fs/binfmt_flat.c: split the stack & data alignments

[pandora-kernel.git] / fs / binfmt_flat.c

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 49566c1..b865622 100644 (file)
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -56,15 +56,22 @@
 #endif
 
 /*
- * User data (stack, data section and bss) needs to be aligned
- * for the same reasons as SLAB memory is, and to the same amount.
- * Avoid duplicating architecture specific code by using the same
- * macro as with SLAB allocation:
+ * User data (data section and bss) needs to be aligned.
+ * We pick 0x20 here because it is the max value elf2flt has always
+ * used in producing FLAT files, and because it seems to be large
+ * enough to make all the gcc alignment related tests happy.
+ */
+#define FLAT_DATA_ALIGN        (0x20)
+
+/*
+ * User data (stack) also needs to be aligned.
+ * Here we can be a bit looser than the data sections since this
+ * needs to only meet arch ABI requirements.
  */
 #ifdef ARCH_SLAB_MINALIGN
-#define FLAT_DATA_ALIGN        (ARCH_SLAB_MINALIGN)
+#define FLAT_STACK_ALIGN       (ARCH_SLAB_MINALIGN)
 #else
-#define FLAT_DATA_ALIGN        (sizeof(void *))
+#define FLAT_STACK_ALIGN       (sizeof(void *))
 #endif
 
 #define RELOC_FAILED 0xff00ff01                /* Relocation incorrect somewhere */
@@ -129,7 +136,7 @@ static unsigned long create_flat_tables(
 
        sp = (unsigned long *)p;
        sp -= (envc + argc + 2) + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
-       sp = (unsigned long *) ((unsigned long)sp & -FLAT_DATA_ALIGN);
+       sp = (unsigned long *) ((unsigned long)sp & -FLAT_STACK_ALIGN);
        argv = sp + 1 + (flat_argvp_envp_on_stack() ? 2 : 0);
        envp = argv + (argc + 1);
 
@@ -876,7 +883,7 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
        stack_len = TOP_OF_ARGS - bprm->p;             /* the strings */
        stack_len += (bprm->argc + 1) * sizeof(char *); /* the argv array */
        stack_len += (bprm->envc + 1) * sizeof(char *); /* the envp array */
-       stack_len += FLAT_DATA_ALIGN - 1;  /* reserve for upcoming alignment */
+       stack_len += FLAT_STACK_ALIGN - 1;  /* reserve for upcoming alignment */
        
        res = load_flat_file(bprm, &libinfo, 0, &stack_len);
        if (IS_ERR_VALUE(res))