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To: Thierry Reding <thierry.reding@gmail.com>, Minjie Du <duminjie@vivo.com>,
 linux-tegra@vger.kernel.org, kernel-janitors@vger.kernel.org,
 iommu@lists.linux.dev, =?UTF-8?B?SsO2cmcgUsO2ZGVs?= <joro@8bytes.org>,
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Cc: opensource.kernel@vivo.com, LKML <linux-kernel@vger.kernel.org>
References: <ZK6a-f2Se3HWjU7D@orome>
Subject: Re: [PATCH] iommu: fix parameter check in tegra_smmu_debugfs_init()
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From: Markus Elfring <Markus.Elfring@web.de>
In-Reply-To: <ZK6a-f2Se3HWjU7D@orome>
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=E2=80=A6
> > +++ b/drivers/iommu/tegra-smmu.c
> > @@ -1056,7 +1056,7 @@ DEFINE_SHOW_ATTRIBUTE(tegra_smmu_clients);
> >  static void tegra_smmu_debugfs_init(struct tegra_smmu *smmu)
> >  {
> >  	smmu->debugfs =3D debugfs_create_dir("smmu", NULL);
> > -	if (!smmu->debugfs)
> > +	if (IS_ERR(smmu->debugfs))
> >  		return;
>
> I think we can just drop the error check altogether since
> debugfs_create_file() will simply return early if smmu->debugfs is an
> error pointer.

I find this explanation confusing.
Can consistent error detection matter also at this source code place?

Regards,
Markus