[PATCH 2.6.17-rc6 5/9] Add kmemleak support for i386

[Catalin Marinas <catalin.marinas@gmail.com>]

From: Catalin Marinas <catalin.marinas@arm.com>

This patch modifies the vmlinux.lds.S script and adds the backtrace support
for i386 to be used with kmemleak.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---

 arch/i386/kernel/vmlinux.lds.S |    4 ++++
 include/asm-i386/processor.h   |   12 ++++++++++++
 include/asm-i386/thread_info.h |   10 +++++++++-
 3 files changed, 25 insertions(+), 1 deletions(-)

diff --git a/arch/i386/kernel/vmlinux.lds.S b/arch/i386/kernel/vmlinux.lds.S
index 8831303..370480e 100644
--- a/arch/i386/kernel/vmlinux.lds.S
+++ b/arch/i386/kernel/vmlinux.lds.S
@@ -38,6 +38,7 @@ SECTIONS
   RODATA
 
   /* writeable */
+  _sdata = .;			/* Start of data section */
   .data : AT(ADDR(.data) - LOAD_OFFSET) {	/* Data */
 	*(.data)
 	CONSTRUCTORS
@@ -140,6 +141,9 @@ SECTIONS
   __per_cpu_start = .;
   .data.percpu  : AT(ADDR(.data.percpu) - LOAD_OFFSET) { *(.data.percpu) }
   __per_cpu_end = .;
+  __memleak_offsets_start = .;
+  .init.memleak_offsets : AT(ADDR(.init.memleak_offsets) - LOAD_OFFSET) { *(.init.memleak_offsets) }
+  __memleak_offsets_end = .;
   . = ALIGN(4096);
   __init_end = .;
   /* freed after init ends here */
diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h
index 805f0dc..9b6568a 100644
--- a/include/asm-i386/processor.h
+++ b/include/asm-i386/processor.h
@@ -743,4 +743,16 @@ #else
 #define mcheck_init(c) do {} while(0)
 #endif
 
+#ifdef CONFIG_FRAME_POINTER
+static inline unsigned long arch_call_address(void *frame)
+{
+	return *(unsigned long *) (frame + 4);
+}
+
+static inline void *arch_prev_frame(void *frame)
+{
+	return *(void **) frame;
+}
+#endif
+
 #endif /* __ASM_I386_PROCESSOR_H */
diff --git a/include/asm-i386/thread_info.h b/include/asm-i386/thread_info.h
index 1f7d48c..7e7c508 100644
--- a/include/asm-i386/thread_info.h
+++ b/include/asm-i386/thread_info.h
@@ -102,12 +102,20 @@ #define alloc_thread_info(tsk)					\
 		struct thread_info *ret;			\
 								\
 		ret = kmalloc(THREAD_SIZE, GFP_KERNEL);		\
+		memleak_ignore(ret);				\
 		if (ret)					\
 			memset(ret, 0, THREAD_SIZE);		\
 		ret;						\
 	})
 #else
-#define alloc_thread_info(tsk) kmalloc(THREAD_SIZE, GFP_KERNEL)
+#define alloc_thread_info(tsk)					\
+	({							\
+		struct thread_info *ret;			\
+								\
+		ret = kmalloc(THREAD_SIZE, GFP_KERNEL);		\
+		memleak_ignore(ret);				\
+		ret;						\
+	})
 #endif
 
 #define free_thread_info(info)	kfree(info)