From mboxrd@z Thu Jan  1 00:00:00 1970
From: catalin.marinas@arm.com (Catalin Marinas)
Date: Fri, 4 Dec 2015 13:27:43 +0000
Subject: [PATCH v8 1/4] arm64: Store struct task_info in sp_el0
In-Reply-To: <1449226948-14251-2-git-send-email-james.morse@arm.com>
References: <1449226948-14251-1-git-send-email-james.morse@arm.com>
 <1449226948-14251-2-git-send-email-james.morse@arm.com>
Message-ID: <20151204132743.GH10123@e104818-lin.cambridge.arm.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Fri, Dec 04, 2015 at 11:02:25AM +0000, James Morse wrote:
> --- a/arch/arm64/kernel/entry.S
> +++ b/arch/arm64/kernel/entry.S
[...]
> @@ -599,6 +606,8 @@ ENTRY(cpu_switch_to)
>  	ldp	x29, x9, [x8], #16
>  	ldr	lr, [x8]
>  	mov	sp, x9
> +	and	x9, x9, #~(THREAD_SIZE - 1)
> +	msr	sp_el0, x9
>  	ret
>  ENDPROC(cpu_switch_to)

At the beginning of the cpu_switch_to function, could we do
"mrs x9, sp_el0" instead to avoid the "and ... ~(THREAD_SIZE-1)"?

Otherwise:

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>