On Fri, Feb 27, 2009 at 5:51 PM, Jeremy Fitzhardinge <jeremy@xxxxxxxx> wrote:
From: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>...
Rather than having special purpose init_pg_table_start/end variables
to delimit the kernel pagetable built by head_32.S, just use the brk
mechanism to extend the bss for the new pagetable.
This patch removes init_pg_table_start/end and pg0, defines __brk_base
(which is page-aligned and immediately follows _end), initializes
the brk region to start there, and uses it for the 32-bit pagetable.
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index c246dc4..ed02176 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -113,8 +113,10 @@
#endif
unsigned int boot_cpu_id __read_mostly;
-__initdata unsigned long _brk_start = (unsigned long)&_end;
-__initdata unsigned long _brk_end = (unsigned long)&_end;
+
+extern char __brk_base[];
+__initdata unsigned long _brk_start = (unsigned long)__brk_base;
+__initdata unsigned long _brk_end = (unsigned long)&__brk_base;
?