile.cpp",
                 "DexFiles.cpp",
             ],
-            exclude_shared_libs: ["libdexfile"],
+            exclude_shared_libs: [
+                "libdexfile_external",
+                "libdexfile_support",
+            ],
         },
         recovery: {
             cflags: ["-DNO_LIBDEXFILE_SUPPORT"],
@@ -102,7 +105,10 @@
                 "DexFile.cpp",
                 "DexFiles.cpp",
             ],
-            exclude_shared_libs: ["libdexfile"],
+            exclude_shared_libs: [
+                "libdexfile_external",
+                "libdexfile_support",
+            ],
         },
     },
 
@@ -127,7 +133,8 @@
 
     shared_libs: [
         "libbase",
-        "libdexfile",
+        "libdexfile_external",
+        "libdexfile_support",
         "liblog",
         "liblzma",
     ],
@@ -215,6 +222,7 @@
         "liblzma",
         "libunwindstack",
         "libdexfile",
+        "libdexfile_support",
     ],
 
     static_libs: [
diff --git a/libunwindstack/DexFile.cpp b/libunwindstack/DexFile.cpp
index 8ec560c..9b0b232 100644
--- a/libunwindstack/DexFile.cpp
+++ b/libunwindstack/DexFile.cpp
@@ -23,13 +23,7 @@
 #include <memory>
 
 #include <android-base/unique_fd.h>
-
-#include <dex/class_accessor-inl.h>
-#include <dex/code_item_accessors-inl.h>
-#include <dex/compact_dex_file.h>
-#include <dex/dex_file-inl.h>
-#include <dex/dex_file_loader.h>
-#include <dex/standard_dex_file.h>
+#include <art_api/ext_dex_file.h>
 
 #include <unwindstack/MapInfo.h>
 #include <unwindstack/Memory.h>
@@ -38,169 +32,71 @@
 
 namespace unwindstack {
 
-DexFile* DexFile::Create(uint64_t dex_file_offset_in_memory, Memory* memory, MapInfo* info) {
+std::unique_ptr<DexFile> DexFile::Create(uint64_t dex_file_offset_in_memory, Memory* memory,
+                                         MapInfo* info) {
   if (!info->name.empty()) {
-    std::unique_ptr<DexFileFromFile> dex_file(new DexFileFromFile);
-    if (dex_file->Open(dex_file_offset_in_memory - info->start + info->offset, info->name)) {
-      return dex_file.release();
+    std::unique_ptr<DexFile> dex_file =
+        DexFileFromFile::Create(dex_file_offset_in_memory - info->start + info->offset, info->name);
+    if (dex_file) {
+      return dex_file;
     }
   }
-
-  std::unique_ptr<DexFileFromMemory> dex_file(new DexFileFromMemory);
-  if (dex_file->Open(dex_file_offset_in_memory, memory)) {
-    return dex_file.release();
-  }
-  return nullptr;
-}
-
-DexFileFromFile::~DexFileFromFile() {
-  if (size_ != 0) {
-    munmap(mapped_memory_, size_);
-  }
+  return DexFileFromMemory::Create(dex_file_offset_in_memory, memory, info->name);
 }
 
