Messages in this thread | | | Date | Wed, 7 Feb 2007 09:58:57 -0500 | From | "Dmitry Torokhov" <> | Subject | Re: [PATCH 9/11] Panic delay fix |
| |
On 2/6/07, Zachary Amsden <zach@vmware.com> wrote: > Andi Kleen wrote: > > On Mon, Feb 05, 2007 at 07:53:30PM -0800, Zachary Amsden wrote: > > > >> 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 it > matters - one is booting APs on SMP systems (there is a real delay > before they come up), and one is any hardware that drives world > interacting devices - such as keyboard LEDs in a panic loop. >
I am confused - does i8042 talk to a virtual or real hardware here? In any case I think you need to fix kernel/panic.c to have proper (m)delay, not mess with i8042.
-- Dmitry - 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/
| |