lkml.org 
[lkml]   [2000]   [Oct]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: missing mxcsr initialization
Date
Followup to:  <39F77A0F.BA1422C9@redhat.com>
By author: Doug Ledford <dledford@redhat.com>
In newsgroup: linux.dev.kernel
>
> On that specific bit I haven't seen it go out of sync yet. However, I program
> it defensively because I already got bit by the fact that the X86_FEATURE_PN
> bit on Intel means something different than on AMD and as a result of getting
> it wrong my first time out, AMD CPUs were segfaulting when I tried to disable
> their non-existent serial number. So, since these bits vary from vendor to
> vendor, I would prefer to see it handled like the PN bit, that is check for
> all vendors that *do* use the bit to mean FXSR or XMM, but don't rely on all
> vendors to do so. In that case, we could check for vendor == INTEL || vendor
> == AMD, but I would still prefer to see *some* check on the vendor before
> honoring the bits.
>

This isn't defensive programming at all. You *introduce* bugs this
way; instead of handling (CPU) bugs as the workarounds they are.

-hpa
--
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:43    [W:0.085 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site