[Android Q&A, Help & Troubleshooting] ulgsm4u:
C:\OT981>fastboot boot boot_adb.img
< waiting for device >
downloading 'boot.img'...
OKAY [ 0.953s]
booting...
OKAY [ 0.141s]
finished. total time: 1.094s

C:\OT981>
C:\OT981>
C:\OT981>adb root
adbd is already running as root

C:\OT981>
C:\OT981>adb remount
remount failed: Unknown error: 0

C:\OT981>fastboot erase system -w
< waiting for device >
erasing 'system'...
OKAY [ 0.313s]
erasing 'userdata'...
OKAY [ 0.750s]
erasing 'cache'...
OKAY [ 0.219s]
finished. total time: 1.281s

C:\OT981>
C:\OT981>fastboot boot boot_adb.img
downloading 'boot.img'...
OKAY [ 0.938s]
booting...
OKAY [ 0.156s]
finished. total time: 1.094s

C:\OT981>adb root
adbd is already running as root

C:\OT981>
C:\OT981>adb remount
remount failed: Unknown error: 0

C:\OT981>adb remount
remount failed: Unknown error: 0

C:\OT981>adb shell
/ # cd system
cd system
/bin/sh: cd: can't cd to system
/ #

/ #

/ # mount /dev/block/mtdblock4 /system
mount /dev/block/mtdblock4 /system
mount: mounting /dev/block/mtdblock4 on /system failed: No such file or director
y
/ #exit

C:\OT981>adb shell
/ #

/ # cat /proc/mtd
cat /proc/mtd
dev: size erasesize name
mtd0: 00500000 00020000 "boot"
mtd1: 03200000 00020000 "cache"
mtd2: 00500000 00020000 "recovery"
mtd3: 00060000 00020000 "splash"
mtd4: 04880000 00020000 "system"
mtd5: 08200000 00020000 "custpack"
mtd6: 0b0c0000 00020000 "userdata"
mtd7: 00080000 00020000 "studypara"
/ #

