[One (M7) General] ian.anindya:
To summarized on what have been done on HTC One M7/8 AT&T to modified NV Item.

Tool PC, USB cable, QPST and QXDM

1. From JB stock rom to Lollipop stock---> Failed to write/change NV value. NV value remain the same from JB ROM to LL Rom.

2. Move to other region WWE Rom with different band on that region-----> NV value keep the same as original AT&T (flash other RUU doesn't give any impact).

3. Play with many custom rom (JB-LL), CM, SD, HD, Insert coin with many other custom kernel ----> Failed to write/change NV value. NV value remain the same AT&T stock rom.

Clues...

Rom level (negative)

Firmware level (negative).

Kernel level (negative).

1. [suspect] there is security code that need to push to unlock "read only mode".

2. [suspect] Different Qualcomm software to modified NV value (nor QPST or QXDM or latest version of both - build 2014/15).

3. [suspect] Lower level flashing MSM chip technic like JTAG lavel but for chip modem MSM?

4. [suspect] Engineering cable (HS-USB) or other type with combination latest Qualcomm software..??

To be continue...

---------- Post added at 11:53 PM ---------- Previous post was at 11:18 PM ----------

Other clue that perhaps we can disable write security by one of below command:

C:\ADB>fastboot oem ?

...

(bootloader) #. <command> : <brief description>

(bootloader) security_emmc_command:

(bootloader) 1. check_emmc_mid : no desc.

(bootloader) 2. get_sector_info_emmc : no desc.

(bootloader) security_command:

(bootloader) 1. boot : no desc.

(bootloader) 2. sensorhubflash : no desc.

(bootloader) 3. cirfwflash : no desc.

(bootloader) 4. clearaspflag : no desc.

(bootloader) 5. erase_phone_storage : no desc.

(bootloader) 6. eraseconfig : no desc.

(bootloader) 7. battinfo : no desc.

(bootloader) 8. gotohboot : no desc.

(bootloader) 9. heap_test : no desc.

(bootloader) 10. heap : no desc.

(bootloader) 11. keytest : no desc.

(bootloader) 12. powerdown : no desc.

(bootloader) 13. readcid : no desc.

(bootloader) 14. readconfig : no desc.

(bootloader) 15. readimei : no desc.

(bootloader) 16. readimei2 : no desc.

(bootloader) 17. readmeid : no desc.

(bootloader) 18. readpid : no desc.

(bootloader) 19. readsecureflag : no desc.

(bootloader) 20. rebootRUU : no desc.

(bootloader) 21. refurbish : no desc.

(bootloader) 22. copyFotaBoot : no desc.

(bootloader) 23. reset : no desc.

(bootloader) 24. resetgift : no desc.

(bootloader) 25. resethtcdebugflag : no desc.

(bootloader) 26. task : no desc.

(bootloader) 27. writecid : no desc.

(bootloader) 28. writeimei : no desc.

(bootloader) 29. writeimei2 : no desc.

(bootloader) 30. writemeid : no desc.

(bootloader) 31. writepid : no desc.

(bootloader) 32. writesecureflag : no desc.

(bootloader) 33. dsiw : no desc.

(bootloader) 34. dsir : no desc.

(bootloader) 35. clear_atsdebug : no desc.

(bootloader) 36. read_atsdebug : no desc.

(bootloader) 37. dmesg : no desc.

(bootloader) 38. last_dmesg : no desc.

(bootloader) 39. get_identifier_token : no desc.

(bootloader) 40. checkKeycardID : no desc.

(bootloader) 41. readusername : no desc.

(bootloader) 42. writeusername : no desc.

(bootloader) 43. get_tamper_flag : no desc.

(bootloader) 44. get_force_sec_boot_reason: no desc.

(bootloader) 45. checkHWSecurity : no desc.

(bootloader) 46. checkSbl1 : no desc.

(bootloader) 47. pmic8941_led_test : no desc.

(bootloader) 48. MRW : no desc.

(bootloader) 49. MRR : no desc.

(bootloader) 50. off-mode-charge : no desc.

(bootloader) 51. readredeemrecord : no desc.

(bootloader) chipset_security_command:

(bootloader) 1. erase_nfc_record : no desc.

(bootloader) 2. felicacal : no desc.

(bootloader) 3. felicasetparam_secure : no desc.

(bootloader) 4. felicagetparam_secure : no desc.

(bootloader) 5. felicaponhigh_secure : no desc.

(bootloader) 6. felicaponlow_secure : no desc.

(bootloader) 7. lock : no desc.

(bootloader) 8. ats : no desc.

(bootloader) 9. ddr2gbh : no desc.

(bootloader) 10. ddr2gstatus : no desc.

(bootloader) 11. enableqxdm : no desc.

(bootloader) 12. gencheckpt : no desc.

(bootloader) 13. get_temp : no desc.

(bootloader) 14. ramdump2gbh : no desc.

(bootloader) 15. rtask : no desc.

(bootloader) 16. validateimeihash : no desc.

(bootloader) 17. to_sbldload : no desc.

(bootloader) m8_command:

(bootloader) 1. gpiomap : list all gpio mapping (normal

(bootloader) ized # / physical gpio pin# / validity)

OKAY [ 0.297s]

finished. total time: 0.297s