To use the debug device I need to work through a port so I need
to call ioreamp or similar.  Since we are doing this very early
I chose to use a fixmap (because we are unlikely to free the mapping)
and because it is simple.  If we preallocate the fixmap pud and pmd
entries the existing fixmap codes works anytime from power up without
modifications or memory allocations.  So we don't need a special case.

---
 arch/x86_64/kernel/head.S |   11 ++++++++++-
 1 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S
index 2f65469..4004965 100644
--- a/arch/x86_64/kernel/head.S
+++ b/arch/x86_64/kernel/head.S
@@ -271,7 +271,16 @@ NEXT_PAGE(level3_kernel_pgt)
        .fill   510,8,0
        /* (2^48-(2*1024*1024*1024)-((2^39)*511))/(2^30) = 510 */
        .quad   phys_level2_kernel_pgt | 0x007
-       .fill   1,8,0
+       .quad   phys_level2_fixmap_pgt | 0x007
+
+NEXT_PAGE(level2_fixmap_pgt)
+       .fill   506,8,0
+       .quad   phys_level1_fixmap_pgt | 0x007
+       /* 8MB reserved for vsyscalls + a 2MB hole = 4 + 1 entries */
+       .fill   5,8,0
+
+NEXT_PAGE(level1_fixmap_pgt)
+       .fill   512,8,0
 
 NEXT_PAGE(level2_ident_pgt)
        /* 40MB for bootup.     */
-- 
1.4.2.rc3.g7e18e-dirty

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to