Re: [PATCH v8 5/5] arm64: futex: support futex with FEAT_LSUI

[Yeoreum Yun <yeoreum.yun@arm.com>]

[...]
> static __always_inline int
> __lsui_cmpxchg32(u32 __user *uaddr, u32 oldval, u32 newval, u32 *oval)
> {
> 	uaddr64 = (u64 __user *)PTR_ALIGN_DOWN(uaddr, sizeof(u64));
> 	u64 oval64, nval64, orig64;
>
> 	if (get_user(oval64, uaddr64)
> 		return -EFAULT;
>
> 	if (IS_ALIGNED(addr, sizeof(u64)) == IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN))  {
> 		FIELD_MODIFY(GENMASK_U64(31, 0), &oval64, oldval);
> 		FIELD_MODIFY(GENMASK_U64(31, 0), &nval64, newval);
> 	} else {
> 		FIELD_MODIFY(GENMASK_U64(63, 32), &oval64, oldval);
> 		FIELD_MODIFY(GENMASK_U64(63, 32), &nval64, newval);
> 	}
> 	orig64 = oval64;
>
> 	if (__lsui_cmpxchg64(uaddr_al, &oval64, nval64))
> 		return -EFAULT;
>
> 	if (oval64 != orig64)
> 		return -EAGAIN;
>
> 	*oval = oldval;
> 	return 0;
> }

Oh, I misread the condition. Thanks for your suggetion.
Please ignore my previous email.

--
Sincerely,
Yeoreum Yun