|author||H. Peter Anvin <firstname.lastname@example.org>||2007-07-11 12:18:33 -0700|
|committer||Linus Torvalds <email@example.com>||2007-07-12 10:55:54 -0700|
Define zero-page offset 0x1e4 as a scratch field, and use it
The relocatable kernel code needs a scratch field for the decompressor to determine its own location. It was using a location inside struct screen_info; reserve a free location and document it as scratch instead. Signed-off-by: H. Peter Anvin <firstname.lastname@example.org> Signed-off-by: Linus Torvalds <email@example.com>
Diffstat (limited to 'arch/x86_64')
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86_64/boot/compressed/head.S b/arch/x86_64/boot/compressed/head.S
index f9d5692a010..1312bfaff30 100644
@@ -46,10 +46,10 @@ startup_32:
* at and where we were actually loaded at. This can only be done
* with a short local call on x86. Nothing else will tell us what
* address we are running at. The reserved chunk of the real-mode
- * data at 0x34-0x3f are used as the stack for this calculation.
- * Only 4 bytes are needed.
+ * data at 0x1e4 (defined as a scratch field) are used as the stack
+ * for this calculation. Only 4 bytes are needed.
- leal 0x40(%esi), %esp
+ leal (0x1e4+4)(%esi), %esp
1: popl %ebp
subl $1b, %ebp