Re: [PATCH] iommu/arm-smmu: fix the module name for disable_bypass parameter - Russell King

From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
To: Li Yang <leoyang.li@nxp.com>
Cc: Will Deacon <will.deacon@arm.com>,
	linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
	Robin Murphy <robin.murphy@arm.com>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] iommu/arm-smmu: fix the module name for disable_bypass parameter
Date: Tue, 11 Feb 2020 23:45:36 +0000	[thread overview]
Message-ID: <20200211234536.GK25745@shell.armlinux.org.uk> (raw)
In-Reply-To: <1581464215-24777-1-git-send-email-leoyang.li@nxp.com>

On Tue, Feb 11, 2020 at 05:36:55PM -0600, Li Yang wrote:
> Since commit cd221bd24ff5 ("iommu/arm-smmu: Allow building as a module"),
> there is a side effect that the module name is changed from arm-smmu to
> arm-smmu-mod.  So the kernel parameter for disable_bypass need to be
> changed too.  Fix the Kconfig help and error message to the correct
> parameter name.

Hmm, this seems to be a user-visible change - so those of us who have
been booting with "arm-smmu.disable_bypass=0" now need to change that
depending on which kernel is being booted - which is not nice, and
makes the support side on platforms that need this kernel parameter
harder.

> 
> Signed-off-by: Li Yang <leoyang.li@nxp.com>
> ---
>  drivers/iommu/Kconfig    | 2 +-
>  drivers/iommu/arm-smmu.c | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index d2fade984999..fb54be903c60 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -415,7 +415,7 @@ config ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT
>  	  hardcode the bypass disable in the code.
>  
>  	  NOTE: the kernel command line parameter
> -	  'arm-smmu.disable_bypass' will continue to override this
> +	  'arm-smmu-mod.disable_bypass' will continue to override this
>  	  config.
>  
>  config ARM_SMMU_V3
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 16c4b87af42b..2ffe8ff04393 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -512,7 +512,7 @@ static irqreturn_t arm_smmu_global_fault(int irq, void *dev)
>  		if (IS_ENABLED(CONFIG_ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT) &&
>  		    (gfsr & ARM_SMMU_sGFSR_USF))
>  			dev_err(smmu->dev,
> -				"Blocked unknown Stream ID 0x%hx; boot with \"arm-smmu.disable_bypass=0\" to allow, but this may have security implications\n",
> +				"Blocked unknown Stream ID 0x%hx; boot with \"arm-smmu-mod.disable_bypass=0\" to allow, but this may have security implications\n",
>  				(u16)gfsynr1);
>  		else
>  			dev_err(smmu->dev,
> -- 
> 2.17.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 

-- 
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