On Tuesday, May 03, 2011 9:10:26 am Philip Soeberg wrote:
> Hi fellow FreeBSD hackers,
>
> I've been using the following poor-man's approach in my driver init for
> ages in an attempt at detecting PAE option on BSD 6 (or greater) i386
> kernels, as I depend on dmabus(9) but provide a loadable kernel module only.
>
> >>>
> if (sizeof(void*) == 4) {
> if (((uint64_t)(cnt.v_page_count * cnt.v_page_size) / 1073741824)
> >= 4) {
> printf("FreeBSD i386 detected with PAE option enabled. FreeBSD
> PAE type\n");
> printf("kernels does not support loadable modules which use DMA.
> Please\n");
> printf("reconfigure your kernel for non-PAE or switch to amd64
> kernel.\n");
> return EFAULT;
> }
> }
> <<<
Hmmm, even this isn't really accurate as some folks may choose to enable PAE
even with < 4GB to get PG_NX functionality.
> afaik there's a sysctl method of checking this per BSD7 (or is it 8?),
> but what about BSD6? Any hints on how I can runtime detect the above?
Definitely a kern.features.pae sysctl in 7. I don't see anything similar in
6.
--
John Baldwin
_______________________________________________
freebsd-hackers@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
