Am 18.02.2019 15:24, schrieb Dan Carpenter:
> On Mon, Feb 18, 2019 at 01:42:02PM +0100, Walter Harms wrote:
>> Am 18.02.2019 10:37, schrieb Dan Carpenter:
>>> On Sat, Feb 16, 2019 at 05:27:16PM +0100, Walter Harms wrote:
>>>> Am 16.02.2019 15:44, schrieb Colin King:
>>>>> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>>>
>>>>> Currently m_sg->baseaddr_h (a 32 bit unsigned int) is being shifted by a
>>>>> total of 32 bits; this always produces a 0 result. Fix this by casting
>>>>> it to a dma_addr_t (a 64 bit unsigned int) before performing the shift.
>>>>>
>>>>> Detected by CoverityScan, CID#147270 ("Operands don't affect result")
>>>>>
>>>>> Fixes: f0c568a478f0 ("[SCSI] mvumi: Add Marvell UMI driver")
>>>>> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>>>>> ---
>>>>> drivers/scsi/mvumi.c | 2 +-
>>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/scsi/mvumi.c b/drivers/scsi/mvumi.c
>>>>> index 36f64205ecfa..d3582accfd09 100644
>>>>> --- a/drivers/scsi/mvumi.c
>>>>> +++ b/drivers/scsi/mvumi.c
>>>>> @@ -313,7 +313,7 @@ static void mvumi_delete_internal_cmd(struct mvumi_hba
>>>>> *mhba,
>>>>> sgd_getsz(mhba, m_sg, size);
>>>>>
>>>>> phy_addr = (dma_addr_t) m_sg->baseaddr_l |
>>>>> - (dma_addr_t) ((m_sg->baseaddr_h << 16) << 16);
>>>>> + (((dma_addr_t) m_sg->baseaddr_h << 16) << 16);
>>>>>
>>>>> dma_free_coherent(&mhba->pdev->dev, size, cmd->data_buf,
>>>>> phy_addr);
>>>>
>>>> i would suggest to try a version with less casts to make it more readable
>>>> like this untested suggestion:
>>>>
>>>> phy_addr =(m_sg->baseaddr_h << 16)| m_sg->baseaddr_l;
>>>> phy_addr <<= 16;
>>>>
>>>
>>> That would be a behavior change but it also might be a bugfix? Why
>>> doesn't the code just do:
>>>
>>> phy_addr = ((dma_addr_t)m_sg->baseaddr_h << 32) | m_sg->baseaddr_l;
>>>
>>
>> phy_addr = ((dma_addr_t)m_sg->baseaddr_h << 32) | m_sg->baseaddr_l<<16;
> ^^^^
> In the original code, we don't do this shift.
>
You are right, my bad, sorry
my brain made it into 16bit values.
on the other side it shows my point that things must be obvious as possible,
re,
wh
