Re: [RFC PATCH 01/10] powerpc: unify definition of M_IF_NEEDED

From: Christophe Leroy <christophe.leroy@c-s.fr>
To: Jason Yan <yanaijie@huawei.com>,
	mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org,
	diana.craciun@nxp.com, benh@kernel.crashing.org,
	paulus@samba.org, npiggin@gmail.com, keescook@chromium.org,
	kernel-hardening@lists.openwall.com
Cc: linux-kernel@vger.kernel.org, wangkefeng.wang@huawei.com,
	yebin10@huawei.com, thunder.leizhen@huawei.com,
	jingxiangfeng@huawei.com, fanchengyang@huawei.com
Subject: Re: [RFC PATCH 01/10] powerpc: unify definition of M_IF_NEEDED
Date: Mon, 29 Jul 2019 12:59:00 +0200	[thread overview]
Message-ID: <e9f2a7fc-ea70-e018-24b2-76cde6705780@c-s.fr> (raw)
In-Reply-To: <20190717080621.40424-2-yanaijie@huawei.com>


Le 17/07/2019 à 10:06, Jason Yan a écrit :
> M_IF_NEEDED is defined too many times. Move it to a common place.
> 
> Signed-off-by: Jason Yan <yanaijie@huawei.com>
> Cc: Diana Craciun <diana.craciun@nxp.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Christophe Leroy <christophe.leroy@c-s.fr>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Nicholas Piggin <npiggin@gmail.com>
> Cc: Kees Cook <keescook@chromium.org>

Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>

> ---
>   arch/powerpc/include/asm/nohash/mmu-book3e.h  | 10 ++++++++++
>   arch/powerpc/kernel/exceptions-64e.S          | 10 ----------
>   arch/powerpc/kernel/fsl_booke_entry_mapping.S | 10 ----------
>   arch/powerpc/kernel/misc_64.S                 |  5 -----
>   4 files changed, 10 insertions(+), 25 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/nohash/mmu-book3e.h b/arch/powerpc/include/asm/nohash/mmu-book3e.h
> index 4c9777d256fb..0877362e48fa 100644
> --- a/arch/powerpc/include/asm/nohash/mmu-book3e.h
> +++ b/arch/powerpc/include/asm/nohash/mmu-book3e.h
> @@ -221,6 +221,16 @@
>   #define TLBILX_T_CLASS2			6
>   #define TLBILX_T_CLASS3			7
>   
> +/*
> + * The mapping only needs to be cache-coherent on SMP, except on
> + * Freescale e500mc derivatives where it's also needed for coherent DMA.
> + */
> +#if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC)
> +#define M_IF_NEEDED	MAS2_M
> +#else
> +#define M_IF_NEEDED	0
> +#endif
> +
>   #ifndef __ASSEMBLY__
>   #include <asm/bug.h>
>   
> diff --git a/arch/powerpc/kernel/exceptions-64e.S b/arch/powerpc/kernel/exceptions-64e.S
> index 1cfb3da4a84a..fd49ec07ce4a 100644
> --- a/arch/powerpc/kernel/exceptions-64e.S
> +++ b/arch/powerpc/kernel/exceptions-64e.S
> @@ -1342,16 +1342,6 @@ skpinv:	addi	r6,r6,1				/* Increment */
>   	sync
>   	isync
>   
> -/*
> - * The mapping only needs to be cache-coherent on SMP, except on
> - * Freescale e500mc derivatives where it's also needed for coherent DMA.
> - */
> -#if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC)
> -#define M_IF_NEEDED	MAS2_M
> -#else
> -#define M_IF_NEEDED	0
> -#endif
> -
>   /* 6. Setup KERNELBASE mapping in TLB[0]
>    *
>    * r3 = MAS0 w/TLBSEL & ESEL for the entry we started in
> diff --git a/arch/powerpc/kernel/fsl_booke_entry_mapping.S b/arch/powerpc/kernel/fsl_booke_entry_mapping.S
> index ea065282b303..de0980945510 100644
> --- a/arch/powerpc/kernel/fsl_booke_entry_mapping.S
> +++ b/arch/powerpc/kernel/fsl_booke_entry_mapping.S
> @@ -153,16 +153,6 @@ skpinv:	addi	r6,r6,1				/* Increment */
>   	tlbivax 0,r9
>   	TLBSYNC
>   
> -/*
> - * The mapping only needs to be cache-coherent on SMP, except on
> - * Freescale e500mc derivatives where it's also needed for coherent DMA.
> - */
> -#if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC)
> -#define M_IF_NEEDED	MAS2_M
> -#else
> -#define M_IF_NEEDED	0
> -#endif
> -
>   #if defined(ENTRY_MAPPING_BOOT_SETUP)
>   
>   /* 6. Setup KERNELBASE mapping in TLB1[0] */
> diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
> index b55a7b4cb543..26074f92d4bc 100644
> --- a/arch/powerpc/kernel/misc_64.S
> +++ b/arch/powerpc/kernel/misc_64.S
> @@ -432,11 +432,6 @@ kexec_create_tlb:
>   	rlwimi	r9,r10,16,4,15		/* Setup MAS0 = TLBSEL | ESEL(r9) */
>   
>   /* Set up a temp identity mapping v:0 to p:0 and return to it. */
> -#if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC)
> -#define M_IF_NEEDED	MAS2_M
> -#else
> -#define M_IF_NEEDED	0
> -#endif
>   	mtspr	SPRN_MAS0,r9
>   
>   	lis	r9,(MAS1_VALID|MAS1_IPROT)@h
>