Messages in this thread | | | Date | Wed, 7 Feb 2007 12:35:52 +0000 | From | Pavel Machek <> | Subject | Re: [PATCH 9/11] Panic delay fix |
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Hi! > > > >>Failure to use real-time delay here causes the > >>keyboard to become demonically > >>possessed in the event of a kernel crash, with wildly > >>blinking lights and > >>unpredictable behavior. This has resulted in several > >>injuries. > > > >There must be a reason why it wasn't default before. > >Has this > >reason changed? > > This only matters under paravirt; non-paravirt kernels > and kernels running on native hardware will always > behave properly. > > But paravirtualized kernels with fake devices have no > need to udelay to accommodate slow hardware - the > hardware is just virtual. The USE_REAL_TIME_DELAY > define allows udelay to be specifically reverted back to > being a real delay. There are only a couple cases where
Ugh, it sounds like paravirt is more b0rken then I thought. It should always to the proper delay, then replace those udelays that are not needed on virtualized hardware with something else.
Just magically defining udelay into nop is broken.
Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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