 bool DexFile::GetMethodInformation(uint64_t dex_offset, std::string* method_name,
                                    uint64_t* method_offset) {
-  if (dex_file_ == nullptr) {
+  art_api::dex::MethodInfo method_info = GetMethodInfoForOffset(dex_offset);
+  if (method_info.offset == 0) {
     return false;
   }
-
-  if (!dex_file_->IsInDataSection(dex_file_->Begin() + dex_offset)) {
-    return false;  // The DEX offset is not within the bytecode of this dex file.
-  }
-
-  if (dex_file_->IsCompactDexFile()) {
-    // The data section of compact dex files might be shared.
-    // Check the subrange unique to this compact dex.
-    const auto& cdex_header = dex_file_->AsCompactDexFile()->GetHeader();
-    uint32_t begin = cdex_header.data_off_ + cdex_header.OwnedDataBegin();
-    uint32_t end = cdex_header.data_off_ + cdex_header.OwnedDataEnd();
-    if (dex_offset < begin || dex_offset >= end) {
-      return false;  // The DEX offset is not within the bytecode of this dex file.
-    }
-  }
-
-  // The method data is cached in a std::map indexed by method end offset and
-  // contains the start offset and the method member index.
-  // Only cache the method data as it is searched. Do not read the entire
-  // set of method data into the cache at once.
-  // This is done because many unwinds only find a single frame with dex file
-  // info, so reading the entire method data is wasteful. However, still cache
-  // the data so that anything doing multiple unwinds will have this data
-  // cached for future use.
-
-  // First look in the method cache.
-  auto entry = method_cache_.upper_bound(dex_offset);
-  if (entry != method_cache_.end() && dex_offset >= entry->second.first) {
-    *method_name = dex_file_->PrettyMethod(entry->second.second, false);
-    *method_offset = dex_offset - entry->second.first;
-    return true;
-  }
-
-  // Check the methods we haven't cached.
-  for (; class_def_index_ < dex_file_->NumClassDefs(); class_def_index_++) {
-    art::ClassAccessor accessor(*dex_file_, dex_file_->GetClassDef(class_def_index_));
-
-    for (const art::ClassAccessor::Method& method : accessor.GetMethods()) {
-      art::CodeItemInstructionAccessor code = method.GetInstructions();
-      if (!code.HasCodeItem()) {
-        continue;
-      }
-      uint32_t offset = reinterpret_cast<const uint8_t*>(code.Insns()) - dex_file_->Begin();
-      uint32_t offset_end = offset + code.InsnsSizeInBytes();
-      uint32_t member_index = method.GetIndex();
-      method_cache_[offset_end] = std::make_pair(offset, member_index);
-      if (offset <= dex_offset && dex_offset < offset_end) {
-        *method_name = dex_file_->PrettyMethod(member_index, false);
-        *method_offset = dex_offset - offset;
-        return true;
-      }
-    }
-  }
-  return false;
+  *method_name = method_info.name;
+  *method_offset = dex_offset - method_info.offset;
+  return true;
 }
 
-bool DexFileFromFile::Open(uint64_t dex_file_offset_in_file, const std::string& file) {
+std::unique_ptr<DexFileFromFile> DexFileFromFile::Create(uint64_t dex_file_offset_in_file,
+                                                         const std::string& file) {
   android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(file.c_str(), O_RDONLY | O_CLOEXEC)));
   if (fd == -1) {
-    return false;
-  }
-  struct stat buf;
-  if (fstat(fd, &buf) == -1) {
-    return false;
-  }
-  uint64_t length;
-  if (buf.st_size < 0 ||
-      __builtin_add_overflow(dex_file_offset_in_file, sizeof(art::DexFile::Header), &length) ||
-      static_cast<uint64_t>(buf.st_size) < length) {
-    return false;
+    return nullptr;
   }
 
-  mapped_memory_ = mmap(nullptr, buf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-  if (mapped_memory_ == MAP_FAILED) {
-    return false;
-  }
-  size_ = buf.st_size;
-
-  uint8_t* memory = reinterpret_cast<uint8_t*>(mapped_memory_);
-
-  art::DexFile::Header* header =
-      reinterpret_cast<art::DexFile::Header*>(&memory[dex_file_offset_in_file]);
-  if (!art::StandardDexFile::IsMagicValid(header->magic_) &&
-      !art::CompactDexFile::IsMagicValid(header->magic_)) {
-    return false;
-  }
-
-  if (__builtin_add_overflow(dex_file_offset_in_file, header->file_size_, &length) ||
-      static_cast<uint64_t>(buf.st_size) < length) {
-    return false;
-  }
-
-  art::DexFileLoader loader;
   std::string error_msg;
-  auto dex = loader.Open(&memory[dex_file_offset_in_file], header->file_size_, "", 0, nullptr,
-                         false, false, &error_msg);
-  dex_file_.reset(dex.release());
-  return dex_file_ != nullptr;
+  std::unique_ptr<art_api::dex::DexFile> art_dex_file =
+      OpenFromFd(fd, dex_file_offset_in_file, file, &error_msg);
+  if (art_dex_file == nullptr) {
+    return nullptr;
+  }
+
+  return std::unique_ptr<DexFileFromFile>(new DexFileFromFile(std::move(*art_dex_file.release())));
 }
 
