On Fri, 2006-03-31 at 09:36 -0500, fedora-list-request(a)redhat.com wrote:
Date: Fri, 31 Mar 2006 16:35:55 +0200
From: Jurgen Kramer <gtm.kramer(a)inter.nl.net>
Subject: Re: NX bit: AMD vs Intel?
To: gilboad(a)gmail.com
Cc: For users of Fedora Core releases <fedora-list(a)redhat.com>
Message-ID: <1143815755.3328.10.camel(a)paragon.slim>
Content-Type: text/plain
On Fri, 2006-03-31 at 17:09 +0300, Gilboa Davara wrote:
> On Fri, 2006-03-31 at 12:56 +0200, Jurgen Kramer wrote:
> > On my Intel system (Xeon with EMT64 support) which runs the 32-bit
> > version of FC5 I can see that NX support is active (from dmesg):
> >
> > NX (Execute Disable) protection: active
> >
> > On my other system, a AMD64 system running the 64-bit version of FC4,
> > there is no message regarding NX support being enabled of disabled at
> > all.
> >
> > Checking init.c in the kernel sources it seems that NX support is
> > depended on PAE support and NX support from the processor. As the AMD
> > processor supports both I aspect to see a NX procection active message
> > on my AMD system as well. Does NX support suppose to work on 64-bit
> > kernels ?
> >
> > Both systems run kernel 2.6.16.
> >
> > Jurgen
> >
>
> AFAICS, It's activated quietly if present on iAMD64 systems.
> No printk code.
>
> So, if /proc/cpuinfo includes nx, you're in the clear.
>
Yep, nx is there. Odd that it is only displayed on Intel systems.
Thanks.
Jurgen
On my system I get the following:
cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 4
model name : AMD Athlon(tm) 64 Processor 2800+
stepping : 8
cpu MHz : 800.000
cache size : 512 KB
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext lm
3dnowext 3dnow lahf_lm
bogomips : 1730.73
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management: ts fid vid ttp
Notice I see nx in /proc/cpuinfo.
Run this command on your system to see if it shows up...
--
ed <ed(a)gurski.com>