Unable to login to root

[jyijyi]

i wonder if you really do a factory reset successfully…

Do you have UART console?
you can see here to use flash_eraseall command:

Swiflash -r broken with release 12 on wp77xx?

According to the release note of fw r12, QTI9X07-2870 is to fix userapp partition being erased which is security hole. You might also try the following without downgrading to older version: (Be careful of the mtd number, different FW might have different mtd number for userapp partition !!! ) root@swi-mdm9x28-wp:~# cat /proc/mtd|grep userapp -i mtd16: 08300000 00040000 "userapp" root@swi-mdm9x28-wp:~# pwd /home/root root@swi-mdm9x28-wp:~# ls UART_Test1.wp77xx.update root@swi-mdm9x28-wp:~# fl…