How do you create a loadable kernel module for And

问题:

I know there a number of walkthroughs and tutorials floating around out there which describe this activity, but after having read many of them I still can't get this working. If anyone has the patience to wade through the steps I've taken (posted below) and suggest where I may have gone off track I'd be very appreciative. I've spent about a day and a half staring at make files and reading walkthroughs so literally any suggestions would be helpful.

Environment:

• I'm using an Ubuntu 10.04 32 bit vm.
• I'm hosting from a 64 bit windows 7
• My Core 2 Duo does not have the hardware support for 64 bit VMs so i'm trying to compile against Android 2.1 kernel
• I have installed Java 1.5 from the Dapper repo and removed my 1.6 installation
• The rest of the tooling has been acquired according the Android dev documentation...

As per Initializing a Build Environment:

Java:

$ sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu dapper main multiverse"
$ sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu dapper-updates main multiverse"
$ sudo apt-get update
$ sudo apt-get install sun-java5-jdk

Other required:

$ sudo apt-get install git-core gnupg flex bison gperf build-essential zip curl zlib1g-dev libc6-dev libncurses5-dev x11proto-core-dev libx11-dev libreadline5-dev libz-dev libgl1-mesa-dev
$ sudo apt-get install gcc-multilib g++-multilib libc6-i386 libc6-dev-i386

Then from Downloading the Source Tree:

Repo:

$ mkdir ~/bin
$ PATH=~/bin:$PATH
$ curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
$ chmod a+x ~/bin/repo
$ mkdir WORKING_DIRECTORY
$ cd WORKING_DIRECTORY
$ repo init -u https://android.googlesource.com/platform/manifest -b eclair
$ repo sync
$ gpg --import (imported the huge key)

And from Building the System:

Initialize:

$ source build/envsetup.sh

Choose a Target:

$ lunch generic-user

Build the Code:

$ make -j4

Added! Output of make -j4:

============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=2.1-update1
TARGET_PRODUCT=generic
TARGET_BUILD_VARIANT=eng
TARGET_SIMULATOR=
TARGET_BUILD_TYPE=release
TARGET_ARCH=arm
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=ECLAIR
============================================
build/core/copy_headers.mk:15: warning: overriding commands for target `out/target/product/generic/obj/include/libpv/getactualaacconfig.h'
build/core/copy_headers.mk:15: warning: ignoring old commands for target `out/target/product/generic/obj/include/libpv/getactualaacconfig.h'
/bin/bash: line 0: cd: sdk/layoutopt/app/src/resources: No such file or directory
Install: out/host/linux-x86/bin/acp
target Generated: libclearsilver-jni <= out/host/common/obj/JAVA_LIBRARIES/clearsilver_intermediates/javalib.jar
target Generated: libclearsilver-jni <= out/host/common/obj/JAVA_LIBRARIES/clearsilver_intermediates/javalib.jar
host SharedLib: libneo_cs (out/host/linux-x86/obj/lib/libneo_cs.so)
host C++: aapt <= frameworks/base/tools/aapt/AaptAssets.cpp
host C++: aapt <= frameworks/base/tools/aapt/Command.cpp
error: error reading out/host/common/obj/JAVA_LIBRARIES/clearsilver_intermediates/javalib.jar; error in opening zip file
error: error reading out/host/common/obj/JAVA_LIBRARIES/clearsilver_intermediates/javalib.jar; error in opening zip file
error: error reading out/host/common/obj/JAVA_LIBRARIES/clearsilver_intermediates/javalib.jar; cannot read zip file
error: cannot access org.clearsilver.HDF
class file for org.clearsilver.HDF not found
javadoc: error - Class org.clearsilver.HDF not found.
Error: No classes were specified on the command line.  Try -help.
make: *** [out/host/linux-x86/obj/SHARED_LIBRARIES/libclearsilver-jni_intermediates/org_clearsilver_HDF.h] Error 15
make: *** Waiting for unfinished jobs....
error: error reading out/host/common/obj/JAVA_LIBRARIES/clearsilver_intermediates/javalib.jar; cannot read zip file
error: cannot access org.clearsilver.CS
class file for org.clearsilver.CS not found
In file included from frameworks/base/tools/aapt/AaptAssets.h:18,
                 from frameworks/base/tools/aapt/AaptAssets.cpp:5:
frameworks/base/tools/aapt/ZipFile.h:65: warning: ‘typedef’ was ignored in this declaration
javadoc: error - Class org.clearsilver.CS not found.
Error: No classes were specified on the command line.  Try -help.
In file included from frameworks/base/tools/aapt/AaptAssets.h:18,
                 from frameworks/base/tools/aapt/Main.h:14,
                 from frameworks/base/tools/aapt/Command.cpp:6:
frameworks/base/tools/aapt/ZipFile.h:65: warning: ‘typedef’ was ignored in this declaration
make: *** [out/host/linux-x86/obj/SHARED_LIBRARIES/libclearsilver-jni_intermediates/org_clearsilver_CS.h] Error 15

Added!

