[E 2015 Q&A, Help & Troubleshooting] MarckozZ:
This device was on 5.1 stock... as it is from AT&T, bootloader is locked. I can enter fastboot mode, so it is not bricked, but when I try to reflash the latest AT&T firmware available for this phone it keeps saying that prevalidation error and invalid piv signed system image, even though I have the exact same firmware that was running before the OTA dropped...

As the AT&T webpage for XT1527 states, this is the OTA I accepted on the device:

Release date: December 16, 2016

Android version: 5.1

Baseband version: M8916_2020602.05.03.21.07R

Build number: LPI23.29-18.9-6

File size: 48.38MB

System version: 23.211.6.en.US

But when I run the command mfastboot getvar all, the phone shows it has the LPI23.29-18.9-2 build number installed! So, something went wrong during the update that corrupted (I guess) the kernel, because the device can't boot up normally. Just stays as it was off. It can access fastboot mode via vol down + power buttons. Also, when you plug it to the wall charger, it shows the offline charging screen, with the big battery icon and everything...

So, should I wait for the official AT&T firmware image for this OTA? Since I cant flash anything on it because of that prevalidation error crap!

LOG OF THE PHONE

C:\XT1527>mfastboot getvar all

(bootloader) version: 0.5

(bootloader) version-bootloader: moto-msm8916-80.10

(bootloader) product: surnia

(bootloader) board: surnia

(bootloader) secure: yes

(bootloader) hwrev: 0x8300

(bootloader) radio: 0x1

(bootloader) emmc: 8GB Micron REV=06 PRV=12 TYPE=17

(bootloader) ram: 1024MB Elpida S8 SDRAM DIE=4Gb

(bootloader) cpu: MSM8916 ES1.0

(bootloader) serialno: TA3970BWQA

(bootloader) cid: 0x0001

(bootloader) channelid: 0x84

(bootloader) uid: A5D76A1500000000000000000000

(bootloader) securestate: locked

(bootloader) iswarrantyvoid: no

(bootloader) mot_sst: 0

(bootloader) max-download-size: 268435456

(bootloader) reason: Volume down key pressed

(bootloader) imei: Hidden ;)

(bootloader) meid:

(bootloader) date: 01-09-2016

(bootloader) sku: XT1527

(bootloader) iccid: 89014103278783002002

(bootloader) cust_md5:

(bootloader) max-sparse-size: 268435456

(bootloader) current-time: "Wed Dec 16 20: 0: 5 UTC 2015"

(bootloader) ro.build.fingerprint[0]: motorola/surnia_att/surnia_umts:5.

(bootloader) ro.build.fingerprint[1]: 1/LPIS23.29-18.9-2/2:user/release-

(bootloader) ro.build.fingerprint[2]: keys

(bootloader) ro.build.version.full[0]: Blur_Version.23.201.2.surnia_att.

(bootloader) ro.build.version.full[1]: att.en.US

(bootloader) ro.build.version.qcom[0]: AU_LINUX_ANDROID_LA.BR.1.1.3_RB1.

(bootloader) ro.build.version.qcom[1]: 05.00.02.032.013

(bootloader) version-baseband[0]: M8916_2020602.05.03.21.07R SURNIA_ATT_

(bootloader) version-baseband[1]: CUST

(bootloader) kernel.version[0]: Linux version 3.10.49-gf2d7a94 (hudsoncm

(bootloader) kernel.version[1]: [MENTION=387459]ilc[/MENTION]lbld52) (gcc version 4.8 (GCC) ) #1