-bool DexFileFromMemory::Open(uint64_t dex_file_offset_in_memory, Memory* memory) {
-  memory_.resize(sizeof(art::DexFile::Header));
-  if (!memory->ReadFully(dex_file_offset_in_memory, memory_.data(), memory_.size())) {
-    return false;
-  }
+std::unique_ptr<DexFileFromMemory> DexFileFromMemory::Create(uint64_t dex_file_offset_in_memory,
+                                                             Memory* memory,
+                                                             const std::string& name) {
+  std::vector<uint8_t> backing_memory;
 
-  art::DexFile::Header* header = reinterpret_cast<art::DexFile::Header*>(memory_.data());
-  uint32_t file_size = header->file_size_;
-  if (art::CompactDexFile::IsMagicValid(header->magic_)) {
-    // Compact dex file store data section separately so that it can be shared.
-    // Therefore we need to extend the read memory range to include it.
-    // TODO: This might be wasteful as we might read data in between as well.
-    //       In practice, this should be fine, as such sharing only happens on disk.
-    uint32_t computed_file_size;
-    if (__builtin_add_overflow(header->data_off_, header->data_size_, &computed_file_size)) {
-      return false;
+  for (size_t size = 0;;) {
+    std::string error_msg;
+    std::unique_ptr<art_api::dex::DexFile> art_dex_file =
+        OpenFromMemory(backing_memory.data(), &size, name, &error_msg);
+
+    if (art_dex_file != nullptr) {
+      return std::unique_ptr<DexFileFromMemory>(
+          new DexFileFromMemory(std::move(*art_dex_file.release()), std::move(backing_memory)));
     }
-    if (computed_file_size > file_size) {
-      file_size = computed_file_size;
+
+    if (!error_msg.empty()) {
+      return nullptr;
     }
-  } else if (!art::StandardDexFile::IsMagicValid(header->magic_)) {
-    return false;
+
+    backing_memory.resize(size);
+    if (!memory->ReadFully(dex_file_offset_in_memory, backing_memory.data(),
+                           backing_memory.size())) {
+      return nullptr;
+    }
   }
-
-  memory_.resize(file_size);
-  if (!memory->ReadFully(dex_file_offset_in_memory, memory_.data(), memory_.size())) {
-    return false;
-  }
-
-  header = reinterpret_cast<art::DexFile::Header*>(memory_.data());
-
-  art::DexFileLoader loader;
-  std::string error_msg;
-  auto dex =
-      loader.Open(memory_.data(), header->file_size_, "", 0, nullptr, false, false, &error_msg);
-  dex_file_.reset(dex.release());
-  return dex_file_ != nullptr;
 }
 
 }  // namespace unwindstack
diff --git a/libunwindstack/DexFile.h b/libunwindstack/DexFile.h
index c123158..5797dee 100644
--- a/libunwindstack/DexFile.h
+++ b/libunwindstack/DexFile.h
@@ -25,48 +25,41 @@
 #include <utility>
 #include <vector>
 
-#include <dex/dex_file-inl.h>
+#include <art_api/ext_dex_file.h>
 
 namespace unwindstack {
 
-class DexFile {
+class DexFile : protected art_api::dex::DexFile {
  public:
-  DexFile() = default;
   virtual ~DexFile() = default;
 
   bool GetMethodInformation(uint64_t dex_offset, std::string* method_name, uint64_t* method_offset);
 