So it turns out i've got some problems here. I assume that once i've overcome these issues, i'll have an environment capable of compiling kernel modules. Please do correct me if I'm wrong.

Next I head into my directory containing my module.c file and it's makefile. Contents of makefile below:

obj-m += mymodule.o

CROSS_COMPILE=~/WORKING_DIRECTORY/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi-
KERNEL_DIR ?= /home/<myuser>/WORKING_DIRECTORY
VERSION = v1.1



all:
    make -C $(KERNEL_DIR) M=$(PWD) ARCH=arm CROSS_COMPILE=$(CROSS_COMPILE) modules
    rm -rf *.c~
    rm -rf *.mod*
    rm -rf *.o
clean:
    make -C $(KERNEL_DIR) M=$(PWD) clean

I have very little experience with make and makefiles, but this looked reasonable to me. My main concern with this file is the KERNEL-DIR variable. I tried a few different values for that variable, but got all sorts of errors where I do not with it's current value. Of course, it could still be wrong, so any comments here are welcome.

So, as far as I know, I should be able to execute make with no args or anything and will figure out what it needs to do. I have tried make, make -f both with and without sudo. All four permutations yield the same results:

make -C /home/<myuser>/WORKING_DIRECTORY M=/home/<myuser>/Desktop/<MyModuleDir> ARCH=arm CROSS_COMPILE=~/WORKING_DIRECTORY/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- modules
============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=2.1-update1
TARGET_PRODUCT=generic
TARGET_BUILD_VARIANT=eng
TARGET_SIMULATOR=
TARGET_BUILD_TYPE=release
TARGET_ARCH=arm
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=ECLAIR
============================================
make[1]: Entering directory `/home/<myuser>/WORKING_DIRECTORY'
build/core/copy_headers.mk:15: warning: overriding commands for target `out/target/product/generic/obj/include/libpv/getactualaacconfig.h'
build/core/copy_headers.mk:15: warning: ignoring old commands for target `out/target/product/generic/obj/include/libpv/getactualaacconfig.h'
/bin/bash: line 0: cd: sdk/layoutopt/app/src/resources: No such file or directory
Available sub-modules:
01-test                     dumpsys                     libminui                    LotsOfApps
20-dns.conf                 dvz                     libminzip                   lowstoragetest
95-configured                   dx                      libmp4recognizer_utility            lsd
aapt                        dx-tests                    libmtdutils                 LunarLander
acc                     edify                       libnativehelper                 LunarLanderTests
AccountAndSyncSettings              Email                       libneo_cgi                  MagicSmokeWallpapers
accRuntimeTest                  EmailTests                  libneo_cs                   make_cfst
acp                     emma                        libneo_util                 makedict
adb                     emmalib                     libnetutils                 make_g2g
adbd                        emulator                    libocr                      makekeycodes
add-property-tag                emulator-arm                    libomx_aac_component_lib            make_ve_grammar
afar                        emulator-hw                 libomx_aacdec_sharedlibrary         mediaframeworktest
aidl                        emulator-tcg                    libomx_amr_component_lib            MediaProvider
AlarmClock                  EnabledTestApp                  libomx_amrdec_sharedlibrary         mediaserver
AliasActivity                   etc1tool                    libomx_amrenc_component_lib         memtest
am                      eventanalyzer                   libomx_amrenc_sharedlibrary         minigzip
android                     event-log-tags                  libomx_avc_component_lib            mkbootfs
android.core.tests.annotation           exc_dump                    libomx_avcdec_sharedlibrary         mkbootimg
android.core.tests.archive          ext                     libomx_baseclass_lib                mksdcard
android.core.tests.concurrent           Fallback                    libomx_common_lib               mkstubs
android.core.tests.crypto           fastboot                    libomx_m4v_component_lib            mkyaffs2image
android.core.tests.dom              FixedGridLayout                 libomx_m4vdec_sharedlibrary         Mms
android.core.tests.logging          flash_image                 libomx_mastercore_lib               MmsTests
android.core.tests.luni.io          FontLab                     libomx_mp3_component_lib            monkey
android.core.tests.luni.lang            framework                   libomx_mp3dec_sharedlibrary         monkeyrunner
android.core.tests.luni.net         FrameworkPermissionTests            libomx_queue_lib                mtpd
android.core.tests.luni.util            framework-res                   libomx_sharedlibrary                MultiResolution
android.core.tests.math             FrameworkTest                   libop                       Music
android.core.tests.nio              framework-tests                 libopencore_author              MusicTests
android.core.tests.nio_char         FrameworkTestTests              libopencore_common              nc
android.core.tests.prefs            fsck_msdos                  libopencore_download                netcfg
android.core.tests.regex            fs_config                   libopencore_downloadreg             netperf
android.core.tests.runner           fs_get_stats                    libopencore_mp4local                netserver
android.core.tests.security         Gallery                     libopencore_mp4localreg             ninepatch
android.core.tests.sql              Gallery3D                   libopencore_net_support             NinePatchLab
android.core.tests.text             GalleryTests                    libopencore_player              NoShareUidApp
