Hardware RTC device is deregistered immediately after detection
Issue
The hardware clock is not operable with the hwclock utility. The kernel ring buffer contains the following messages:
WARNING: at arch/x86/kernel/rtc.c:125 mach_get_cmos_time+0x175/0x190() (Not tainted)
rtc_cmos 00:0a: RTC can wake from S4
rtc_cmos 00:0a: rtc core: registered rtc_cmos as rtc0
drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
which means that the RTC device was detected, but then was immediately deregistered.
Environment
- Red Hat Enterprise Linux
- RTC device, that does not support 24-hr BCD mode
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