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| author | kib <kib@FreeBSD.org> | 2015-04-27 08:02:12 +0000 |
|---|---|---|
| committer | kib <kib@FreeBSD.org> | 2015-04-27 08:02:12 +0000 |
| commit | facaa68fb95e65d46783aee588e7c99ae11d5e76 (patch) | |
| tree | 2490a68d0f0407f65b7522b1e69ee07cc835dfe8 /sys/conf | |
| parent | bc0b39657e72b1c736b37854e76ac5d962c82641 (diff) | |
| download | FreeBSD-src-facaa68fb95e65d46783aee588e7c99ae11d5e76.zip FreeBSD-src-facaa68fb95e65d46783aee588e7c99ae11d5e76.tar.gz | |
MFC r281495:
Add config option PAE_TABLES for the i386 kernel. It switches pmap to
use PAE format for the page tables, but does not incur other
consequences of the full PAE config. In particular, vm_paddr_t and
bus_addr_t are left 32bit, and max supported memory is still limited
by 4GB.
The option allows to have nx permissions for memory mappings on i386
kernel, while keeping the usual i386 KBI and avoiding the kernel data
sizing problems typical for the PAE config.
Diffstat (limited to 'sys/conf')
| -rw-r--r-- | sys/conf/options.i386 | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/sys/conf/options.i386 b/sys/conf/options.i386 index 7e64a80..7102d8f 100644 --- a/sys/conf/options.i386 +++ b/sys/conf/options.i386 @@ -37,6 +37,11 @@ KVA_PAGES opt_global.h # Physical address extensions and support for >4G ram. As above. PAE opt_global.h +# Use PAE page tables, but limit memory support to 4GB. +# This keeps the i386 non-PAE KBI, in particular, drivers see +# 32bit vm_paddr_t. +PAE_TABLES opt_global.h + TIMER_FREQ opt_clock.h CPU_ATHLON_SSE_HACK opt_cpu.h |
