如题，手上的R6S刷机了Ubuntu的系统固件，然后登录系统运行测试程序。但是在使用pi用户和root用户运行时结果差异很大。
运行在pi用户：
编码和解码测试用例均可用，使用 mpp_buffer_test 测试程序也未报异常。
运行在root用户：
编码器和解码测试用例均不可用，错误位置在mpp_init ，研究原因是在内存处理上出现了异常。使用mpp_buffer_test 测试内存buffer
管理，报以下错误
mpp_buffer_testmpp_buffer_test start with debug 0xf
mpp_ionscan /proc/device-tree for vpu_service return 0
mpp_ionscan /proc/device-tree for hevc_service return 0
mpp_ionAssertion n == 1 failed at find_dir_in_path:194
mpp_ionscan /proc/device-tree/rkvdec-ccu@fdc30000 for iommu_enabled return 0
mpp_ionAssertion n == 1 failed at find_dir_in_path:194
mpp_ionscan /proc/device-tree/rkvenc-ccu for iommu_enabled return 0
mpp_ionscan /proc/device-tree for vpu_combo return 0
mpp_ionscan /sys/kernel/debug/ion/heaps for vmalloc return -1
mpp_ionscan /sys/kernel/debug/ion/heaps for system-heap return -1
mpp_ioncan not find any hint from all possible devices
mpp_ionusing ion heap ION_HEAP_TYPE_CARVEOUT
mpp_buffergroup 1 mode 1 type 1 ops grp create
mpp_bufferleave
mpp_buffer_testmpp_buffer_test commit mode with unused status start
mpp_buffergroup 2 mode 0 type 1 ops grp create
mpp_bufferenter
mpp_bufferleave
mpp_bufferenter
mpp_ionion_ioctl c0204900 failed with code -1: Invalid argument
mpp_ionion_alloc failed ret -22
mpp_bufferfailed to create buffer with size 4096
mpp_bufferleave
mpp_buffer_testmpp_buffer_test get misc buffer failed ret -1
mpp_bufferenter
mpp_buffergroup 1 mode 1 type 1 ops grp release
mpp_buffergroup 1 mode 1 type 1 ops grp destroy
mpp_bufferleave
mpp_buffer_testmpp_buffer_test failed
mpp_buffercleaning misc group
mpp_buffergroup 2 mode 0 type 1 ops grp release
mpp_buffergroup 2 mode 0 type 1 ops grp destroy
