[PATCH] mips: fix uninitialized warning when using get_user()

[Sam Ravnborg <sam@ravnborg.org>]

Fix following type of warnings:
arch/mips/kernel/../../../fs/binfmt_elf.c: In function 'vma_dump_size'
arch/mips/kernel/../../../fs/binfmt_elf.c:1139:
warning: word may be used uninitialized in this function

The warning was tracked down to the implementation of the get_user()
macro in uaccess.h.
Other architectures assign the supplied variable to 0 if
access check fails - do the same for mips.

This patch intentionally do the minimal fix as the configuration
I used (bigsur_defconfig) did not produce warnings from
the other get_user() variants.

This fixes bigsur_defconfig build that other
failed due to -Werror.

The warnings was triggered with gcc 4.1.2

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
Well - I complained so I took a closer look.
This seems to be the correct fix.

I have only build tested this patch.
As the box I sit on is rather slow I do not have
before/after number for vmlinux size - sorry!

        Sam

 arch/mips/include/asm/uaccess.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index c2d53c1..1cd4bb6 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -248,6 +248,8 @@ do {                                                        
                \
        might_fault();                                                  \
        if (likely(access_ok(VERIFY_READ,  __gu_ptr, size)))            \
                __get_user_common((x), size, __gu_ptr);                 \
+       else                                                            \
+               (x) = 0;                                                \
                                                                        \
        __gu_err;                                                       \
 })
-- 
1.6.0.6