[34-longterm 033/209] um: remove PAGE_SIZE alignment in linker script causing kernel segfault.

From: Paul Gortmaker
Date: Thu Apr 14 2011 - 14:31:07 EST

From: Richard Weinberger <richard@xxxxxx>

| This is a commit scheduled for the next v2.6.34 longterm release. |
| If you see a problem with using this for longterm, please comment.|

commit 6915e04f8847bea16d0890f559694ad8eedd026c upstream.

The linker script cleanup that I did in commit 5d150a97f93 ("um: Clean up
linker script using standard macros.") (2.6.32) accidentally introduced an
ALIGN(PAGE_SIZE) when converting to use INIT_TEXT_SECTION; Richard
Weinberger reported that this causes the kernel to segfault with

I'm not certain why this extra alignment is a problem, but it seems likely
it is because previously

__init_begin = _stext = _text = _sinittext

and with the extra ALIGN(PAGE_SIZE), _sinittext becomes different from the
rest. So there is likely a bug here where something is assuming that
_sinittext is the same as one of those other symbols. But reverting the
accidental change fixes the regression, so it seems worth committing that

Signed-off-by: Tim Abbott <tabbott@xxxxxxxxxxx>
Reported-by: Richard Weinberger <richard@xxxxxx>
Cc: Jeff Dike <jdike@xxxxxxxxxxx>
Tested by: Antoine Martin <antoine@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
arch/um/kernel/uml.lds.S | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/um/kernel/uml.lds.S b/arch/um/kernel/uml.lds.S
index e7a6cca..664f942 100644
--- a/arch/um/kernel/uml.lds.S
+++ b/arch/um/kernel/uml.lds.S
@@ -22,7 +22,7 @@ SECTIONS
_text = .;
_stext = .;
__init_begin = .;

.text :

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