android.core.tests.xml              gdbserver                   libopencore_rtsp                NotePad
android.core.tests.xnet             genext2fs                   libopencore_rtspreg             NotePadTests
android.cts.dpi                 GestureBuilder                  libosclbase                 opcontrol
android.cts.refapp              GL2JNI                      libosclerror                    openssl
android.policy                  GLJNI                       libosclio                   OpenWnn
android.policy_mid              GlobalSearch                    liboscllib                  oprofiled
android.policy_phone                GlobalSearchBenchmarks              libosclmemory                   org.eclipse.core.commands_3.4.0.I20080509-2000
androidprefs                    GlobalSearchPermissionTests         libosclproc                 org.eclipse.equinox.common_3.4.0.v20080421-2006
android.test.runner             GlobalSearchTests               libosclregcli                   org.eclipse.jface_3.4.2.M20090107-0800
AndroidTests                    GlobalTime                  libosclregserv                  org-netbeans-api-visual
angeles                     GoogleContactsProvider              libosclutil                 org-openide-util
ant                     GoogleContactsProviderTests         libpagemap                  osgi
antlr-2.7.7                 google-framework                libpassthru_oma1                PackageInstaller
anttasks                    googlelogin-client              libpcap                     parseStringTest
apicheck                    GoogleSearch                    libpixelflinger                 perm_checker
ApiDemos                    gpustate                    libpixelflinger_armv6               perm_checker.conf
ApiDemosReferenceTest               gralloc.default                 libpixelflinger_static              Phone
ApiDemosTests                   groovy-all-1.6.5                libplatform_library_jni             PicoTts
apkbuilder                  grxmlcompile                    libpng                      ping
ApplicationsProvider                gtest-filepath_test             libpopt                     PinyinIME
applypatch                  gtest-linked_ptr_test               libprotocolenginenode_base          PlatformLibraryClient
applypatch_static               gtest-message_test              libprotocolenginenode_common            platform.xml
app_process                 gtest-options_test              libprotocolenginenode_download_common       pm
AppWidgetHostTest               gtest-port_test                 libprotocolenginenode_pdl           post_trace
AppWidgetProvider               gtest_pred_impl_unittest            libprotocolenginenode_ps            pppd
apriori                     gtest_prod_test                 libpv_aac_dec                   preload
archquery                   gtest-test-part_test                libpvaacffparsernode                ProcessTests
asm-3.1                     gtest-typed-test2_test              libpvaacffrecognizer                procmem
atree                       gtest-typed-test_test               libpvaacparser                  procrank
AudioHardwareRecord             gtest_unittest                  libpvamrffparsernode                profile_pid
AudioHardwareRecordLoop             gzip                        libpvamrffrecognizer                profile_trace
AudioInRecord                   HelloActivity                   libpv_amr_nb_common_lib             Provision
backup_helper_test              HelloActivityTests              libpvamrwbdecoder               pvplayer
BackupTest                  hierarchyviewer                 libpvauthorengine               q2dm
BatteryWaster                   hist_trace                  libpv_avc_common_lib                q2g
bb2sym                      Home                        libpvavcdecoder                 qemud
bb_dump                     hosttestlib                 libpvavifileparser              qemu-props
bbprof                      hprof-conv                  libpv_config_parser             qwerty2.kcm
bison                       HTMLViewer                  libpvdecoder_gsmamr             qwerty.kcm
Bluetooth                   icache                      libpvdownloadinterface              racoon
BluetoothChat                   icudata                     libpvdownloadmanagernode            radiooptions
BluetoothDebug                  idegen                      libpvdownloadreginterface           read_addr
bmgr                        ime                     libpvencoder_gsmamr             read_method
bookmarks.xml                   ImfTest                     libpvfileoutputnode             read_pid
bootanimation                   ImfTestTests                    libpvfileparserutils                read_trace
Browser                     imgdiff                     libpvframemetadatautility           recovery
BrowserPowerTests               init                        libpvgendatastruct              required_hardware.xml
BrowserTestPlugin               input                       libpvgsmamrparser               rgb2565
BrowserTests                    installd                    libpv_http_parcom               rild
bsdiff                      invoke_mock_media_player            libpvid3parcom                  rsg-generator
bspatch                     iptables                    libpvjitterbuffer               RSSReader
btool                       ip-up-vpn                   libpvjitterbuffernode               run-core-tests
bugreport                   iself                       libpvjitterbufferrtp                run-core-tests-on-ri
BusinessCard                    isprelinked                 libpvlatmpayloadparser              safe_iop_test
Calculator                  jarjar                      libpvmediadatastruct                SampleBrowserPlugin
CalculatorTests                 jarutils                    libpvmediainputnode             schedtest
