Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <29f6d2c8-fc10-6120-1ce6-888db8db13dc@arm.com>
Date:   Tue, 16 May 2023 12:51:09 +0100
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:102.0) Gecko/20100101
 Thunderbird/102.10.1
Subject: Re: [PATCH v2] iommu: make IPMMU_VMSA dependencies more strict
Content-Language: en-GB
To:     Randy Dunlap <rdunlap@infradead.org>, linux-kernel@vger.kernel.org
Cc:     Geert Uytterhoeven <geert@linux-m68k.org>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        iommu@lists.linux.dev, Conor Dooley <conor@kernel.org>,
        Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
References: <20230330165817.21920-1-rdunlap@infradead.org>
From:   Robin Murphy <robin.murphy@arm.com>
In-Reply-To: <20230330165817.21920-1-rdunlap@infradead.org>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 2023-03-30 17:58, Randy Dunlap wrote:
> On riscv64, linux-next-20233030 (and for several days earlier),
> there is a kconfig warning:
> 
> WARNING: unmet direct dependencies detected for IOMMU_IO_PGTABLE_LPAE
>    Depends on [n]: IOMMU_SUPPORT [=y] && (ARM || ARM64 || COMPILE_TEST [=n]) && !GENERIC_ATOMIC64 [=n]
>    Selected by [y]:
>    - IPMMU_VMSA [=y] && IOMMU_SUPPORT [=y] && (ARCH_RENESAS [=y] || COMPILE_TEST [=n]) && !GENERIC_ATOMIC64 [=n]
> 
> and build errors:
> 
> riscv64-linux-ld: drivers/iommu/io-pgtable-arm.o: in function `.L140':
> io-pgtable-arm.c:(.init.text+0x1e8): undefined reference to `alloc_io_pgtable_ops'
> riscv64-linux-ld: drivers/iommu/io-pgtable-arm.o: in function `.L168':
> io-pgtable-arm.c:(.init.text+0xab0): undefined reference to `free_io_pgtable_ops'
> riscv64-linux-ld: drivers/iommu/ipmmu-vmsa.o: in function `.L140':
> ipmmu-vmsa.c:(.text+0xbc4): undefined reference to `free_io_pgtable_ops'
> riscv64-linux-ld: drivers/iommu/ipmmu-vmsa.o: in function `.L0 ':
> ipmmu-vmsa.c:(.text+0x145e): undefined reference to `alloc_io_pgtable_ops'
> 
> Add ARM || ARM64 || COMPILE_TEST dependencies to IPMMU_VMSA to prevent
> these issues, i.e., so that ARCH_RENESAS on RISC-V is not allowed.
> 
> This makes the ARCH dependencies become:
> 	depends on (ARCH_RENESAS && (ARM || ARM64)) || COMPILE_TEST
> but that can be a bit hard to read.

If it helps,

Reviewed-by: Robin Murphy <robin.murphy@arm.com>

> Fixes: 8292493c22c8 ("riscv: Kconfig.socs: Add ARCH_RENESAS kconfig option")
> Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
> Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Will Deacon <will@kernel.org>
> Cc: Robin Murphy <robin.murphy@arm.com>
> Cc: iommu@lists.linux.dev
> Cc: Conor Dooley <conor@kernel.org>
> Cc: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>   drivers/iommu/Kconfig |    1 +
>   1 file changed, 1 insertion(+)
> 
> diff -- a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -287,6 +287,7 @@ config EXYNOS_IOMMU_DEBUG
>   config IPMMU_VMSA
>   	bool "Renesas VMSA-compatible IPMMU"
>   	depends on ARCH_RENESAS || COMPILE_TEST
> +	depends on ARM || ARM64 || COMPILE_TEST
>   	depends on !GENERIC_ATOMIC64	# for IOMMU_IO_PGTABLE_LPAE
>   	select IOMMU_API
>   	select IOMMU_IO_PGTABLE_LPAE