[PATCH] ARM: Fix relocation if image end past uncompressed kernel end
From: Shawn Guo <hidden>
Date: 2011-04-22 05:19:14
Also in:
linux-omap
On Thu, Apr 21, 2011 at 11:23:22PM -0400, Nicolas Pitre wrote:
quoted hunk ↗ jump to hunk
On Thu, 21 Apr 2011, Nicolas Pitre wrote:quoted
On Thu, 21 Apr 2011, Nicolas Pitre wrote:quoted
On Thu, 21 Apr 2011, Tony Lindgren wrote:quoted
Otherwise we end up overwriting ourselves. This fixes booting on n900 after commit 6d7d0ae51574943bf571d269da3243257a2d15db (ARM: 6750/1: improvements to compressed/head.S). Signed-off-by: Tony Lindgren <tony@atomide.com>I don't understand why this is needed. The copy loop is explicitly copying from the end going backward exactly to cope with this possibility.I think your patch is 1) unneeded (see the copy loop code and the comment before it), and 2) simply hiding the real bug. I just need to modify the code in compressed/misc.c slightly for the lzma decompressor to start or stop working randomly. It seems that this code might be sensitive to slight displacement in memory caused by modifications to totally unrelated code. I'm still trying to track this down.I found the bugger. The problem was a bad stack alignment. ----- >8 From: Nicolas Pitre <redacted> ARM: zImage: make sure the stack is 64-bit aligned With ARMv5+ and EABI, the compiler expects a 64-bit aligned stack so instructions like STRD and LDRD can be used. Without this, mysterious boot failures were seen semi randomly with the LZMA decompressor. While at it, let's align .bss as well. Signed-off-by: Nicolas Pitre <redacted>diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 58ac434..79b5c62 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile@@ -74,7 +74,7 @@ ZTEXTADDR := $(CONFIG_ZBOOT_ROM_TEXT) ZBSSADDR := $(CONFIG_ZBOOT_ROM_BSS) else ZTEXTADDR := 0 -ZBSSADDR := ALIGN(4) +ZBSSADDR := ALIGN(8) endif SEDFLAGS = s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/diff --git a/arch/arm/boot/compressed/vmlinux.lds.in b/arch/arm/boot/compressed/vmlinux.lds.in index 5309909..ea80abe 100644 --- a/arch/arm/boot/compressed/vmlinux.lds.in +++ b/arch/arm/boot/compressed/vmlinux.lds.in@@ -54,6 +54,7 @@ SECTIONS .bss : { *(.bss) } _end = .; + . = ALIGN(8); /* the stack must be 64-bit aligned */ .stack : { *(.stack) } .stab 0 : { *(.stab) }
So this is the [PATCH 1/3] in the same set with following two? [PATCH 2/3] ARM: zImage: don't ignore error returned from decompress() [PATCH 3/3] ARM: zImage: the page table memory must be considered before relocation -- Regards, Shawn