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From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     kuba@kernel.org
Cc:     vburru@marvell.com, aayarekar@marvell.com, davem@davemloft.net,
        edumazet@google.com, pabeni@redhat.com, sburla@marvell.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: Re: [PATCH] octeon_ep: Add missing check for ioremap
Date:   Thu, 15 Jun 2023 11:24:31 +0800
Message-Id: <20230615032431.48930-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
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On Thu, 15 Jun 2023 03:53:04 +0800 Jakub Kicinski wrote:
> On Wed, 14 Jun 2023 11:23:47 +0800 Jiasheng Jiang wrote:
>> @@ -981,6 +981,9 @@ int octep_device_setup(struct octep_device *oct)
>>  		oct->mmio[i].hw_addr =
>>  			ioremap(pci_resource_start(oct->pdev, i * 2),
>>  				pci_resource_len(oct->pdev, i * 2));
>> +		if (!oct->mmio[i].hw_addr)
>> +			goto unsupported_dev;
>> +
>>  		oct->mmio[i].mapped = 1;
>>  	}
>>  
>> @@ -1015,8 +1018,8 @@ int octep_device_setup(struct octep_device *oct)
>>  	return 0;
>>  
>>  unsupported_dev:
>> -	for (i = 0; i < OCTEP_MMIO_REGIONS; i++)
>> -		iounmap(oct->mmio[i].hw_addr);
>> +	for (j = 0; j < i; j++)
>> +		iounmap(oct->mmio[j].hw_addr);
> 
> Assuming @i is not changed by the rest of the function is a bit fragile.
> 
> Better way of handling this situation is:
> 
> unsupported_dev:
> 	i = OCTEP_MMIO_REGIONS;
> unmap_prev:
> 	while (i--)
> 		iounmap(oct->mmio[i].hw_addr);
> 
> and jump to unmap_prev

Fine, I will submit a v2 to fix it.

Thanks,
Jiasheng