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I just finished installing a paravirtualized archlinux guest on xen. I get the following error when my guest boots:

[1.185226] i8042: No controller found [1.1247134] drivers/rtc/hctosys.c: unable to open rtc device (rtc0)

After it displays this the computer asks me to login as normal.

Google told me this is the driver for the hardware clock so I tried the following:

[root@coronelaurelianobuendia ~]# hwclock --systohc --utc  
hwclock: Cannot access the Hardware Clock via any known method.  
hwclock: Use the --debug option to see the details of our search for an access

[root@coronelaurelianobuendia ~]# hwclock --debug 
hwclock from util-linux 2.24  
hwclock: cannot open /dev/rtc: No such file or directory No usable clock 
interface found.   
hwclock: Cannot access the Hardware Clock via any known method.

Is this a problem with my grub.cfg? A problem with PV arch? Or a problem with my kernel?

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Okay, after extensive research, recompiling my kernel, and creating another guest just to test this I conclude:

The boot error is completely normal and can be safely ignored.

In xen, the guest's clocks are synced to the domain0 hwclock and cannot normally be changed. All domUs will say "no usable clock found."

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