From 86b1e8dd83cbb0fcbf3d61d2b461df8be1f528cf Mon Sep 17 00:00:00 2001
From: Shaohua Li <shaohua.li@intel.com>
Date: Tue, 18 Jan 2011 08:57:49 +0800
Subject: x86: Make relocatable kernel work with new binutils

The CONFIG_RELOCATABLE=y option is broken with new binutils, which will make
boot panic.

According to Lu Hongjiu, the affected binutils are from 2.20.51.0.12 to
2.21.51.0.3, which are release since Oct 22 this year. At least ubuntu 10.10 is
using such binutils. See:

    http://sourceware.org/bugzilla/show_bug.cgi?id=12327

The reason of the boot panic is that we have 'jiffies = jiffies_64;' in
vmlinux.lds.S. The jiffies isn't in any section. In kernel build, there is
warning saying jiffies is an absolute address and can't be relocatable. At
runtime, jiffies will have virtual address 0.

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Cc: Lu Hongjiu<hongjiu.lu@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
LKML-Reference: <1295312269.1949.725.camel@sli10-conroe>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index bf47007..b34ab80 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -34,11 +34,9 @@ OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT)
 #ifdef CONFIG_X86_32
 OUTPUT_ARCH(i386)
 ENTRY(phys_startup_32)
-jiffies = jiffies_64;
 #else
 OUTPUT_ARCH(i386:x86-64)
 ENTRY(phys_startup_64)
-jiffies_64 = jiffies;
 #endif
 
 #if defined(CONFIG_X86_64) && defined(CONFIG_DEBUG_RODATA)
@@ -142,6 +140,15 @@ SECTIONS
 		CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES)
 
 		DATA_DATA
+		/*
+		 * Workaround a binutils (2.20.51.0.12 to 2.21.51.0.3) bug.
+		 * This makes jiffies relocatable in such binutils
+		 */
+#ifdef CONFIG_X86_32
+		jiffies = jiffies_64;
+#else
+		jiffies_64 = jiffies;
+#endif
 		CONSTRUCTORS
 
 		/* rarely changed data like cpu maps */
-- 
cgit v0.10.2


From 7b698ea377e10b074ceef0d79218e6622d618421 Mon Sep 17 00:00:00 2001
From: Brian Gerst <brgerst@gmail.com>
Date: Mon, 17 Jan 2011 07:32:10 -0500
Subject: x86: Clear irqstack thread_info

Mathias Merz reported that v2.6.37 failed to boot on his
system.

Make sure that the thread_info part of the irqstack is
initialized to zeroes.

Reported-and-Tested-by: Matthias Merz <linux@merz-ka.de>
Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <AANLkTimyKXfJ1x8tgwrr1hYnNLrPfgE1NTe4z7L6tUDm@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 96656f2..5206bb9 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -129,8 +129,7 @@ void __cpuinit irq_ctx_init(int cpu)
 	irqctx = page_address(alloc_pages_node(cpu_to_node(cpu),
 					       THREAD_FLAGS,
 					       THREAD_ORDER));
-	irqctx->tinfo.task		= NULL;
-	irqctx->tinfo.exec_domain	= NULL;
+	memset(&irqctx->tinfo, 0, sizeof(struct thread_info));
 	irqctx->tinfo.cpu		= cpu;
 	irqctx->tinfo.preempt_count	= HARDIRQ_OFFSET;
 	irqctx->tinfo.addr_limit	= MAKE_MM_SEG(0);
@@ -140,10 +139,8 @@ void __cpuinit irq_ctx_init(int cpu)
 	irqctx = page_address(alloc_pages_node(cpu_to_node(cpu),
 					       THREAD_FLAGS,
 					       THREAD_ORDER));
-	irqctx->tinfo.task		= NULL;
-	irqctx->tinfo.exec_domain	= NULL;
+	memset(&irqctx->tinfo, 0, sizeof(struct thread_info));
 	irqctx->tinfo.cpu		= cpu;
-	irqctx->tinfo.preempt_count	= 0;
 	irqctx->tinfo.addr_limit	= MAKE_MM_SEG(0);
 
 	per_cpu(softirq_ctx, cpu) = irqctx;
-- 
cgit v0.10.2