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[Q] Emmc Boot Recovery Misc Partition JY-G2 MTK6577

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I got a cheap chinese phone Jiayu G2+ (MTK6577) model and I'm trying to learn the partitions of this device. I guess it doesn't help that I'm just starting to learn the inner workings of android in general. Trying to port CWM / TWRP to this phone. I've managed to done some of this work with the help of the BGCNGM's unpacker scripts, unfortunately, CWM isn't reading some partitions correctly so it's unable to perform nandroid backup and gets stuck at "backing up boot image".

It doesn't look like the device uses MTD, get empty when I go cat /proc/mtd
so when I executed cat /proc/partitions, this is what i get

Code:

major      minor  #blocks      name

179        0      3792000      mmcblk0
179        1      1            mmcblk0p1   
179        2      5120        mmcblk0p2 
179        3      524288      mmcblk0p3   
179        4      524288      mmcblk0p4   
179        5      2661376      mmcblk0p5 
179        6      45280        mmcblk0p6
179      64      1024        mmcblk0boot1
179      32      1024        mmcblk0boot0
179      96      15637504    mmcblk1
179      97      15636480    mmcblk1p1

It looks like mmcblk1 is my 16GB microsd card.

Doing a ls -la in my root directory, I can find the mapps of mmcblk0
Code:

emmc@ebr1 -> /dev/block/mmcblk0p1
emmc@sec_ro -> /dev/block/mmcblk0p2
emmc@android -> /dev/block/mmcblk0p3
emmc@cache -> /dev/block/mmcblk0p4
emmc@usrdata -> /dev/block/mmcblk0p5
emmc@fat -> /dev/block/mmcblk0p6

So what's left is mmcblk0boot1 and mmcblk0boot2, logical guess is that these are boot related partitions. But not exactly sure how to read these though.

Here's a copy of the recovery.fstab from the original rom's recovery.img
Code:

# mount point  fstype          device                  [device2]

/boot          emmc            boot
/cache          ext4            /dev/block/mmcblk0p4
/data          ext4            /dev/block/mmcblk0p5
/misc          emmc            misc
/recovery      emmc            recovery
/sdcard        vfat            /dev/block/mmcblk0p6
/sdcard2        vfat            /dev/block/mmcblk1p1
/system        ext4            /dev/block/mmcblk0p3

As I mentioned earlier, I'm unable to perform CWM backup most likely because CWM can't find the boot, misc, and recovery.
1. Does anyone have any idea how I can find these partitions?
2. So it looks like my /system partition (lives under 512mb partition /dev/block/mmcblk0p3) whenever I do a dd export of system.img, the file IS 512mb. But when I flash the rom using SP Flash Tool, the original firmware image for system.img is around 200 megs. So I'm assuming this is a full partition copy? Is there anyway I can export this without the dead space? Looking into ROM development.

Thanks for any tips and guides.

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