/ # mkdir /system
mkdir /system
/ #

/ # mount /dev/block/mtdblock4 /system
mount /dev/block/mtdblock4 /system
/ #

/ # exit
exit

C:\OT981>adb root
adbd is already running as root

C:\OT981>adb remount
remount succeeded

C:\OT981>adb push .\system /system
push: .\system/app/Wiper.apk -> /system/app/Wiper.apk
push: .\system/app/VpnServices.apk -> /system/app/VpnServices.apk
push: .\system/app/VisualizationWallpapers.apk -> /system/app/VisualizationWallp
apers.apk
push: .\system/app/UserDictionaryProvider.apk -> /system/app/UserDictionaryProvi
der.apk
push: .\system/app/TtsService.apk -> /system/app/TtsService.apk
push: .\system/app/TSCalibration.apk -> /system/app/TSCalibration.apk
push: .\system/app/Term.apk -> /system/app/Term.apk
push: .\system/app/TelephonyProvider.apk -> /system/app/TelephonyProvider.apk
push: .\system/app/TaskManager.apk -> /system/app/TaskManager.apk
push: .\system/app/SyncMLClient.apk -> /system/app/SyncMLClient.apk
push: .\system/app/Superuser.apk -> /system/app/Superuser.apk
push: .\system/app/Stk.apk -> /system/app/Stk.apk
push: .\system/app/Sound.apk -> /system/app/Sound.apk
push: .\system/app/SettingsProvider.apk -> /system/app/SettingsProvider.apk
push: .\system/app/Settings.apk -> /system/app/Settings.apk
push: .\system/app/SecureClock.apk -> /system/app/SecureClock.apk
push: .\system/app/QualcommSettings.apk -> /system/app/QualcommSettings.apk
push: .\system/app/PicoTts.apk -> /system/app/PicoTts.apk
push: .\system/app/Phone.apk -> /system/app/Phone.apk
push: .\system/app/PermissionToAccessLocApi.apk -> /system/app/PermissionToAcces
sLocApi.apk
push: .\system/app/PDFViewer.apk -> /system/app/PDFViewer.apk
push: .\system/app/PackageInstaller.apk -> /system/app/PackageInstaller.apk
push: .\system/app/OTAProvisioningClient.apk -> /system/app/OTAProvisioningClien
t.apk
push: .\system/app/Notes.apk -> /system/app/Notes.apk
push: .\system/app/Music.apk -> /system/app/Music.apk
push: .\system/app/Mms.apk -> /system/app/Mms.apk
push: .\system/app/MMITestdev.apk -> /system/app/MMITestdev.apk
push: .\system/app/MediaProvider.apk -> /system/app/MediaProvider.apk
push: .\system/app/MagicSmokeWallpapers.apk -> /system/app/MagicSmokeWallpapers.
apk
push: .\system/app/LiveWallpapers.apk -> /system/app/LiveWallpapers.apk
push: .\system/app/Launcher.apk -> /system/app/Launcher.apk
push: .\system/app/LatinIME.apk -> /system/app/LatinIME.apk
push: .\system/app/HTMLViewer.apk -> /system/app/HTMLViewer.apk
push: .\system/app/HmAgent.apk -> /system/app/HmAgent.apk
push: .\system/app/GlobalSearch.apk -> /system/app/GlobalSearch.apk
push: .\system/app/FileManager.apk -> /system/app/FileManager.apk
push: .\system/app/Email.apk -> /system/app/Email.apk
push: .\system/app/DrmUtility.apk -> /system/app/DrmUtility.apk
push: .\system/app/DrmProvider.apk -> /system/app/DrmProvider.apk
push: .\system/app/DownloadProvider.apk -> /system/app/DownloadProvider.apk
push: .\system/app/ContactsProvider.apk -> /system/app/ContactsProvider.apk
push: .\system/app/Contacts.apk -> /system/app/Contacts.apk
push: .\system/app/CertInstaller.apk -> /system/app/CertInstaller.apk
push: .\system/app/Camera.apk -> /system/app/Camera.apk
push: .\system/app/CalendarProvider.apk -> /system/app/CalendarProvider.apk
push: .\system/app/Calendar.apk -> /system/app/Calendar.apk
push: .\system/app/Calculator.apk -> /system/app/Calculator.apk
push: .\system/app/Browser.apk -> /system/app/Browser.apk
push: .\system/app/Bluetooth.apk -> /system/app/Bluetooth.apk
push: .\system/app/ApplicationsProvider.apk -> /system/app/ApplicationsProvider.
apk
push: .\system/app/AlarmClock.apk -> /system/app/AlarmClock.apk
push: .\system/app/AccountAndSyncSettings.apk -> /system/app/AccountAndSyncSetti
ngs.apk
push: .\system/bin/wpa_supplicant -> /system/bin/wpa_supplicant
push: .\system/bin/wiperiface -> /system/bin/wiperiface
push: .\system/bin/wipe -> /system/bin/wipe
push: .\system/bin/watchprops -> /system/bin/watchprops
push: .\system/bin/vold -> /system/bin/vold
push: .\system/bin/vmstat -> /system/bin/vmstat
push: .\system/bin/updater -> /system/bin/updater
push: .\system/bin/umount -> /system/bin/umount
push: .\system/bin/tune2fs -> /system/bin/tune2fs
push: .\system/bin/top -> /system/bin/top
push: .\system/bin/toolbox -> /system/bin/toolbox
push: .\system/bin/test_diag -> /system/bin/test_diag
push: .\system/bin/system_server -> /system/bin/system_server
push: .\system/bin/sync -> /system/bin/sync
push: .\system/bin/svc -> /system/bin/svc
push: .\system/bin/surfaceflinger -> /system/bin/surfaceflinger
push: .\system/bin/stop -> /system/bin/stop
push: .\system/bin/start -> /system/bin/start
push: .\system/bin/spp_test -> /system/bin/spp_test
push: .\system/bin/smd -> /system/bin/smd
push: .\system/bin/sleep -> /system/bin/sleep
push: .\system/bin/sh -> /system/bin/sh
push: .\system/bin/setprop -> /system/bin/setprop
push: .\system/bin/setconsole -> /system/bin/setconsole
push: .\system/bin/servicemanager -> /system/bin/servicemanager
push: .\system/bin/service -> /system/bin/service