Calendar                    jasmin                      libpvmedialayernode             scp
CalendarProvider                jasmin.jar                  libpvmediaoutputnode                screenshot2
CalendarProviderTests               javax.obex                  libpvmf                     sdklib
CalendarTests                   jcommon-1.0.12                  libpvmfrecognizer               sdkmanager
Camera                      jdiff                       libpvmimeutils                  SdkSetup
CameraTests                 jdwpspy                     libpvmioaviwavfileinput             sdkstats
CertInstaller                   JETBoy                      libpvmiofileinput               sdkuilib
cfassembler                 jfreechart-1.0.9                libpvmiofileoutput              sdutil
check-lost+found                jfreechart-1.0.9-swt                libpvmp3                    SearchableDictionary
check_prereq                    junit                       libpvmp3ff                  sensors.goldfish
check_stack                 jython                      libpvmp3ffparsernode                service
check_trace                 kcm                     libpvmp3ffrecognizer                servicemanager
clearsilver                 keystore                    libpvmp4decoder                 services
cmu2nuance                  keystore_cli                    libpvmp4ff                  Settings
com.android.inputmethod.pinyin.lib      KeyStoreTests                   libpvmp4ffcomposer              SettingsProvider
com.example.android.platform_library        kxml2-2.3.0                 libpvmp4ffcomposernode              SettingsTests
commons-compress-1.0                latencytop                  libpvmp4ffparsernode                sh
Compass                     LatinIME                    libpvmp4ffrecognizer                ShareUidApp
ContactManager                  Launcher                    libpvmp4interface               showlease
Contacts                    Launcher2                   libpvmp4reginterface                showmap
ContactsProvider                launchperf                  libpvomxaudiodecnode                showslab
ContactsProviderTests               layoutlib                   libpvomxbasedecnode             sig
ContactsTests                   layoutlib_api                   libpvomxencnode                 sig-check
core                        layoutlib_create                libpv_omx_interface             sig-create
core-tests                  layoutlib_utils                 libpvomx_proxy_lib              signapk
CoreTests                   layoutopt                   libpvomxvideodecnode                SignatureTest
coverage                    libabi                      libpvplayer_engine              SignatureTestTests
cpueater                    libacc                      libpvpvxparser                  signature-tools
cpufeatures                 libaes                      libpvrtsp_cli_eng_node              SimpleJNI
crasher                     libandroidpv                    libpvrtspinterface              SkeletonApp
create_test_dmtrace             libandroidpvauthor              libpv_rtsp_parcom               SkeletonAppTests
cts                     libandroid_runtime              libpvrtspreginterface               skia_bench
CtsAccessibilityServiceTestCases        libandroid_servers              libpvsdpparser                  skia_gm
CtsAccountManagerTestCases          libapplypatch                   libpvsocketnode                 SlowSuggestions
CtsAppAccessData                libarity                    libpvstreamingmanagernode           SmokeTest
CtsAppSecurityTests             libastl                     libpvthreadmessaging                SmokeTestApp
CtsAppTestCases                 libaudioflinger                 libpvwav                    Snake
CtsAppWithData                  libaudiointerface               libpvwavffparsernode                SnakeTests
CtsBluetoothTestCases               libaudiopolicygeneric               libpvwavffrecognizer                SoftKeyboard
CtsContentTestCases             libbinder                   librank                     soslim
cts-dalvik-buildutil                libbz                       libreference-cdma-sms               sound
CtsDatabaseTestCases                libc                        libreference-ril                SoundRecorder
CtsDelegatingAccessibilityService       libcameraservice                libril                      SpammySuggestions
CtsDpiTestCases                 libcamerastub                   libRS                       SpareParts
CtsDpiTestCases2                libc_common                 librs_jni                   spec-progress
CtsExampleTestCases             libc_debug                  librtppayloadparser             sqlite3
CtsGestureTestCases             libclearsilver-jni              librtprtcp                  SRecTest
CtsGraphicsTestCases                libc_nomalloc                   libsafe_iop                 SRecTestAudio
CtsHardwareTestCases                libcolorconvert                 libsampleplugin                 ssh
CtsInstrumentationAppDiffCert           libcpm                      libSDL                      SslLoad
CtsJniTestCases                 libcrypto                   libSDLmain                  stack_dump
CtsLocationTestCases                libctest                    libsimplejni                    StatusBarTest
CtsMediaTestCases               libcts_jni                  libskia                     Stk
CtsNetTestCases                 libctspermission_jni                libskiagl                   strace
CtsOsTestCases                  libcutils                   libsonivox                  stringtemplate
CtsPerformance2TestCases            libdb                       libsoundpool                    su
CtsPerformance3TestCases            libdbus                     libspeex                    surfaceflinger
CtsPerformance4TestCases            libdbus-tools-common                libsqlite                   svc
