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This driver causes hard lockups, when the active clock soure is jiffies. The reason is that it loops with interrupts disabled waiting for a timestamp to be reached by polling getnstimeofday(). Though with a jiffies clocksource, when that code runs on the same CPU which is responsible for updating jiffies, then we loop in circles for ever simply because the timer interrupt cannot update jiffies. So both UP and SMP can be affected. There is no easy fix for that problem so make it depend on BROKEN for now. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Gordeev <lasaine@lvk.cs.msu.su> Cc: Rodolfo Giometti <giometti@linux.it> Cc: john stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
13 lines
400 B
Text
13 lines
400 B
Text
#
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# PPS generators configuration
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#
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comment "PPS generators support"
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config PPS_GENERATOR_PARPORT
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tristate "Parallel port PPS signal generator"
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depends on PARPORT && BROKEN
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help
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If you say yes here you get support for a PPS signal generator which
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utilizes STROBE pin of a parallel port to send PPS signals. It uses
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parport abstraction layer and hrtimers to precisely control the signal.
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