-  static DexFile* Create(uint64_t dex_file_offset_in_memory, Memory* memory, MapInfo* info);
+  static std::unique_ptr<DexFile> Create(uint64_t dex_file_offset_in_memory, Memory* memory,
+                                         MapInfo* info);
 
  protected:
-  void Init();
-
-  std::unique_ptr<const art::DexFile> dex_file_;
-  std::map<uint32_t, std::pair<uint64_t, uint32_t>> method_cache_;  // dex offset to method index.
-
-  uint32_t class_def_index_ = 0;
+  DexFile(art_api::dex::DexFile&& art_dex_file) : art_api::dex::DexFile(std::move(art_dex_file)) {}
 };
 
 class DexFileFromFile : public DexFile {
  public:
-  DexFileFromFile() = default;
-  virtual ~DexFileFromFile();
-
-  bool Open(uint64_t dex_file_offset_in_file, const std::string& name);
+  static std::unique_ptr<DexFileFromFile> Create(uint64_t dex_file_offset_in_file,
+                                                 const std::string& file);
 
  private:
-  void* mapped_memory_ = nullptr;
-  size_t size_ = 0;
+  DexFileFromFile(art_api::dex::DexFile&& art_dex_file) : DexFile(std::move(art_dex_file)) {}
 };
 
 class DexFileFromMemory : public DexFile {
  public:
-  DexFileFromMemory() = default;
-  virtual ~DexFileFromMemory() = default;
-
-  bool Open(uint64_t dex_file_offset_in_memory, Memory* memory);
+  static std::unique_ptr<DexFileFromMemory> Create(uint64_t dex_file_offset_in_memory,
+                                                   Memory* memory, const std::string& name);
 
  private:
+  DexFileFromMemory(art_api::dex::DexFile&& art_dex_file, std::vector<uint8_t>&& memory)
+      : DexFile(std::move(art_dex_file)), memory_(std::move(memory)) {}
+
   std::vector<uint8_t> memory_;
 };
 
diff --git a/libunwindstack/DexFiles.cpp b/libunwindstack/DexFiles.cpp
index 451a0b9..63a77e5 100644
--- a/libunwindstack/DexFiles.cpp
+++ b/libunwindstack/DexFiles.cpp
@@ -48,11 +48,7 @@
 DexFiles::DexFiles(std::shared_ptr<Memory>& memory, std::vector<std::string>& search_libs)
     : Global(memory, search_libs) {}
 
-DexFiles::~DexFiles() {
-  for (auto& entry : files_) {
-    delete entry.second;
-  }
-}
+DexFiles::~DexFiles() {}
 
 void DexFiles::ProcessArch() {
   switch (arch()) {
@@ -137,10 +133,11 @@
   DexFile* dex_file;
   auto entry = files_.find(dex_file_offset);
   if (entry == files_.end()) {
-    dex_file = DexFile::Create(dex_file_offset, memory_.get(), info);
-    files_[dex_file_offset] = dex_file;
+    std::unique_ptr<DexFile> new_dex_file = DexFile::Create(dex_file_offset, memory_.get(), info);
+    dex_file = new_dex_file.get();
+    files_[dex_file_offset] = std::move(new_dex_file);
   } else {
-    dex_file = entry->second;
+    dex_file = entry->second.get();
   }
   return dex_file;
 }
diff --git a/libunwindstack/include/unwindstack/DexFiles.h b/libunwindstack/include/unwindstack/DexFiles.h
index c202a33..0336173 100644
--- a/libunwindstack/include/unwindstack/DexFiles.h
+++ b/libunwindstack/include/unwindstack/DexFiles.h
@@ -66,7 +66,7 @@
 
