On Fri, 2006-03-31 at 16:35 +0200, Jurgen Kramer wrote: > 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. Actually the message will only get displayed on i386 kernels, not on x86_64 kernels (running on both AMD and Intel platforms) I'd assume that the reasoning for dropping the printk's on x86_64 is simple: NX on i386 is pretty much limited to rather recent machines; all/most pure i386 CPU core do not support it. OTOH, most x86_64 CPU core support NX out of the box. To cut a long story short... if you're on x86_64, you most likely have NX. No need to say/display/printk anything about it. > > Thanks. > > Jurgen > > Gilboa
