[PATCH RESEND] arch/microblaze: add support for get_user() of size 8 bytes

[Randy Dunlap]

From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>

arch/microblaze/ is missing support for get_user() of size 8 bytes,
so add it by using __copy_from_user().

Fixes these build errors:
   drivers/infiniband/core/uverbs_main.o: In function `ib_uverbs_write':
   drivers/infiniband/core/.tmp_gl_uverbs_main.o:(.text+0x13a4): undefined reference to `__user_bad'
   drivers/android/binder.o: In function `binder_thread_write':
   drivers/android/.tmp_gl_binder.o:(.text+0xda6c): undefined reference to `__user_bad'
   drivers/android/.tmp_gl_binder.o:(.text+0xda98): undefined reference to `__user_bad'
   drivers/android/.tmp_gl_binder.o:(.text+0xdf10): undefined reference to `__user_bad'
   drivers/android/.tmp_gl_binder.o:(.text+0xe498): undefined reference to `__user_bad'
   drivers/android/binder.o:drivers/android/.tmp_gl_binder.o:(.text+0xea78): more undefined references to `__user_bad' follow

'make allmodconfig' now builds successfully for arch/microblaze/.

Fixes: 538722ca3b76 ("microblaze: fix get_user/put_user side-effects")
Reported-by: kbuild test robot <lkp@xxxxxxxxx>
Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Steven J. Magnani <steve@xxxxxxxxxxxxxxx>
Cc: Michal Simek <monstr@xxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Cc: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Doug Ledford <dledford@xxxxxxxxxx>
Reviewed-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
What is a reasonable path for having this patch merged?
Leon Romanovsky <leonro@xxxxxxxxxxxx> has tested it.
I have sent several emails to Micahl Simek but he seems to have
dropped active maintenance of arch/microblaze/.

 arch/microblaze/include/asm/uaccess.h |    6 ++++++
 1 file changed, 6 insertions(+)

--- lnx-53-rc3.orig/arch/microblaze/include/asm/uaccess.h
+++ lnx-53-rc3/arch/microblaze/include/asm/uaccess.h
@@ -186,6 +186,9 @@ extern long __user_bad(void);
 			__get_user_asm("lw", __gu_addr, __gu_val,	\
 				       __gu_err);			\
 			break;						\
+		case 8:							\
+			__gu_err = __copy_from_user(&__gu_val, __gu_addr, 8);\
+			break;						\
 		default:						\
 			__gu_err = __user_bad();			\
 			break;						\
@@ -212,6 +215,9 @@ extern long __user_bad(void);
 	case 4:								\
 		__get_user_asm("lw", (ptr), __gu_val, __gu_err);	\
 		break;							\
+	case 8:								\
+		__gu_err = __copy_from_user(&__gu_val, ptr, 8);		\
+		break;							\
 	default:							\
 		/* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
 	}								\