From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot1-f70.google.com (mail-ot1-f70.google.com [209.85.210.70]) by kanga.kvack.org (Postfix) with ESMTP id 30BEA6B497D for ; Tue, 27 Nov 2018 12:09:38 -0500 (EST) Received: by mail-ot1-f70.google.com with SMTP id t13so8466452otk.4 for ; Tue, 27 Nov 2018 09:09:38 -0800 (PST) Received: from foss.arm.com (usa-sjc-mx-foss1.foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id e26si1900562oth.259.2018.11.27.09.09.36 for ; Tue, 27 Nov 2018 09:09:36 -0800 (PST) Date: Tue, 27 Nov 2018 17:09:32 +0000 From: Catalin Marinas Subject: Re: [PATCH V3 2/5] arm64: mm: Introduce DEFAULT_MAP_WINDOW Message-ID: <20181127170931.GC3563@arrakis.emea.arm.com> References: <20181114133920.7134-1-steve.capper@arm.com> <20181114133920.7134-3-steve.capper@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181114133920.7134-3-steve.capper@arm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Steve Capper Cc: linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, will.deacon@arm.com, jcm@redhat.com, ard.biesheuvel@linaro.org Hi Steve, On Wed, Nov 14, 2018 at 01:39:17PM +0000, Steve Capper wrote: > diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h > index 3e2091708b8e..da41a2655b69 100644 > --- a/arch/arm64/include/asm/processor.h > +++ b/arch/arm64/include/asm/processor.h > @@ -25,6 +25,9 @@ > #define USER_DS (TASK_SIZE_64 - 1) > > #ifndef __ASSEMBLY__ > + > +#define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS) > + > #ifdef __KERNEL__ That's a strange place to place DEFAULT_MAP_WINDOW_64. Did you have any #include dependency issues? If yes, we could look at cleaning them up, maybe moving these definitions into a separate file. (also, if you do a clean-up I don't think we need __KERNEL__ anymore) > > #include > @@ -51,13 +54,16 @@ > TASK_SIZE_32 : TASK_SIZE_64) > #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \ > TASK_SIZE_32 : TASK_SIZE_64) > +#define DEFAULT_MAP_WINDOW (test_thread_flag(TIF_32BIT) ? \ > + TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64) > #else > #define TASK_SIZE TASK_SIZE_64 > +#define DEFAULT_MAP_WINDOW DEFAULT_MAP_WINDOW_64 > #endif /* CONFIG_COMPAT */ > > -#define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4)) > +#define TASK_UNMAPPED_BASE (PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4)) > +#define STACK_TOP_MAX DEFAULT_MAP_WINDOW_64 > > -#define STACK_TOP_MAX TASK_SIZE_64 > #ifdef CONFIG_COMPAT > #define AARCH32_VECTORS_BASE 0xffff0000 > #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \ > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index 9d9582cac6c4..e5a1dc0beef9 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -609,7 +609,7 @@ void __init mem_init(void) > * detected at build time already. > */ > #ifdef CONFIG_COMPAT > - BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); > + BUILD_BUG_ON(TASK_SIZE_32 > DEFAULT_MAP_WINDOW_64); > #endif Since you are at this, can you please remove the useless white space (I guess it was there before when we had more BUILD_BUG_ONs). > diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c > index 30ac0c975f8a..d1ec7136e3e1 100644 > --- a/drivers/firmware/efi/libstub/arm-stub.c > +++ b/drivers/firmware/efi/libstub/arm-stub.c > @@ -33,7 +33,7 @@ > #define EFI_RT_VIRTUAL_SIZE SZ_512M > > #ifdef CONFIG_ARM64 > -# define EFI_RT_VIRTUAL_LIMIT TASK_SIZE_64 > +# define EFI_RT_VIRTUAL_LIMIT DEFAULT_MAP_WINDOW_64 > #else > # define EFI_RT_VIRTUAL_LIMIT TASK_SIZE > #endif Just curious, would anything happen if we leave this to TASK_SIZE_64? -- Catalin