Stafford Horne a6db3aab9c openrisc: Fix issue with get_user for 64-bit values ... commit d877322bc1 upstream. A build failure was raised by kbuild with the following error. drivers/android/binder.c: Assembler messages: drivers/android/binder.c:3861: Error: unrecognized keyword/register name `l.lwz ?ap,4(r24)' drivers/android/binder.c:3866: Error: unrecognized keyword/register name `l.addi ?ap,r0,0' The issue is with 64-bit get_user() calls on openrisc. I traced this to a problem where in the internally in the get_user macros there is a cast to long __gu_val this causes GCC to think the get_user call is 32-bit. This binder code is really long and GCC allocates register r30, which triggers the issue. The 64-bit get_user asm tries to get the 64-bit pair register, which for r30 overflows the general register names and returns the dummy register ?ap. The fix here is to move the temporary variables into the asm macros. We use a 32-bit __gu_tmp for 32-bit and smaller macro and a 64-bit tmp in the 64-bit macro. The cast in the 64-bit macro has a trick of casting through __typeof__((x)-(x)) which avoids the below warning. This was barrowed from riscv. arch/openrisc/include/asm/uaccess.h:240:8: warning: cast to pointer from integer of different size I tested this in a small unit test to check reading between 64-bit and 32-bit pointers to 64-bit and 32-bit values in all combinations. Also I ran make C=1 to confirm no new sparse warnings came up. It all looks clean to me. Link: https://lore.kernel.org/lkml/202008200453.ohnhqkjQ%25lkp@intel.com/ Signed-off-by: Stafford Horne <shorne@gmail.com> Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-11-01 12:01:06 +01:00
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boot/dts	or1k: dts: Add ethoc device to SMP devicetree	2019-08-31 11:56:19 +09:00
configs	configs: get rid of obsolete CONFIG_ENABLE_WARN_DEPRECATED	2019-03-07 18:32:02 -08:00
include	openrisc: Fix issue with get_user for 64-bit values	2020-11-01 12:01:06 +01:00
kernel	openrisc: Fix oops caused when dumping stack	2020-08-21 13:05:35 +02:00
lib	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
mm	openrisc: Fix cache API compile issue when not inlining	2020-09-23 12:40:36 +02:00
Kconfig	docs: kbuild: convert docs to ReST and rename to *.rst	2019-06-14 14:21:21 -06:00
Kconfig.debug	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	openrisc: remove unneeded code in arch/openrisc/Makefile	2019-01-17 23:42:59 +09:00