push: .\system/bin/sendevent -> /system/bin/sendevent
push: .\system/bin/sdptool -> /system/bin/sdptool
push: .\system/bin/schedtop -> /system/bin/schedtop
push: .\system/bin/schedtest -> /system/bin/schedtest
push: .\system/bin/route -> /system/bin/route
push: .\system/bin/romdump -> /system/bin/romdump
push: .\system/bin/rmt_storage -> /system/bin/rmt_storage
push: .\system/bin/rmmod -> /system/bin/rmmod
push: .\system/bin/rmdir -> /system/bin/rmdir
push: .\system/bin/rm -> /system/bin/rm
push: .\system/bin/rild -> /system/bin/rild
push: .\system/bin/resize2fs -> /system/bin/resize2fs
push: .\system/bin/renice -> /system/bin/renice
push: .\system/bin/recovery -> /system/bin/recovery
push: .\system/bin/reboot -> /system/bin/reboot
push: .\system/bin/readmtd -> /system/bin/readmtd
push: .\system/bin/racoon -> /system/bin/racoon
push: .\system/bin/qmuxd -> /system/bin/qmuxd
push: .\system/bin/ps -> /system/bin/ps
push: .\system/bin/printenv -> /system/bin/printenv
push: .\system/bin/pppd -> /system/bin/pppd
push: .\system/bin/port-bridge -> /system/bin/port-bridge
push: .\system/bin/pm -> /system/bin/pm
push: .\system/bin/PktRspTest -> /system/bin/PktRspTest
push: .\system/bin/ping -> /system/bin/ping
push: .\system/bin/nvcmd -> /system/bin/nvcmd
push: .\system/bin/notify -> /system/bin/notify
push: .\system/bin/newfs_msdos -> /system/bin/newfs_msdos
push: .\system/bin/netstat -> /system/bin/netstat
push: .\system/bin/netcfg -> /system/bin/netcfg
push: .\system/bin/mverproxy -> /system/bin/mverproxy
push: .\system/bin/mv -> /system/bin/mv
push: .\system/bin/mtpd -> /system/bin/mtpd
push: .\system/bin/mount -> /system/bin/mount
push: .\system/bin/monkey -> /system/bin/monkey
push: .\system/bin/mm-venc-omx-test -> /system/bin/mm-venc-omx-test
push: .\system/bin/mm-vdec-omx-test -> /system/bin/mm-vdec-omx-test
push: .\system/bin/mm-qcamera-testsuite-client -> /system/bin/mm-qcamera-testsui
te-client
push: .\system/bin/mm-qcamera-test -> /system/bin/mm-qcamera-test
push: .\system/bin/mm-jpeg-enc-test -> /system/bin/mm-jpeg-enc-test
push: .\system/bin/mm-jpeg-dec-test -> /system/bin/mm-jpeg-dec-test
push: .\system/bin/mm-audio-native-test -> /system/bin/mm-audio-native-test
push: .\system/bin/mm-audio-mvs-test -> /system/bin/mm-audio-mvs-test
push: .\system/bin/mm-audio-ctrl-test -> /system/bin/mm-audio-ctrl-test
push: .\system/bin/mm-audio-alsa-test -> /system/bin/mm-audio-alsa-test
push: .\system/bin/mm-aenc-omxqcelp13-test -> /system/bin/mm-aenc-omxqcelp13-tes
t
push: .\system/bin/mm-aenc-omxevrc-test -> /system/bin/mm-aenc-omxevrc-test
push: .\system/bin/mm-aenc-omxamr-test -> /system/bin/mm-aenc-omxamr-test
push: .\system/bin/mm-aenc-omxaac-test -> /system/bin/mm-aenc-omxaac-test
push: .\system/bin/mm-adspsvc-test -> /system/bin/mm-adspsvc-test
push: .\system/bin/mm-adec-omxwma-test -> /system/bin/mm-adec-omxwma-test
push: .\system/bin/mm-adec-omxQcelp13-test -> /system/bin/mm-adec-omxQcelp13-tes
t
push: .\system/bin/mm-adec-omxmp3-test -> /system/bin/mm-adec-omxmp3-test
push: .\system/bin/mm-adec-omxevrc-test -> /system/bin/mm-adec-omxevrc-test
push: .\system/bin/mm-adec-omxamrwb-test -> /system/bin/mm-adec-omxamrwb-test
push: .\system/bin/mm-adec-omxamr-test -> /system/bin/mm-adec-omxamr-test
push: .\system/bin/mm-adec-omxaac-test -> /system/bin/mm-adec-omxaac-test
push: .\system/bin/mm-abl-test -> /system/bin/mm-abl-test
push: .\system/bin/mke2fs -> /system/bin/mke2fs
push: .\system/bin/mkdir -> /system/bin/mkdir
push: .\system/bin/mediaserver -> /system/bin/mediaserver
push: .\system/bin/lsmod -> /system/bin/lsmod
push: .\system/bin/ls -> /system/bin/ls
push: .\system/bin/logwrapper -> /system/bin/logwrapper
push: .\system/bin/logcat -> /system/bin/logcat
push: .\system/bin/log -> /system/bin/log
push: .\system/bin/loc_api_app -> /system/bin/loc_api_app
push: .\system/bin/ln -> /system/bin/ln
push: .\system/bin/linker -> /system/bin/linker
push: .\system/bin/kill -> /system/bin/kill
push: .\system/bin/keystore -> /system/bin/keystore
push: .\system/bin/jrd_rapiproxy -> /system/bin/jrd_rapiproxy
push: .\system/bin/jrd_diag -> /system/bin/jrd_diag
push: .\system/bin/jrdput -> /system/bin/jrdput
push: .\system/bin/ip -> /system/bin/ip
push: .\system/bin/ioctl -> /system/bin/ioctl
push: .\system/bin/installd -> /system/bin/installd
push: .\system/bin/insmod -> /system/bin/insmod
push: .\system/bin/input -> /system/bin/input
push: .\system/bin/ime -> /system/bin/ime
push: .\system/bin/iftop -> /system/bin/iftop
push: .\system/bin/ifconfig -> /system/bin/ifconfig
push: .\system/bin/id -> /system/bin/id
push: .\system/bin/hd -> /system/bin/hd
push: .\system/bin/hci_qcomm_init -> /system/bin/hci_qcomm_init
push: .\system/bin/hciattach -> /system/bin/hciattach
push: .\system/bin/handset-keypress -> /system/bin/handset-keypress
push: .\system/bin/gzip -> /system/bin/gzip
push: .\system/bin/getprop -> /system/bin/getprop
push: .\system/bin/getevent -> /system/bin/getevent
push: .\system/bin/fsck_msdos -> /system/bin/fsck_msdos
push: .\system/bin/fm_qsoc_patches -> /system/bin/fm_qsoc_patches
// got stuck here