Re: [PATCH v2] powerpc/uaccess: Implement unsafe_put_user() using 'asm goto'

From: Christophe Leroy
Date: Thu Apr 16 2020 - 08:42:36 EST




Le 16/04/2020 Ã 00:37, Segher Boessenkool a ÃcritÂ:
Hi!

On Wed, Apr 15, 2020 at 09:25:59AM +0000, Christophe Leroy wrote:
+#define __put_user_goto(x, ptr, label) \
+ __put_user_nocheck_goto((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label)

This line gets too long, can you break it up somehow?

This line has 86 chars.

powerpc arch tolerates lines with up to 90 chars, see arch/powerpc/tools/checkpatch.sh


+#define __put_user_asm_goto(x, addr, label, op) \
+ asm volatile goto( \
+ "1: " op "%U1%X1 %0,%1 # put_user\n" \
+ EX_TABLE(1b, %l2) \
+ : \
+ : "r" (x), "m" (*addr) \
+ : \
+ : label)

Same "%Un" problem as in the other patch. You could use "m<>" here,
but maybe just dropping "%Un" is better.

Ok.

I kept it to be consistent with the other patch.


+#ifdef __powerpc64__
+#define __put_user_asm2_goto(x, ptr, label) \
+ __put_user_asm_goto(x, ptr, label, "std")
+#else /* __powerpc64__ */
+#define __put_user_asm2_goto(x, addr, label) \
+ asm volatile goto( \
+ "1: stw%U1%X1 %0, %1\n" \
+ "2: stw%U1%X1 %L0, %L1\n" \
+ EX_TABLE(1b, %l2) \
+ EX_TABLE(2b, %l2) \
+ : \
+ : "r" (x), "m" (*addr) \
+ : \
+ : label)
+#endif /* __powerpc64__ */

Here, you should drop it for sure.

Done.

Christophe