(bootloader) kernel.version[2]: SMP PREEMPT Mon Mar 28 02:49:46 CDT 2016

(bootloader) sbl1.git: git=MBM-NG-V80.10-0-g8f1d925

(bootloader) rpm.git: git=MBM-NG-V80.10-0-g099cb06

(bootloader) tz.git: git=MBM-NG-V80.10-0-g434e28a

(bootloader) hyp.git: git=MBM-NG-V80.10-0-g434e28a

(bootloader) aboot.git: git=MBM-NG-V80.10-0-g43dddc5

(bootloader) partition-type:modem: raw

(bootloader) partition-type:sbl1: raw

(bootloader) partition-type:DDR: raw

(bootloader) partition-type:aboot: raw

(bootloader) partition-type:rpm: raw

(bootloader) partition-type:tz: raw

(bootloader) partition-type:hyp: raw

(bootloader) partition-type:utags: raw

(bootloader) partition-type:logs: raw

(bootloader) partition-type:sec: raw

(bootloader) partition-type:factorytune1: raw

(bootloader) partition-type:padA: raw

(bootloader) partition-type:metadata: raw

(bootloader) partition-type:abootBackup: raw

(bootloader) partition-type:rpmBackup: raw

(bootloader) partition-type:tzBackup: raw

(bootloader) partition-type:utagsBackup: raw

(bootloader) partition-type:hypBackup: raw

(bootloader) partition-type:padB: raw

(bootloader) partition-type:frp: raw

(bootloader) partition-type:modemst1: raw

(bootloader) partition-type:modemst2: raw

(bootloader) partition-type:hob: raw

(bootloader) partition-type:dhob: raw

(bootloader) partition-type:fsg: raw

(bootloader) partition-type:fsc: raw

(bootloader) partition-type:ssd: raw

(bootloader) partition-type:cid: raw

(bootloader) partition-type:logo: raw

(bootloader) partition-type:clogo: raw

(bootloader) partition-type:persist: raw

(bootloader) partition-type:misc: raw

(bootloader) partition-type:boot: raw

(bootloader) partition-type:recovery: raw

(bootloader) partition-type:factorytune2: raw

(bootloader) partition-type:kpan: raw

(bootloader) partition-type:padC: raw

(bootloader) partition-type:sp: raw

(bootloader) partition-type:keystore: raw

(bootloader) partition-type:oem: raw

(bootloader) partition-type:carrier: ext4

(bootloader) partition-type:system: raw

(bootloader) partition-type:cache: raw

(bootloader) partition-type:userdata: raw

(bootloader) partition-size:modem: 0x0000000004000000

(bootloader) partition-size:sbl1: 0x0000000000080000

(bootloader) partition-size:DDR: 0x0000000000008000

(bootloader) partition-size:aboot: 0x0000000000100000

(bootloader) partition-size:rpm: 0x000000000003e800

(bootloader) partition-size:tz: 0x000000000007d000

(bootloader) partition-size:hyp: 0x0000000000020000

(bootloader) partition-size:utags: 0x0000000000080000

(bootloader) partition-size:logs: 0x0000000000200000

(bootloader) partition-size:sec: 0x0000000000004000

(bootloader) partition-size:factorytune1: 0x0000000000371000

(bootloader) partition-size:padA: 0x00000000001af000

(bootloader) partition-size:metadata: 0x0000000000080000

(bootloader) partition-size:abootBackup: 0x0000000000100000

(bootloader) partition-size:rpmBackup: 0x000000000003e800

(bootloader) partition-size:tzBackup: 0x000000000007d000

(bootloader) partition-size:utagsBackup: 0x0000000000080000

(bootloader) partition-size:hypBackup: 0x0000000000020000

(bootloader) partition-size:padB: 0x000000000048f000

(bootloader) partition-size:frp: 0x0000000000080000

(bootloader) partition-size:modemst1: 0x0000000000180000

(bootloader) partition-size:modemst2: 0x0000000000180000

(bootloader) partition-size:hob: 0x000000000007a000

(bootloader) partition-size:dhob: 0x0000000000008000

(bootloader) partition-size:fsg: 0x0000000000180000

(bootloader) partition-size:fsc: 0x0000000000000400

(bootloader) partition-size:ssd: 0x0000000000002000

(bootloader) partition-size:cid: 0x0000000000020000

(bootloader) partition-size:logo: 0x0000000000400000

(bootloader) partition-size:clogo: 0x0000000000400000

(bootloader) partition-size:persist: 0x0000000000800000

(bootloader) partition-size:misc: 0x0000000000080000

(bootloader) partition-size:boot: 0x0000000002000000

(bootloader) partition-size:recovery: 0x0000000001ffc000

(bootloader) partition-size:factorytune2: 0x0000000000a0e000

(bootloader) partition-size:kpan: 0x0000000000800000

(bootloader) partition-size:padC: 0x0000000000380000

(bootloader) partition-size:sp: 0x0000000001000000

(bootloader) partition-size:keystore: 0x0000000001000000

(bootloader) partition-size:oem: 0x0000000001000000

(bootloader) partition-size:carrier: 0x0000000001000000

(bootloader) partition-size:system: 0x0000000071000000

(bootloader) partition-size:cache: 0x0000000010000000

(bootloader) partition-size:userdata: 0x000000013ffe0000

(bootloader) qe: qe 0/0

(bootloader) ro.carrier: att

all: listed above

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