首先确定写入key，操作如下：
检查 /persist/data/sfs 目录下是否有key文件存在
adb shell ls -la /persist/data/sfs
做过key provision的机器重新写key，参照如下步骤：
1）烧userdebug版本，重新写key需要在userdebug版本上才能做
2）执行下面命令擦除rpmb分区
MODEL1:/ # qseecom_sample_client v smplap64 15 1
Note: Command line arguments do not belong to legacy test
---------------------------------------------------------------
WARNING!!! You are about to erase the entire RPMB partition.
----------------------------------------------------------------
Do you want to proceed (y/n)? y
RPMB partition erase completed
3）重启机器，检查机器处于lock状态和rpmb key已经provision
adb reboot bootloader
执行下面命令查看locked状态
fastboot oem lock
(bootloader) Device already : locked!
OKAY [ 0.006s]
Finished. Total time: 0.007s
执行下面命令，若返回-1表示已经provision过rpmb key
MODEL1:/ # qseecom_sample_client v smplap64 14 1
Note: Command line arguments do not belong to legacy test
-------------------------------------------------------
WARNING!!! You are about to provision the RPMB key.
This is a ONE time operation and CANNOT be reversed.
-------------------------------------------------------
0 -> Provision Production key
1 -> Provision Test key
2 -> Check RPMB key provision status
-------------------------------------------------------
Select an option to proceed: 1
RPMB key provisioning failed (-1)
4） 后面就可以进行attestation key provison了
adb push keybox.xml /data/local/tmp
adb shell LD_LIBRARY_PATH=/vendor/lib64/hw KmInstallKeybox /data/local/tmp/keybox.xml your_key_file_product_id true
5）在user版本上测试时注意不要刷persist image，因为attestation key是写在persist分区的。
widevine要用到的话，也得先合入。可以参考 kba-160918225319_3_how_to_integrate_widevine_on_android.pdf，Integrate Widevine - GMS Help.pdf等文档。
然后，绝大部分问题都是高通的问题……很多都是闭源的，无能为力。