Merge "simpleperf: Suppress kernel module read warnings" into main

3 files changed, 18 insertions, 6 deletions

diff --git a/simpleperf/dso.cpp b/simpleperf/dso.cpp
index 607bf7d8..1380ada9 100644
--- a/simpleperf/dso.cpp
+++ b/simpleperf/dso.cpp
@@ -875,8 +875,8 @@ class KernelModuleDso : public Dso {
     if (elf) {
       status = elf->ParseSymbols(symbol_callback);
     }
-    ReportReadElfSymbolResult(status, path_, GetDebugFilePath(),
-                              symbols_.empty() ? android::base::WARNING : android::base::DEBUG);
+    // Don't warn when a kernel module is missing. As a backup, we read symbols from /proc/kallsyms.
+    ReportReadElfSymbolResult(status, path_, GetDebugFilePath(), android::base::DEBUG);
     SortAndFixSymbols(symbols);
     return symbols;
   }
@@ -897,6 +897,10 @@ class KernelModuleDso : public Dso {
     // and its vaddr_in_file from the kernel module file. Then other symbols in .text section can
     // be mapped in the same way. Below we use the second method.
 
+    if (!IsRegularFile(GetDebugFilePath())) {
+      return;
+    }
+
     // 1. Select a module symbol in /proc/kallsyms.
     kernel_dso_->LoadSymbols();
     const auto& kernel_symbols = kernel_dso_->GetSymbols();
diff --git a/simpleperf/dso_test.cpp b/simpleperf/dso_test.cpp
index f5280d32..f9199e41 100644
--- a/simpleperf/dso_test.cpp
+++ b/simpleperf/dso_test.cpp
@@ -294,8 +294,9 @@ TEST(dso, kernel_module_CalculateMinVaddr) {
   ASSERT_TRUE(kernel_dso);
   const uint64_t module_memory_start = 0xffffffa9bc790000ULL;
   const uint64_t module_memory_size = 0x8d7000ULL;
+  TemporaryFile tmpfile;
   auto module_dso =
-      Dso::CreateKernelModuleDso("fake_module.ko", module_memory_start,
+      Dso::CreateKernelModuleDso(tmpfile.path, module_memory_start,
                                  module_memory_start + module_memory_size, kernel_dso.get());
   ASSERT_TRUE(module_dso);
 
diff --git a/simpleperf/environment.cpp b/simpleperf/environment.cpp
index 88587dc3..55074d8a 100644
--- a/simpleperf/environment.cpp
+++ b/simpleperf/environment.cpp
@@ -75,6 +75,9 @@ std::vector<int> GetOnlineCpus() {
 
 static void GetAllModuleFiles(const std::string& path,
                               std::unordered_map<std::string, std::string>* module_file_map) {
+  if (!IsDir(path)) {
+    return;
+  }
   for (const auto& name : GetEntriesInDir(path)) {
     std::string entry_path = path + "/" + name;
     if (IsRegularFile(entry_path) && android::base::EndsWith(name, ".ko")) {
@@ -94,9 +97,13 @@ static std::vector<KernelMmap> GetModulesInUse() {
   }
   std::unordered_map<std::string, std::string> module_file_map;
 #if defined(__ANDROID__)
-  // Search directories listed in "File locations" section in
-  // https://source.android.com/devices/architecture/kernel/modular-kernels.
-  for (const auto& path : {"/vendor/lib/modules", "/odm/lib/modules", "/lib/modules"}) {
+  // On Android, kernel modules are stored in /system/lib/modules, /vendor/lib/modules,
+  // /odm/lib/modules.
+  // See https://source.android.com/docs/core/architecture/partitions/gki-partitions and
+  // https://source.android.com/docs/core/architecture/partitions/vendor-odm-dlkm-partition.
+  // They can also be stored in vendor_kernel_ramdisk.img, which isn't accessible from userspace.
+  // See https://source.android.com/docs/core/architecture/kernel/kernel-module-support.
+  for (const auto& path : {"/system/lib/modules", "/vendor/lib/modules", "/odm/lib/modules"}) {
     GetAllModuleFiles(path, &module_file_map);
   }
 #else