   std::mutex lock_;
   bool initialized_ = false;
-  std::unordered_map<uint64_t, DexFile*> files_;
+  std::unordered_map<uint64_t, std::unique_ptr<DexFile>> files_;
 
   uint64_t entry_addr_ = 0;
   uint64_t (DexFiles::*read_entry_ptr_func_)(uint64_t) = nullptr;
diff --git a/libunwindstack/tests/DexFileTest.cpp b/libunwindstack/tests/DexFileTest.cpp
index 95d2176..21ca47b 100644
--- a/libunwindstack/tests/DexFileTest.cpp
+++ b/libunwindstack/tests/DexFileTest.cpp
@@ -21,44 +21,37 @@
 #include <unordered_map>
 
 #include <android-base/file.h>
-
+#include <dex/dex_file.h>
+#include <gtest/gtest.h>
 #include <unwindstack/MapInfo.h>
 #include <unwindstack/Memory.h>
 
-#include <dex/code_item_accessors-inl.h>
-#include <dex/standard_dex_file.h>
-
-#include <gtest/gtest.h>
-
 #include "DexFile.h"
-
 #include "DexFileData.h"
 #include "MemoryFake.h"
 
 namespace unwindstack {
 
 TEST(DexFileTest, from_file_open_non_exist) {
-  DexFileFromFile dex_file;
-  ASSERT_FALSE(dex_file.Open(0, "/file/does/not/exist"));
+  EXPECT_TRUE(DexFileFromFile::Create(0, "/file/does/not/exist") == nullptr);
 }
 
 TEST(DexFileTest, from_file_open_too_small) {
   TemporaryFile tf;
   ASSERT_TRUE(tf.fd != -1);
 
-  ASSERT_EQ(sizeof(art::DexFile::Header) - 2,
+  ASSERT_EQ(sizeof(art::DexFile::Header) - 1,
             static_cast<size_t>(
-                TEMP_FAILURE_RETRY(write(tf.fd, kDexData, sizeof(art::DexFile::Header)) - 2)));
+                TEMP_FAILURE_RETRY(write(tf.fd, kDexData, sizeof(art::DexFile::Header) - 1))));
 
   // Header too small.
-  DexFileFromFile dex_file;
-  ASSERT_FALSE(dex_file.Open(0, tf.path));
+  EXPECT_TRUE(DexFileFromFile::Create(0, tf.path) == nullptr);
 
   // Header correct, file too small.
   ASSERT_EQ(0, lseek(tf.fd, 0, SEEK_SET));
   ASSERT_EQ(sizeof(art::DexFile::Header), static_cast<size_t>(TEMP_FAILURE_RETRY(write(
                                               tf.fd, kDexData, sizeof(art::DexFile::Header)))));
-  ASSERT_FALSE(dex_file.Open(0, tf.path));
+  EXPECT_TRUE(DexFileFromFile::Create(0, tf.path) == nullptr);
 }
 
 TEST(DexFileTest, from_file_open) {
@@ -68,8 +61,7 @@
   ASSERT_EQ(sizeof(kDexData),
             static_cast<size_t>(TEMP_FAILURE_RETRY(write(tf.fd, kDexData, sizeof(kDexData)))));
 
-  DexFileFromFile dex_file;
-  ASSERT_TRUE(dex_file.Open(0, tf.path));
+  EXPECT_TRUE(DexFileFromFile::Create(0, tf.path) != nullptr);
 }
 
 TEST(DexFileTest, from_file_open_non_zero_offset) {
@@ -80,35 +72,31 @@
   ASSERT_EQ(sizeof(kDexData),
             static_cast<size_t>(TEMP_FAILURE_RETRY(write(tf.fd, kDexData, sizeof(kDexData)))));
 
-  DexFileFromFile dex_file;
-  ASSERT_TRUE(dex_file.Open(0x100, tf.path));
+  EXPECT_TRUE(DexFileFromFile::Create(0x100, tf.path) != nullptr);
 }
 
