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Subject: Re: [PATCH v4 2/2] iommu/tegra-smmu: Expand mutex protection range
From:   Dmitry Osipenko <digetx@gmail.com>
To:     Nicolin Chen <nicoleotsuka@gmail.com>, thierry.reding@gmail.com,
        joro@8bytes.org
Cc:     vdumpa@nvidia.com, jonathanh@nvidia.com,
        linux-tegra@vger.kernel.org, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org, hch@infradead.org
References: <20200929061325.10197-1-nicoleotsuka@gmail.com>
 <20200929061325.10197-3-nicoleotsuka@gmail.com>
 <184163e9-01d4-dcc5-0adf-a3d175e56f16@gmail.com>
Message-ID: <7bcf39ad-a254-7601-af44-c05805113930@gmail.com>
Date:   Sat, 3 Oct 2020 17:28:04 +0300
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29.09.2020 20:42, Dmitry Osipenko пишет:
> 29.09.2020 09:13, Nicolin Chen пишет:
>> This is used to protect potential race condition at use_count.
>> since probes of client drivers, calling attach_dev(), may run
>> concurrently.
>>
>> Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
>> ---
> 
> It's always better not to mix success and error code paths in order to
> keep code readable, but not a big deal in the case of this particular
> patch since the changed code is quite simple. Please try to avoid doing
> this in the future patches.
> 
> Also, please note that in general it's better to use locked/unlocked
> versions for the functions like it's already done for
> tegra_smmu_map/unmap, this will remove the need to maintain lockings in
> the code. The code touched by this patch doesn't have complicated code
> paths, so it's good enough to me.
> 
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
> 

Tested-by: Dmitry Osipenko <digetx@gmail.com>