Re: [Fastboot] [PATCH 1/3] stack overflow safe kdump(2.6.18-rc1-i386) - safe_smp_processor_id

From: Fernando Luis Vázquez Cao
Date: Tue Jul 11 2006 - 02:13:38 EST


Hi Keith!

On Tue, 2006-07-11 at 14:55 +1000, Keith Owens wrote:
> Fernando Luis =?ISO-8859-1?Q?V=E1zquez?= Cao (on Tue, 11 Jul 2006 13:21:01 +0900) wrote:
> >That is a good idea, but I have on concern. In mach-default by default
> >we use __send_IPI_shortcut (no_broadcast==0) instead of send_IPI_mask.
> >Is it always safe to ignore the no_broadcast setting? In other words,
> >can __send_IPI_shortcut be replaced by send_IPI_mask safely?
>
> It is always safe to use send_IPI_mask. It is not used by default
> because of concerns that send_IPI_mask may be slower than using a
> broadcast, although I do not know if anybody has measurements to back
> up that concern. OTOH I can guarantee that sending NMI as a broadcast
> has problems, it breaks some Dell Xeon servers[1]. My fix was to never
> broadcast NMI, from 2.6.18-rc1 NMI_VECTOR always uses a mask[2] and
> crash was changed accordingly[3].
>
> [1] http://marc.theaimsgroup.com/?t=114828920800003&r=1&w=2
> [2] http://marc.theaimsgroup.com/?t=115103727400006&r=1&w=2
> [3] http://marc.theaimsgroup.com/?t=115096703800003&r=1&w=2

Thank you for the links (I had forgotten about that thread) and
comments!
I prepared new patches and hopefully I got it right this time, Do they
look good this time (PATCH 4/4 in particular)?

Thank you in advance,

Fernando

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