linux-kernel - 2.6 kernels wrongly declare "fdiv

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Date:	Mon, 7 Dec 2009 21:01:32 -0500
From:	ZB <zbigniewbrzezinskix@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: 2.6 kernels wrongly declare "fdiv_bug: no"

/proc/cpuinfo fdiv_bug says "no" in 2.6.32 and other 2.6 kernels,
but 2.4 kernels say "yes" as does the Intel utility

2.4.37:
Intel Pentium with F0 0F bug - workaround enabled.
CPU: Intel Pentium 75 - 200 stepping 01
Hmm, FPU with FDIV bug.
Checking 'hlt' instruction... OK.

processor	: 0
vendor_id	: GenuineIntel
cpu family	: 5
model		: 2
model name	: Pentium 75 - 200
stepping	: 1
cpu MHz		: 90.205
fdiv_bug	: yes
hlt_bug		: no
f00f_bug	: yes
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 1
wp		: yes
flags		: fpu vme de pse tsc msr mce cx8
bogomips	: 179.81


2.6.32:
Intel Pentium with F0 0F bug - workaround enabled.
[blank line here]
CPU: Intel Pentium 75 - 200 stepping 01
Checking 'hlt' instruction... OK.

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 5
model           : 2
model name      : Pentium 75 - 200
stepping        : 1
cpu MHz         : 90.199
cache size      : 0 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : yes
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu vme de pse tsc msr mce cx8
bogomips        : 180.91
clflush size    : 32
cache_alignment : 32
address sizes   : 32 bits physical, 32 bits virtual
power management:
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