My dmesg and syslog and kernel log are loaded with messages like this, which seems to imply some component failed.

Oct 13 13:21:19 nanopit41 rsyslogd-2007: action 'action 9' suspended, next retry is Sat Oct 13 13:22:49 2018 [v8.16.0 try http://www.rsyslog.com/e/2007 ]
Oct 13 13:40:22 nanopit41 kernel: [2828447.981396] dwmmc_rockchip fe310000.dwmmc: All phases bad!
Oct 13 13:40:22 nanopit41 kernel: [2828447.981938] mmc2: tuning execution failed
Oct 13 13:40:22 nanopit41 kernel: [2828447.982510] bcmsdh_sdmmc: Failed to Read byte F1:@0x1001f=ff, Err: -5
Oct 13 13:40:22 nanopit41 rsyslogd-2007: action 'action 9' suspended, next retry is Sat Oct 13 13:41:52 2018 [v8.16.0 try http://www.rsyslog.com/e/2007 ]
Oct 13 13:40:22 nanopit41 kernel: [2828447.989341] dwmmc_rockchip fe310000.dwmmc: All phases bad!
Oct 13 13:40:22 nanopit41 kernel: [2828447.989872] mmc2: tuning execution failed
Oct 13 13:40:22 nanopit41 kernel: [2828447.990422] bcmsdh_sdmmc: Failed to Read byte F1:@0x1001f=ff, Err: -5
Oct 13 13:40:22 nanopit41 kernel: [2828447.996326] dwmmc_rockchip fe310000.dwmmc: All phases bad!
Oct 13 13:40:22 nanopit41 kernel: [2828447.996853] mmc2: tuning execution failed
Oct 13 13:40:22 nanopit41 kernel: [2828447.997463] bcmsdh_sdmmc: Failed to Write byte F1:@0x1001f=00, Err: -5
Oct 13 13:40:22 nanopit41 kernel: [2828448.002731] dwmmc_rockchip fe310000.dwmmc: All phases bad!
Oct 13 13:40:22 nanopit41 kernel: [2828448.003286] mmc2: tuning execution failed
Oct 13 13:40:22 nanopit41 kernel: [2828448.003689] bcmsdh_sdmmc: Failed to Write byte F1:@0x1001f=00, Err: -5


uname -a
Linux nanopit41 4.4.126 #178 SMP Tue May 29 15:20:06 CST 2018 aarch64 aarch64 aarch64 GNU/Linux

lsb_release -a
Distributor ID: Ubuntu
Description: Ubuntu 16.04 LTS
Release: 16.04
Codename: xenial

I do have a part plugged into the pci socket, but it is not configured to run.

I have not rebooted it recently, and am hesitant to do so until finding out something about what this error may mean. i'm not sure what else to supply.

I have the problem with a NanoPC-T4 board. It seems to be performing fine and has been up for 33 days, but I just happened to see this error.