This is a note to let you know that I've just added the patch titled

    avr32: fix out-of-range jump in large kernels

to the 3.12-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     avr32-fix-out-of-range-jump-in-large-kernels.patch
and it can be found in the queue-3.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From d617b338bbfdd77e9cbd8e7dc949cee3dd73d575 Mon Sep 17 00:00:00 2001
From: Andreas Bießmann <[email protected]>
Date: Thu, 24 Oct 2013 12:31:04 +0200
Subject: avr32: fix out-of-range jump in large kernels

From: Andreas Bießmann <[email protected]>

commit d617b338bbfdd77e9cbd8e7dc949cee3dd73d575 upstream.

This patch fixes following error (for big kernels):

---8<---
arch/avr32/boot/u-boot/head.o: In function `no_tag_table':
(.init.text+0x44): relocation truncated to fit: R_AVR32_22H_PCREL against 
symbol `panic' defined in .text.unlikely section in kernel/built-in.o
arch/avr32/kernel/built-in.o: In function `bad_return':
(.ex.text+0x236): relocation truncated to fit: R_AVR32_22H_PCREL against symbol 
`panic' defined in .text.unlikely section in kernel/built-in.o
--->8---

It comes up when the kernel increases and 'panic()' is too far away to fit in
the +/- 2MiB range. Which in turn issues from the 21-bit displacement in
'br{cond4}' mnemonic which is one of the two ways to do jumps (rjmp has just
10-bit displacement and therefore a way smaller range). This fact was stated
before in 8d29b7b9f81d6b83d869ff054e6c189d6da73f1f.
One solution to solve this is to add a local storage for the symbol address
and just load the $pc with that value.

Signed-off-by: Andreas Bießmann <[email protected]>
Acked-by: Hans-Christian Egtvedt <[email protected]>
Cc: Haavard Skinnemoen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/avr32/boot/u-boot/head.S    |    5 ++++-
 arch/avr32/kernel/entry-avr32b.S |    3 ++-
 2 files changed, 6 insertions(+), 2 deletions(-)

--- a/arch/avr32/boot/u-boot/head.S
+++ b/arch/avr32/boot/u-boot/head.S
@@ -73,8 +73,11 @@ init_sr:
        .long   0x007f0000      /* Supervisor mode, everything masked */
 stack_addr:
        .long   init_thread_union
+panic_addr:
+       .long   panic
 
 no_tag_table:
        sub     r12, pc, (. - 2f)
-       bral    panic
+       /* branch to panic() which can be far away with that construct */
+       lddpc   pc, panic_addr
 2:     .asciz  "Boot loader didn't provide correct magic number\n"
--- a/arch/avr32/kernel/entry-avr32b.S
+++ b/arch/avr32/kernel/entry-avr32b.S
@@ -401,9 +401,10 @@ handle_critical:
        /* We should never get here... */
 bad_return:
        sub     r12, pc, (. - 1f)
-       bral    panic
+       lddpc   pc, 2f
        .align  2
 1:     .asciz  "Return from critical exception!"
+2:     .long   panic
 
        .align  1
 do_bus_error_write:


Patches currently in stable-queue which might be from [email protected] are

queue-3.12/avr32-fix-out-of-range-jump-in-large-kernels.patch
queue-3.12/avr32-setup-crt-for-early-panic.patch
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