parisc: uaccess: fix compiler warnings caused by __put_user casting
PATCH v2 1/1 parisc: uaccess: fix compiler warnings caused by __put_user casting
When targetting 32-bit processors, __put_user emits a pair of stw instructions for the 8-byte case. If the type of __val is a pointer, the marshalling code casts it to the wider integer type of u64, resulting in the following compiler warnings:
kernel/signal.c: In function 'copy_siginfo_to_user':
kernel/signal.c:2752:11: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] kernel/signal.c:2752:11: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast] [...]
This patch fixes the warnings by removing the marshalling code and using the correct output modifiers in the __put_{user,kernel}_asm64 macros so that GCC will allocate the right registers without the need to extract the two words explicitly.
---
v1->v2: Put the output modifier on the correct word, so 64-bit put_user
doesn't end up word-swapped.
arch/parisc/include/asm/uaccess.h | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-)
arch/parisc/include/asm/uaccess.h +4 -10
@@ -181,30 +181,24 @@ struct exception_data {#if !defined(CONFIG_64BIT )#define __put_kernel_asm64 (__val,ptr) do { \ - u64 __val64 = (u64)(__val); \ - u32 hi = (__val64) >> 32; \ - u32 lo = (__val64) & 0xffffffff; \ __asm__ __volatile__ ( \ "\n1:\tstw %2,0(%1)" \ - "\n2:\tstw %3,4(%1)\n\t" \ + "\n2:\tstw %R2,4(%1)\n\t" \ ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\ ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\ : "=r"(__pu_err) \ - : "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \ + : "r"(ptr), "r"(__val), "0"(__pu_err) \ : "r1"); \ } while (0)#define __put_user_asm64 (__val,ptr) do { \ - u64 __val64 = (u64)(__val); \ - u32 hi = (__val64) >> 32; \ - u32 lo = (__val64) & 0xffffffff; \ __asm__ __volatile__ ( \ "\n1:\tstw %2,0(%%sr3,%1)" \ - "\n2:\tstw %3,4(%%sr3,%1)\n\t" \ + "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \ ASM_EXCEPTIONTABLE_ENTRY(1b,fixup_put_user_skip_2)\ ASM_EXCEPTIONTABLE_ENTRY(2b,fixup_put_user_skip_1)\ : "=r"(__pu_err) \ - : "r"(ptr), "r"(hi), "r"(lo), "0"(__pu_err) \ + : "r"(ptr), "r"(__val), "0"(__pu_err) \ : "r1"); \ } while (0)
Signature · 1 line
1.8.0