 TEST(DexFileTest, from_memory_fail_too_small_for_header) {
   MemoryFake memory;
 
   memory.SetMemory(0x1000, kDexData, sizeof(art::DexFile::Header) - 1);
-  DexFileFromMemory dex_file;
 
-  ASSERT_FALSE(dex_file.Open(0x1000, &memory));
+  EXPECT_TRUE(DexFileFromMemory::Create(0x1000, &memory, "") == nullptr);
 }
 
 TEST(DexFileTest, from_memory_fail_too_small_for_data) {
   MemoryFake memory;
 
   memory.SetMemory(0x1000, kDexData, sizeof(kDexData) - 2);
-  DexFileFromMemory dex_file;
 
-  ASSERT_FALSE(dex_file.Open(0x1000, &memory));
+  EXPECT_TRUE(DexFileFromMemory::Create(0x1000, &memory, "") == nullptr);
 }
 
 TEST(DexFileTest, from_memory_open) {
   MemoryFake memory;
 
   memory.SetMemory(0x1000, kDexData, sizeof(kDexData));
-  DexFileFromMemory dex_file;
 
-  ASSERT_TRUE(dex_file.Open(0x1000, &memory));
+  EXPECT_TRUE(DexFileFromMemory::Create(0x1000, &memory, "") != nullptr);
 }
 
 TEST(DexFileTest, create_using_file) {
@@ -121,8 +109,7 @@
 
   MemoryFake memory;
   MapInfo info(nullptr, 0, 0x10000, 0, 0x5, tf.path);
-  std::unique_ptr<DexFile> dex_file(DexFile::Create(0x500, &memory, &info));
-  ASSERT_TRUE(dex_file != nullptr);
+  EXPECT_TRUE(DexFile::Create(0x500, &memory, &info) != nullptr);
 }
 
 TEST(DexFileTest, create_using_file_non_zero_start) {
@@ -135,8 +122,7 @@
 
   MemoryFake memory;
   MapInfo info(nullptr, 0x100, 0x10000, 0, 0x5, tf.path);
-  std::unique_ptr<DexFile> dex_file(DexFile::Create(0x600, &memory, &info));
-  ASSERT_TRUE(dex_file != nullptr);
+  EXPECT_TRUE(DexFile::Create(0x600, &memory, &info) != nullptr);
 }
 
 TEST(DexFileTest, create_using_file_non_zero_offset) {
@@ -149,24 +135,21 @@
 
   MemoryFake memory;
   MapInfo info(nullptr, 0x100, 0x10000, 0x200, 0x5, tf.path);
-  std::unique_ptr<DexFile> dex_file(DexFile::Create(0x400, &memory, &info));
-  ASSERT_TRUE(dex_file != nullptr);
+  EXPECT_TRUE(DexFile::Create(0x400, &memory, &info) != nullptr);
 }
 
 TEST(DexFileTest, create_using_memory_empty_file) {
   MemoryFake memory;
   memory.SetMemory(0x4000, kDexData, sizeof(kDexData));
   MapInfo info(nullptr, 0x100, 0x10000, 0x200, 0x5, "");
-  std::unique_ptr<DexFile> dex_file(DexFile::Create(0x4000, &memory, &info));
-  ASSERT_TRUE(dex_file != nullptr);
+  EXPECT_TRUE(DexFile::Create(0x4000, &memory, &info) != nullptr);
 }
 
 TEST(DexFileTest, create_using_memory_file_does_not_exist) {
   MemoryFake memory;
   memory.SetMemory(0x4000, kDexData, sizeof(kDexData));
   MapInfo info(nullptr, 0x100, 0x10000, 0x200, 0x5, "/does/not/exist");
-  std::unique_ptr<DexFile> dex_file(DexFile::Create(0x4000, &memory, &info));
-  ASSERT_TRUE(dex_file != nullptr);
+  EXPECT_TRUE(DexFile::Create(0x4000, &memory, &info) != nullptr);
 }
 