CtsPerformance5TestCases            libdex                      libsqlite3_android              swing-worker-1.1
CtsPerformanceTestCases             libdl                       libsqlite3_phone_number_utils_test      swt
CtsPermission2TestCases             libdrm1                     libsqlite3_phonetic_string_utils_test       system_server
CtsPermissionDeclareApp             libdrm1_jni                 libSR_AcousticModels                tcpdump
CtsPermissionTestCases              libdrm2                     libSR_AcousticState             TelephonyProvider
CtsProviderTestCases                libdvm                      libSR_AudioIn                   telephonytest
CtsSharedUidInstall             libebl                      libSR_Core                  temp_layoutlib
CtsSharedUidInstallDiffCert         libebl_arm                  libsrec_jni                 Term
CtsSimpleAppInstall             libedify                    libSR_EventLog                  test_defs.xml
CtsSimpleAppInstallDiffCert         libEGL                      libSR_G2P                   TestDeviceSetup
CtsSpeechTestCases              libelf                      libSR_Grammar                   test-fb-refresh
CtsTargetInstrumentationApp         libelfcopy                  libSR_Nametag                   test-fb-simple
CtsTelephonyTestCases               libembunit                  libSR_Recognizer                test_g2g
CtsTestStubs                    libemoji                    libSR_Semproc                   test-mdp
CtsTextTestCases                libESR_Portable                 libSR_Session                   test-opengl-codegen
CtsUsePermissionDiffCert            libESR_Shared                   libSR_Vocabulary                test-opengl-fillrate
CtsUtilTestCases                libETC1                     libssl                      test-opengl-filter
CtsViewTestCases                libexif                     libstagefright                  test-opengl-finish
CtsWebkitTestCases              libexpat                    libstagefright_omx              test-opengl-gl2_basic
CtsWidgetTestCases              libext                      libstdc++                   test-opengl-gl_basic
CubeLiveWallpapers              libfdlibm                   libsurfaceflinger               test-opengl-gralloc
CustomLocale                    libFFTEm                    libsvoxpico                 test-opengl-linetex
daemonize                   libfst                      libsystem_server                test-opengl-swapinterval
dalvikvm                    libft2                      libsysutils                 test-opengl-textures
dasm                        libgetactualaacconfig               libterm                     test-opengl-tritex
dbus-daemon                 libgif                      libtestplugin                   test-progress
dbus-monitor                    libgl2jni                   libthread_db                    test-progress-new
dbus-send                   libGLES_android                 libthreadsafe_callback_ao           test_swiarb
ddmlib                      libGLESv1_CM                    libtinyxml                  test_zipfile
ddms                        libGLESv2                   libtomcrypt                 timeinfo
ddmuilib                    libgljni                    libtommath                  timetest
debuggerd                   libgoogleclient                 libttspico                  toolbox
DensityTest                 libgtest                    libttssynthproxy                traceview
descGen                     libgtest_main                   libui                       TransformTest
DeskClock                   libhardware                 libunz                      TtsService
Development                 libhardware_legacy              libutil                     tuttle2.kcm
dexdeps                     libhost                     libutils                    uix
dexdump                     libicudata-default              libvorbisidec                   updater
dexlist                     libicudata-eu                   libwbxml                    UpgradeExample
dexopt                      libicudata-jp                   libwbxml_jni                    usbtest
dexopt-wrapper                  libicudata-large                libwebcore                  UserDictionaryProvider
dexpreopt                   libicudata-us                   libwnndict                  VisualizationWallpapers
dex-tools                   libicui18n                  libWnnEngDic                    vm-tests
dhcpcd                      libicuuc                    libWnnJpnDic                    VoiceDialer
dhcpcd-run-hooks                libiptc                     libwpa_client                   Voiper
dictTest                    libjavacore                 libxml2                     vold
DisabledTestApp                 libjni_latinime                 libxml2wbxml                    VpnServices
dmtracedump                 libjni_pinyinime                libz                        wbxmltest
DownloadProvider                libjnitest                  libzipfile                  wdsclient
draw9patch                  libjpeg                     LightingTest                    webkitmerge
DrmProvider                 liblog                      line_endings                    Wiktionary
droiddoc                    libm                        linker                      WiktionarySimple
dumpeventlog                    libm4v_config                   LiveWallpapers                  xmlwriter
dumpkey                     libmedia                    LiveWallpapersPicker                yuv420sp2rgb
dump_regions                    libmedia_jni                    localize                    zipalign
DumpRenderTree                  libmediaplayerservice               logcat
dumpstate                   libmincrypt                 logwrapper
make[1]: Leaving directory `/home/<myuser>/WORKING_DIRECTORY'
rm -rf *.c~
rm -rf *.mod*
rm -rf *.o

