Android users are in for some great news, as the new Fastboot update ported into the preview release of Android M patches up the "missing system.img" error that affected several users who tried flashing Google's Lollipop factory images with flash-all script.

Android M (preview release) users can also enjoy the privilege of using the optional bootloader parameter with Fastboot's reboot command for restarting the device and quickly launching back the bootloader screen.

The catch here is that the new syntax for reboot bootloader command is cleaner than the previous version as it permits the use of the more common adb syntax, adb reboot bootloader.

The Android community would definitely benefit with such simple yet powerful shortcuts added to the arsenal of Fastboot commands.

In addition, the new Fastboot update for Android M brings a new set of flashing commands that offer better control over when and what should be written, once the device is in locked or unlocked state:

  • flashing lock - locks the device. Prevents flashing partitions
  • flashing unlock - unlocks the device. Allows user to flash any partition except the ones that are related to bootloader
  • flashing lock_critical - Prevents flashing bootloader related partitions
  • flashing unlock_critical - Enables flashing bootloader related partitions
  • flashing get_unlock_ability - Queries bootloader to see if the device is unlocked

By enforcing certain restrictions on how a script may be executed while flashing ROMs, it is now possible to avoid hard bricks and unexpected boot loop issues due to errors while flashing a ROM.

Flashing a factory image ROM will no longer involve decompression of the entire image into RAM, before the actual data transfer is done to the device. This feature had earlier triggered unwanted memory leak issues, as the substantially larger system image exceeded the amount of available physical memory.

The memory issue that invariably triggered the "missing system.img" error is now gone, and it has been reportedly confirmed that this fix works absolutely fine on all major operating systems including Windows, Mac and Linux.

Interested Android M users may go ahead and download the latest fastboot and adb executables through the SDK Manager in the Platform Tools package that can be found under rev.23rc2 of the Preview Channel.

[Source: Elliott Hughes (Google+) via Android Police]