 TEST(DexFileTest, create_using_memory_file_is_malformed) {
@@ -179,22 +162,13 @@
   MemoryFake memory;
   memory.SetMemory(0x4000, kDexData, sizeof(kDexData));
   MapInfo info(nullptr, 0x4000, 0x10000, 0x200, 0x5, "/does/not/exist");
-  std::unique_ptr<DexFile> dex_file(DexFile::Create(0x4000, &memory, &info));
+  std::unique_ptr<DexFile> dex_file = DexFile::Create(0x4000, &memory, &info);
   ASSERT_TRUE(dex_file != nullptr);
 
   // Check it came from memory by clearing memory and verifying it fails.
   memory.Clear();
-  dex_file.reset(DexFile::Create(0x4000, &memory, &info));
-  ASSERT_TRUE(dex_file == nullptr);
-}
-
-TEST(DexFileTest, get_method_not_opened) {
-  std::string method("something");
-  uint64_t method_offset = 100;
-  DexFile dex_file;
-  dex_file.GetMethodInformation(0x100, &method, &method_offset);
-  EXPECT_EQ("something", method);
-  EXPECT_EQ(100U, method_offset);
+  dex_file = DexFile::Create(0x4000, &memory, &info);
+  EXPECT_TRUE(dex_file == nullptr);
 }
 
 TEST(DexFileTest, get_method) {
diff --git a/llkd/libllkd.cpp b/llkd/libllkd.cpp
index 969f26b..267da4a 100644
--- a/llkd/libllkd.cpp
+++ b/llkd/libllkd.cpp
@@ -510,9 +510,7 @@
     return android::base::Trim(content) == string;
 }
 
-void llkPanicKernel(bool dump, pid_t tid, const char* state,
-                    const std::string& message = "") __noreturn;
-void llkPanicKernel(bool dump, pid_t tid, const char* state, const std::string& message) {
+void llkPanicKernel(bool dump, pid_t tid, const char* state, const std::string& message = "") {
     if (!message.empty()) LOG(ERROR) << message;
     auto sysrqTriggerFd = llkFileToWriteFd("/proc/sysrq-trigger");
     if (sysrqTriggerFd < 0) {
@@ -521,6 +519,7 @@
         // The answer to life, the universe and everything
         ::exit(42);
         // NOTREACHED
+        return;
     }
     ::sync();
     if (dump) {
@@ -544,6 +543,13 @@
     llkWriteStringToFile(message + (message.empty() ? "" : "\n") +
                                  "SysRq : Trigger a crash : 'livelock,"s + state + "'\n",
                          "/dev/kmsg");
+    // Because panic is such a serious thing to do, let us
+    // make sure that the tid being inspected still exists!
+    auto piddir = procdir + std::to_string(tid) + "/stat";
+    if (access(piddir.c_str(), F_OK) != 0) {
+        PLOG(WARNING) << piddir;
+        return;
+    }
     android::base::WriteStringToFd("c", sysrqTriggerFd);
     // NOTREACHED
     // DYB
@@ -909,6 +915,7 @@
     ms -= llkCycle;
     auto myPid = ::getpid();
     auto myTid = ::gettid();
+    auto dump = true;
     for (auto dp = llkTopDirectory.read(); dp != nullptr; dp = llkTopDirectory.read()) {
         std::string piddir;
 
@@ -1109,9 +1116,10 @@
             const auto message = state + " "s + llkFormat(procp->count) + " " +
                                  std::to_string(ppid) + "->" + std::to_string(pid) + "->" +
                                  std::to_string(tid) + " " + procp->getComm() + " [panic]";
-            llkPanicKernel(true, tid,
+            llkPanicKernel(dump, tid,
                            (state == 'Z') ? "zombie" : (state == 'D') ? "driver" : "sleeping",
                            message);
+            dump = false;
         }
         LOG(VERBOSE) << "+closedir()";
     }