From d715e433b7ad19c02fc4becf0d5e9a59f97925de Mon Sep 17 00:00:00 2001
From: Anton Blanchard <anton@samba.org>
Date: Mon, 14 Nov 2011 12:54:47 +0000
Subject: [PATCH] powerpc: Copy down exception vectors after feature fixups
kdump fails because we try to execute an HV only instruction. Feature
fixups are being applied after we copy the exception vectors down to 0
so they miss out on any updates.
We have always had this issue but it only became critical in v3.0
when we added CFAR support (breaks POWER5) and v3.1 when we added
POWERNV (breaks everyone).
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org> [v3.0+]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
arch/powerpc/include/asm/sections.h | 2 +-
arch/powerpc/include/asm/synch.h | 1 +
arch/powerpc/kernel/kvm.c | 1 -
arch/powerpc/kernel/setup_32.c | 2 ++
arch/powerpc/kernel/setup_64.c | 1 +
arch/powerpc/lib/feature-fixups.c | 23 +++++++++++++++++++++++
6 files changed, 28 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h
index 6fbce725c710f..a0f358d4a00cd 100644
--- a/arch/powerpc/include/asm/sections.h
+++ b/arch/powerpc/include/asm/sections.h
@@ -8,7 +8,7 @@
#ifdef __powerpc64__
-extern char _end[];
+extern char __end_interrupts[];
static inline int in_kernel_text(unsigned long addr)
{
diff --git a/arch/powerpc/include/asm/synch.h b/arch/powerpc/include/asm/synch.h
index d7cab44643c51..87878c68d1c20 100644
--- a/arch/powerpc/include/asm/synch.h
+++ b/arch/powerpc/include/asm/synch.h
@@ -13,6 +13,7 @@
extern unsigned int __start___lwsync_fixup, __stop___lwsync_fixup;
extern void do_lwsync_fixups(unsigned long value, void *fixup_start,
void *fixup_end);
+extern void do_final_fixups(void);
static inline void eieio(void)
{
diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c
index 35f27646c4ff5..2985338d0e101 100644
--- a/arch/powerpc/kernel/kvm.c
+++ b/arch/powerpc/kernel/kvm.c
@@ -132,7 +132,6 @@ static void kvm_patch_ins_b(u32 *inst, int addr)
/* On relocatable kernels interrupts handlers and our code
can be in different regions, so we don't patch them */
- extern u32 __end_interrupts;
if ((ulong)inst < (ulong)&__end_interrupts)
return;
#endif
diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index c1ce86357ecb4..ac76108151135 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -107,6 +107,8 @@ notrace unsigned long __init early_init(unsigned long dt_ptr)
PTRRELOC(&__start___lwsync_fixup),
PTRRELOC(&__stop___lwsync_fixup));
+ do_final_fixups();
+
return KERNELBASE + offset;
}
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 1a9dea80a69b4..fb9bb46e7e881 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -359,6 +359,7 @@ void __init setup_system(void)
&__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
do_lwsync_fixups(cur_cpu_spec->cpu_features,
&__start___lwsync_fixup, &__stop___lwsync_fixup);
+ do_final_fixups();
/*
* Unflatten the device-tree passed by prom_init or kexec
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 0d08d0171392a..7a8a7487cee8d 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -18,6 +18,8 @@
#include <linux/init.h>
#include <asm/cputable.h>
#include <asm/code-patching.h>
+#include <asm/page.h>
+#include <asm/sections.h>
struct fixup_entry {
@@ -128,6 +130,27 @@ void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
}
}
+void do_final_fixups(void)
+{
+#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
+ int *src, *dest;
+ unsigned long length;
+
+ if (PHYSICAL_START == 0)
+ return;
+
+ src = (int *)(KERNELBASE + PHYSICAL_START);
+ dest = (int *)KERNELBASE;
+ length = (__end_interrupts - _stext) / sizeof(int);
+
+ while (length--) {
+ patch_instruction(dest, *src);
+ src++;
+ dest++;
+ }
+#endif
+}
+
#ifdef CONFIG_FTR_FIXUP_SELFTEST
#define check(x) \
--
2.30.2