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SubjectRe: [kerneloops] regression in 2.6.27 wrt "lock_page" and the "hwclock" program
On Mon, Oct 13, 2008 at 10:55:59AM -0400, Arjan van de Ven wrote:
> Karel: Can you describe what it WANTS to do so we can see if we can

It wants to "atomically" (without context switch) read/write time
from CMOS. This is unrealistic of course.

> just extend the linux kernel to do that the right way?

The kernel is already extended and hwclock uses the extension :-)
The solution is /dev/rtc.

The code that directly works with CMOS is fallback solution for
people who don't want or can not use the standard RTC device. I guess
people use this functionally for experiments only. Today the RTC
framework should work everywhere.

I'll simply remove the "cli" / "sti" code -- eventually I can try
to optimize it by mlockall() and SCHED_FIFO (as suggested by Linus).

Karel

--
Karel Zak <kzak@redhat.com>


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