Merge branch 'master' into csb1725

[mv-sheeva.git] / arch / x86 / oprofile / backtrace.c

diff --git a/arch/x86/oprofile/backtrace.c b/arch/x86/oprofile/backtrace.c
index 3855096c59b81910fe827c76151e84bbac836770..2d49d4e19a3619c0be2c7d17a892b8aea582048f 100644 (file)
--- a/arch/x86/oprofile/backtrace.c
+++ b/arch/x86/oprofile/backtrace.c
@@ -14,6 +14,7 @@
 #include <asm/ptrace.h>
 #include <asm/uaccess.h>
 #include <asm/stacktrace.h>
+#include <linux/compat.h>
 
 static void backtrace_warning_symbol(void *data, char *msg,
                                     unsigned long symbol)
@@ -48,14 +49,12 @@ static struct stacktrace_ops backtrace_ops = {
        .walk_stack     = print_context_stack,
 };
 
-struct frame_head {
-       struct frame_head *bp;
-       unsigned long ret;
-} __attribute__((packed));
-
-static struct frame_head *dump_user_backtrace(struct frame_head *head)
+#ifdef CONFIG_COMPAT
+static struct stack_frame_ia32 *
+dump_user_backtrace_32(struct stack_frame_ia32 *head)
 {
-       struct frame_head bufhead[2];
+       struct stack_frame_ia32 bufhead[2];
+       struct stack_frame_ia32 *fp;
 
        /* Also check accessibility of one struct frame_head beyond */
        if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
@@ -63,20 +62,66 @@ static struct frame_head *dump_user_backtrace(struct frame_head *head)
        if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
                return NULL;
 
-       oprofile_add_trace(bufhead[0].ret);
+       fp = (struct stack_frame_ia32 *) compat_ptr(bufhead[0].next_frame);
+
+       oprofile_add_trace(bufhead[0].return_address);
+
+       /* frame pointers should strictly progress back up the stack
+       * (towards higher addresses) */
+       if (head >= fp)
+               return NULL;
+
+       return fp;
+}
+
+static inline int
+x86_backtrace_32(struct pt_regs * const regs, unsigned int depth)
+{
+       struct stack_frame_ia32 *head;
+
+       /* User process is 32-bit */
+       if (!current || !test_thread_flag(TIF_IA32))
+               return 0;
+
+       head = (struct stack_frame_ia32 *) regs->bp;
+       while (depth-- && head)
+               head = dump_user_backtrace_32(head);
+
+       return 1;
+}
+
+#else
+static inline int
+x86_backtrace_32(struct pt_regs * const regs, unsigned int depth)
+{
+       return 0;
+}
+#endif /* CONFIG_COMPAT */
+
+static struct stack_frame *dump_user_backtrace(struct stack_frame *head)
+{
+       struct stack_frame bufhead[2];
+
+       /* Also check accessibility of one struct stack_frame beyond */
+       if (!access_ok(VERIFY_READ, head, sizeof(bufhead)))
+               return NULL;
+       if (__copy_from_user_inatomic(bufhead, head, sizeof(bufhead)))
+               return NULL;
+
+       oprofile_add_trace(bufhead[0].return_address);
 
        /* frame pointers should strictly progress back up the stack
         * (towards higher addresses) */
-       if (head >= bufhead[0].bp)
+       if (head >= bufhead[0].next_frame)
                return NULL;
 
-       return bufhead[0].bp;
+       return bufhead[0].next_frame;
 }
 
 void
 x86_backtrace(struct pt_regs * const regs, unsigned int depth)
 {
-       struct frame_head *head = (struct frame_head *)frame_pointer(regs);
+       struct stack_frame *head = (struct stack_frame *)frame_pointer(regs);
 
        if (!user_mode_vm(regs)) {
                unsigned long stack = kernel_stack_pointer(regs);
@@ -86,6 +131,9 @@ x86_backtrace(struct pt_regs * const regs, unsigned int depth)
                return;
        }
 
+       if (x86_backtrace_32(regs, depth))
+               return;
+
        while (depth-- && head)
                head = dump_user_backtrace(head);
 }