[XTENSA] Fix clobbered register in asm macro
We dangerously re-used an input operand to an asm macro
without defining a constraint. By defining a separate
output operand (instead of input/output operand), the
compiler is more flexible during register allocation.
Signed-off-by: Chris Zankel <chris@zankel.net>
diff --git a/include/asm-xtensa/uaccess.h b/include/asm-xtensa/uaccess.h
index d6352da0..b852842 100644
--- a/include/asm-xtensa/uaccess.h
+++ b/include/asm-xtensa/uaccess.h
@@ -26,6 +26,7 @@
#include <asm/current.h>
#include <asm/asm-offsets.h>
#include <asm/processor.h>
+#include <asm/types.h>
/*
* These assembly macros mirror the C macros that follow below. They
@@ -118,7 +119,7 @@
* <at> destroyed (actually, (TASK_SIZE + 1 - size))
*/
.macro user_ok aa, as, at, error
- movi \at, (TASK_SIZE+1)
+ movi \at, __XTENSA_UL_CONST(TASK_SIZE)
bgeu \as, \at, \error
sub \at, \at, \as
bgeu \aa, \at, \error
@@ -226,20 +227,21 @@
__pu_err; \
})
-#define __put_user_size(x,ptr,size,retval) \
-do { \
- retval = 0; \
- switch (size) { \
- case 1: __put_user_asm(x,ptr,retval,1,"s8i"); break; \
- case 2: __put_user_asm(x,ptr,retval,2,"s16i"); break; \
- case 4: __put_user_asm(x,ptr,retval,4,"s32i"); break; \
- case 8: { \
- __typeof__(*ptr) __v64 = x; \
- retval = __copy_to_user(ptr,&__v64,8); \
- break; \
- } \
- default: __put_user_bad(); \
- } \
+#define __put_user_size(x,ptr,size,retval) \
+do { \
+ int __cb; \
+ retval = 0; \
+ switch (size) { \
+ case 1: __put_user_asm(x,ptr,retval,1,"s8i",__cb); break; \
+ case 2: __put_user_asm(x,ptr,retval,2,"s16i",__cb); break; \
+ case 4: __put_user_asm(x,ptr,retval,4,"s32i",__cb); break; \
+ case 8: { \
+ __typeof__(*ptr) __v64 = x; \
+ retval = __copy_to_user(ptr,&__v64,8); \
+ break; \
+ } \
+ default: __put_user_bad(); \
+ } \
} while (0)
@@ -267,14 +269,14 @@
#define __check_align_1 ""
#define __check_align_2 \
- " _bbci.l %2, 0, 1f \n" \
- " movi %0, %3 \n" \
+ " _bbci.l %3, 0, 1f \n" \
+ " movi %0, %4 \n" \
" _j 2f \n"
#define __check_align_4 \
- " _bbsi.l %2, 0, 0f \n" \
- " _bbci.l %2, 1, 1f \n" \
- "0: movi %0, %3 \n" \
+ " _bbsi.l %3, 0, 0f \n" \
+ " _bbci.l %3, 1, 1f \n" \
+ "0: movi %0, %4 \n" \
" _j 2f \n"
@@ -286,24 +288,24 @@
* WARNING: If you modify this macro at all, verify that the
* __check_align_* macros still work.
*/
-#define __put_user_asm(x, addr, err, align, insn) \
- __asm__ __volatile__( \
- __check_align_##align \
- "1: "insn" %1, %2, 0 \n" \
- "2: \n" \
- " .section .fixup,\"ax\" \n" \
- " .align 4 \n" \
- "4: \n" \
- " .long 2b \n" \
- "5: \n" \
- " l32r %2, 4b \n" \
- " movi %0, %3 \n" \
- " jx %2 \n" \
- " .previous \n" \
- " .section __ex_table,\"a\" \n" \
- " .long 1b, 5b \n" \
- " .previous" \
- :"=r" (err) \
+#define __put_user_asm(x, addr, err, align, insn, cb) \
+ __asm__ __volatile__( \
+ __check_align_##align \
+ "1: "insn" %2, %3, 0 \n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ " .align 4 \n" \
+ "4: \n" \
+ " .long 2b \n" \
+ "5: \n" \
+ " l32r %1, 4b \n" \
+ " movi %0, %4 \n" \
+ " jx %1 \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " .long 1b, 5b \n" \
+ " .previous" \
+ :"=r" (err), "=r" (cb) \
:"r" ((int)(x)), "r" (addr), "i" (-EFAULT), "0" (err))
#define __get_user_nocheck(x,ptr,size) \
@@ -328,11 +330,12 @@
#define __get_user_size(x,ptr,size,retval) \
do { \
+ int __cb; \
retval = 0; \
switch (size) { \
- case 1: __get_user_asm(x,ptr,retval,1,"l8ui"); break; \
- case 2: __get_user_asm(x,ptr,retval,2,"l16ui"); break; \
- case 4: __get_user_asm(x,ptr,retval,4,"l32i"); break; \
+ case 1: __get_user_asm(x,ptr,retval,1,"l8ui",__cb); break; \
+ case 2: __get_user_asm(x,ptr,retval,2,"l16ui",__cb); break; \
+ case 4: __get_user_asm(x,ptr,retval,4,"l32i",__cb); break; \
case 8: retval = __copy_from_user(&x,ptr,8); break; \
default: (x) = __get_user_bad(); \
} \
@@ -343,25 +346,25 @@
* WARNING: If you modify this macro at all, verify that the
* __check_align_* macros still work.
*/
-#define __get_user_asm(x, addr, err, align, insn) \
+#define __get_user_asm(x, addr, err, align, insn, cb) \
__asm__ __volatile__( \
__check_align_##align \
- "1: "insn" %1, %2, 0 \n" \
+ "1: "insn" %2, %3, 0 \n" \
"2: \n" \
" .section .fixup,\"ax\" \n" \
" .align 4 \n" \
"4: \n" \
" .long 2b \n" \
"5: \n" \
- " l32r %2, 4b \n" \
- " movi %1, 0 \n" \
- " movi %0, %3 \n" \
- " jx %2 \n" \
+ " l32r %1, 4b \n" \
+ " movi %2, 0 \n" \
+ " movi %0, %4 \n" \
+ " jx %1 \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" .long 1b, 5b \n" \
" .previous" \
- :"=r" (err), "=r" (x) \
+ :"=r" (err), "=r" (cb), "=r" (x) \
:"r" (addr), "i" (-EFAULT), "0" (err))