You'll notice a few screwy warnings, but as best as I can tell, they are not real problems. If anyone feels differently about these, please say so.

make[1]: Entering directory `/home/<myuser>/WORKING_DIRECTORY'
build/core/copy_headers.mk:15: warning: overriding commands for target     `out/target/product/generic/obj/include/libpv/getactualaacconfig.h'
build/core/copy_headers.mk:15: warning: ignoring old commands for target     `out/target/product/generic/obj/include/libpv/getactualaacconfig.h'
/bin/bash: line 0: cd: sdk/layoutopt/app/src/resources: No such file or directory

I guess that last line sounds pretty suspicious but I have no idea what to do about it. Apart from the few strange things i've mentioned, it would appear that this all went smoothly. However, after the whole thing completes, I can't find the *.ko file anywere. I did a ls -alRg | grep *.ko on my home directory and it turns up nothing. I'm stumped. If I can provide any more information or run any tests or try anything differently i'll be checking in frequently.

回答1:

Sorry for being late, but hope it helps:

http://tthtlc.wordpress.com/2011/12/29/how-to-write-a-kernel-module-on-android-sony-ericsson-xperia-arc-s/

I wrote and tested the code on my Sony Ericsson Xperia Arc S and it works (in general in should work for any Android phone).

Connecting via adb and USB, and “su” to root, the “lsmod” listed all the kernel module (in general, the article at http://developer.sonyericsson.com/wp/2011/05/06/how-to-build-a-linux-kernel/ gave a very good coverage of what to do in Linux kernel compilation for SonyEricsson phone):

lsmod
android_module 654 0 - Live 0x7f007000 (P)
sdio 16532 0 - Live 0x7f000000

“android_module” was the one I had inserted via insmod android_module.ko.

