Public bug reported: (originally asked over at askubuntu.com, but is still unresolved: https://askubuntu.com/questions/971349/problem-with-real-time-clock- since-upgrading-to-ubuntu-17-10)
I recently upgraded from Ubuntu 17.04 to Ubuntu 17.10 using the software update process. The update completed without any errors, and Ubuntu 17.10 is now running without any major issues. However, I was running a script previously that uses rtcwake which has since stopped working. The script automatically hibernates my laptop after a set period of time in sleep mode, and was working perfectly in Ubuntu 17.04. In the process of troubleshooting, I discovered that the problem was with rtcwake which is complaining about /dev/rtc0 missing. Here is output from a sample rtcwake command: peter@haven:~$ rtcwake -m no -s 1300 rtcwake: assuming RTC uses UTC ... rtcwake: /dev/rtc0: unable to find device: No such file or directory I verified that in fact, that directory is missing. Since this was working prior to the upgrade, I have to assume that it was there previously, but I don't know for sure. In researching the error, I found some suggestions to get further information with timedatectl and hwclock, so here are the results from those commands as well. Output of timedatectl: peter@haven:~$ timedatectl Local time: Fri 2017-10-27 19:06:26 EDT Universal time: Fri 2017-10-27 23:06:26 UTC RTC time: n/a Time zone: America/New_York (EDT, -0400) Network time on: yes NTP synchronized: yes RTC in local TZ: no Output of hwclock --debug: peter@haven:~$ sudo hwclock --debug [sudo] password for peter: hwclock from util-linux 2.30.1 Trying to open: /dev/rtc0 Trying to open: /dev/rtc Trying to open: /dev/misc/rtc No usable clock interface found. hwclock: Cannot access the Hardware Clock via any known method. UPDATE When I boot with my old kernel, 4.10.0-37-generic the real-time clock works fine. I get the following RTC messages in dmesg when I boot the 4.13.0-16-generic kernel: peter@haven:~$ dmesg | grep -i rtc [ 0.089393] RTC time: 17:03:55, date: 11/01/17 [ 1.238784] rtc_cmos 00:01: RTC can wake from S4 [ 1.238794] rtc_cmos: probe of 00:01 failed with error -16 [ 1.295459] hctosys: unable to open rtc device (rtc0) UPDATE #2 Well, I was starting to believe that I had a hardware issue, since discovering I was unable to save changes to my BIOS and could not boot from USB. As it turns out, my laptop was bitten by this bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1734147 causing my BIOS to be locked in a read-only state. Once I resolved the BIOS issue, and fixed the USB boot problem, I did a live boot of Ubuntu 17.10. The issue with my real time clock still exists under this clean boot scenario, yet when I boot other distros, like Linux Mint 18.3 and the real time clock works fine. I feel this definitely has something to do with the Ubuntu install, perhaps even a kernel bug. UPDATE #3 More evidence to suggest this is a kernel bug: I live-booted a copy of Antergos Linux, which was using the Arch kernel 4.14.12-1-ARCH and it exhibited the same problem with the real time clock as Ubuntu 17.10. In addition, I confirmed that the Linux Mint version I booted earlier (see Update #2) was on the Ubuntu kernel 4.10.0-38-generic. So, I suspect that sometime between kernels 4.10 and 4.13 this bug was introduced. ** Affects: compiz-plugins-main (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of DX Packages, which is subscribed to compiz-plugins-main in Ubuntu. Matching subscriptions: dx-packages https://bugs.launchpad.net/bugs/1743027 Title: error loading realtime clock since upgrading to 17.10 Status in compiz-plugins-main package in Ubuntu: New Bug description: (originally asked over at askubuntu.com, but is still unresolved: https://askubuntu.com/questions/971349/problem-with-real-time-clock- since-upgrading-to-ubuntu-17-10) I recently upgraded from Ubuntu 17.04 to Ubuntu 17.10 using the software update process. The update completed without any errors, and Ubuntu 17.10 is now running without any major issues. However, I was running a script previously that uses rtcwake which has since stopped working. The script automatically hibernates my laptop after a set period of time in sleep mode, and was working perfectly in Ubuntu 17.04. In the process of troubleshooting, I discovered that the problem was with rtcwake which is complaining about /dev/rtc0 missing. Here is output from a sample rtcwake command: peter@haven:~$ rtcwake -m no -s 1300 rtcwake: assuming RTC uses UTC ... rtcwake: /dev/rtc0: unable to find device: No such file or directory I verified that in fact, that directory is missing. Since this was working prior to the upgrade, I have to assume that it was there previously, but I don't know for sure. In researching the error, I found some suggestions to get further information with timedatectl and hwclock, so here are the results from those commands as well. Output of timedatectl: peter@haven:~$ timedatectl Local time: Fri 2017-10-27 19:06:26 EDT Universal time: Fri 2017-10-27 23:06:26 UTC RTC time: n/a Time zone: America/New_York (EDT, -0400) Network time on: yes NTP synchronized: yes RTC in local TZ: no Output of hwclock --debug: peter@haven:~$ sudo hwclock --debug [sudo] password for peter: hwclock from util-linux 2.30.1 Trying to open: /dev/rtc0 Trying to open: /dev/rtc Trying to open: /dev/misc/rtc No usable clock interface found. hwclock: Cannot access the Hardware Clock via any known method. UPDATE When I boot with my old kernel, 4.10.0-37-generic the real-time clock works fine. I get the following RTC messages in dmesg when I boot the 4.13.0-16-generic kernel: peter@haven:~$ dmesg | grep -i rtc [ 0.089393] RTC time: 17:03:55, date: 11/01/17 [ 1.238784] rtc_cmos 00:01: RTC can wake from S4 [ 1.238794] rtc_cmos: probe of 00:01 failed with error -16 [ 1.295459] hctosys: unable to open rtc device (rtc0) UPDATE #2 Well, I was starting to believe that I had a hardware issue, since discovering I was unable to save changes to my BIOS and could not boot from USB. As it turns out, my laptop was bitten by this bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1734147 causing my BIOS to be locked in a read-only state. Once I resolved the BIOS issue, and fixed the USB boot problem, I did a live boot of Ubuntu 17.10. The issue with my real time clock still exists under this clean boot scenario, yet when I boot other distros, like Linux Mint 18.3 and the real time clock works fine. I feel this definitely has something to do with the Ubuntu install, perhaps even a kernel bug. UPDATE #3 More evidence to suggest this is a kernel bug: I live-booted a copy of Antergos Linux, which was using the Arch kernel 4.14.12-1-ARCH and it exhibited the same problem with the real time clock as Ubuntu 17.10. In addition, I confirmed that the Linux Mint version I booted earlier (see Update #2) was on the Ubuntu kernel 4.10.0-38-generic. So, I suspect that sometime between kernels 4.10 and 4.13 this bug was introduced. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/compiz-plugins-main/+bug/1743027/+subscriptions -- Mailing list: https://launchpad.net/~dx-packages Post to : dx-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~dx-packages More help : https://help.launchpad.net/ListHelp