From f3483ec6a0950b32c29b2ec30f3e256aaee0c279 Mon Sep 17 00:00:00 2001
From: Will McVicker <willmcvicker@google.com>
Date: Wed, 29 Apr 2020 10:11:16 -0700
Subject: [PATCH] first_stage_init: add support to skip module load failures

Extend androidboot.first_stage_console cmdline property to enable
skipping module load failures without stopping at a serial console. This
is useful for GKI development.

Set androidboot.first_stage_console=2 for this behavior.

Bug: 155296582
Test: verify behavior for values 0, 1, and 2
Merged-In: I068c631a22c848e45a421b297b1acae1b3deb3c1
Change-Id: I068c631a22c848e45a421b297b1acae1b3deb3c1
(cherry picked from commit 6c5f82642ba7cd770fde859273b01a8268d75dfc)
---
 init/first_stage_console.cpp | 15 +++++++++++++--
 init/first_stage_console.h   |  9 ++++++++-
 init/first_stage_init.cpp    |  6 +++---
 3 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/init/first_stage_console.cpp b/init/first_stage_console.cpp
index cae53f440..cfa0d99ee 100644
--- a/init/first_stage_console.cpp
+++ b/init/first_stage_console.cpp
@@ -16,6 +16,7 @@
 
 #include "first_stage_console.h"
 
+#include <stdio.h>
 #include <sys/stat.h>
 #include <sys/sysmacros.h>
 #include <sys/types.h>
@@ -87,8 +88,18 @@ void StartConsole() {
     _exit(127);
 }
 
-bool FirstStageConsole(const std::string& cmdline) {
-    return cmdline.find("androidboot.first_stage_console=1") != std::string::npos;
+int FirstStageConsole(const std::string& cmdline) {
+    auto pos = cmdline.find("androidboot.first_stage_console=");
+    if (pos != std::string::npos) {
+        int val = 0;
+        if (sscanf(cmdline.c_str() + pos, "androidboot.first_stage_console=%d", &val) != 1) {
+            return FirstStageConsoleParam::DISABLED;
+        }
+        if (val <= FirstStageConsoleParam::MAX_PARAM_VALUE && val >= 0) {
+            return val;
+        }
+    }
+    return FirstStageConsoleParam::DISABLED;
 }
 
 }  // namespace init
diff --git a/init/first_stage_console.h b/init/first_stage_console.h
index 74853399b..8f36a7cbb 100644
--- a/init/first_stage_console.h
+++ b/init/first_stage_console.h
@@ -21,8 +21,15 @@
 namespace android {
 namespace init {
 
+enum FirstStageConsoleParam {
+    DISABLED = 0,
+    CONSOLE_ON_FAILURE = 1,
+    IGNORE_FAILURE = 2,
+    MAX_PARAM_VALUE = IGNORE_FAILURE,
+};
+
 void StartConsole();
-bool FirstStageConsole(const std::string& cmdline);
+int FirstStageConsole(const std::string& cmdline);
 
 }  // namespace init
 }  // namespace android
diff --git a/init/first_stage_init.cpp b/init/first_stage_init.cpp
index 5eca64457..1a608f65b 100644
--- a/init/first_stage_init.cpp
+++ b/init/first_stage_init.cpp
@@ -200,16 +200,16 @@ int FirstStageMain(int argc, char** argv) {
     }
 
     Modprobe m({"/lib/modules"}, module_load_file);
-    auto want_console = ALLOW_FIRST_STAGE_CONSOLE && FirstStageConsole(cmdline);
+    auto want_console = ALLOW_FIRST_STAGE_CONSOLE ? FirstStageConsole(cmdline) : 0;
     if (!m.LoadListedModules(!want_console)) {
-        if (want_console) {
+        if (want_console != FirstStageConsoleParam::DISABLED) {
             LOG(ERROR) << "Failed to load kernel modules, starting console";
         } else {
             LOG(FATAL) << "Failed to load kernel modules";
         }
     }
 
-    if (want_console) {
+    if (want_console == FirstStageConsoleParam::CONSOLE_ON_FAILURE) {
         StartConsole();
     }