Here’s how to do it:

First the original program was copied from:

http://rechtzeit.wordpress.com/2011/03/21/77/

Or reproduced as follows:

android_module.c:

#include"linux/module.h"
#include"linux/kernel.h"
//replace the "" with angular brackets
int init_module(void)
{
  printk(KERN_INFO "Hello android kernel...\n");
  return 0;
}

void cleanup_module(void)
{
  printk(KERN_INFO "Goodbye android kernel...\n");
}

Makefile:

obj-m += android_module.o

all:
make -C /home/tteikhua/android/sony_ericsson_src/58/kernel/ M=$(PWD) modules
clean:
make -C /home/tteikhua/android/sony_ericsson_src/58/kernel/ M=$(PWD) clean

The directory where the kernel is located (“-C” above) is where I had downloaded the SonyEricsson kernel image from here:

http://developer.sonyericsson.com/wportal/devworld/downloads/download/30a2181182tarbz2?cc=gb&lc=en

And the following command will use the Makefile from above:

ARCH=arm CROSS_COMPILE=/opt/CodeSourcery/Sourcery_G++_Lite/bin/arm-none-linux-gnueabi- make

As shown above, the cross compiler I had used is from CodeSourcery.

And after insmod android_module.ko you can see the debugging message in dmesg output:

 <6>[11184.063507] Hello android kernel...
 <7>[11619.209655] msmrtc_timeremote_set_time: 11/29/2011 10:09:36 (04)
 <6>[11619.210418] RPC CALL -- TOD TIME UPDATE: ttick = 404244221
 <6>[11619.210418] stamp=52910543933046785, freq = 0
 <7>[11619.211578] msmrtc_tod_proc_result: 12/29/2011 10:09:36 (03)
 <6>[11619.211578] rs30000048 rs30000048.262144: setting system clock to 2011-12-29 10:09:36 UTC (1325153376)
 <6>[11662.112365] device rmnet0 left promiscuous mode
 <6>[11662.112579] device rmnet0 entered promiscuous mode
 <6>[11669.958221] device rmnet0 left promiscuous mode
 <6>[11669.958435] device rmnet0 entered promiscuous mode
 <7>[11698.181060] msmrtc_timeremote_set_time: 11/29/2011 10:10:55 (04)
 <6>[11698.187622] RPC CALL -- TOD TIME UPDATE: ttick = 406832008
 <6>[11698.187652] stamp=52910548228014081, freq = 0
 <7>[11698.193939] msmrtc_tod_proc_result: 12/29/2011 10:10:55 (03)
 <6>[11698.194030] rs30000048 rs30000048.262144: setting system clock to 2011-12-29 10:10:55 UTC (1325153455)
 <6>[11814.442901] bq27520 0-0055: bq27520_handle_soc_worker() capacity=97 (100) flags=0x229 ctrl_status=0x28b soh_state=0x3, valid=1
 <6>[11984.057373] Goodbye android kernel...

And the “Goodbye” is when rmmod android_module is executed. In between are debugging message from other components in the kernel.

回答2:

I think I've red that emulator kernel does not support module, so you must compile also the kernel with modules support.

I hope that this link will help you

回答3:

There are two things you'll need to do. Firstly, create an emulator kernel that supports loadable kernel modules.

There's a comprehensive post here covering the process of setting up the emulator kernel.

There are 2 parts of the instructions to alter:

1. I find it easiest to keep the kernel within the repo area (in this case, ~/WORKING_DIRECTORY), like so:

   cd ~/WORKING_DIRECTORY
   mkdir kernel
   cd kernel
   git clone git://android.git.kernel.org/kernel/common.git
   

2. The branch information is no longer correct, however, so where it says:

   git checkout -t origin/android-goldfish-2.6.29 -b goldfish
   

use this instead:

    git checkout -t archive/android-gldfish-2.6.29 -b goldfish

As you've found out, the kernel by default is not configured with loadable module support. Enable before compiling. After, this step:

make ARCH=arm goldfish_defconfig

do this:

make ARCH=arm menuconfig

A text-based menu will show up. Use the Up/Down arrow keys to navigate, Space to select an option, Enter to expand a menu (menus have --->) at the end of the line, and Esc-Esc to go back a menu.

1. Select "Enable loadable module support" by scrolling down and hitting Space
2. Hit Esc-Esc to exit, and hit Enter to save the new configuration

Now build. Using your setup, it would be:

make ARCH=arm CROSS_COMPILE=/home/<myuser>/WORKING_DIRECTORY/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi-

Now that that's done you can do the second part, which is making a loadable kernel module. You were almost there, but because you didn't have the kernel source for the emulator, it didn't work. Just take the makefile you have and change KERNEL_DIR to:

KERNEL_DIR ?= /home/<myuser>/WORKING_DIRECTORY/kernel/common