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SubjectRe: Using >1GB RAM
Hello!

In article <Pine.LNX.3.95.980113215041.23894A-100000@nightshade.z.ml.org> you write:
>[...]
>Any datapoints on how other X86 OSes handle this?

OpenBSD doesn't map the whole real memory into its kernel virtual
address space. The kernel virtual addresses range from

/* KPTDI<<PDSHIFT */
#define VM_MIN_KERNEL_ADDRESS ((vm_offset_t)0xf0000000)
to

/* APTDPTDI<<PDSHIFT */
#define VM_MAX_KERNEL_ADDRESS ((vm_offset_t)0xffc00000)
making up for a maximum of 0xfc (252) megabytes of kernel virtual address
space. Access to physical memory (for /dev/mem or paging) is done
using temporary mappings.

Regards, Felix.

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