From: Colin King <hidden> Date: 2017-08-23 15:39:41
From: Colin Ian King <redacted>
The comparison of hw_ioctxt.rx_buf_sz_idx == -1 is always false because
rx_buf_sz_idx is a uint16_t. Fix this by explicitly casting -1 to uint16_t.
Detected by CoverityScan, CID#1454559 ("Operands don't affect result")
Signed-off-by: Colin Ian King <redacted>
---
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
From: Colin Ian King <redacted>
The comparison of hw_ioctxt.rx_buf_sz_idx == -1 is always false because
rx_buf_sz_idx is a uint16_t. Fix this by explicitly casting -1 to uint16_t.
Detected by CoverityScan, CID#1454559 ("Operands don't affect result")
Signed-off-by: Colin Ian King <redacted>
---
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -352,7 +352,7 @@ static int set_hw_ioctxt(struct hinic_hwdev *hwdev, unsigned int rq_depth,}}-if(hw_ioctxt.rx_buf_sz_idx==-1)+if(hw_ioctxt.rx_buf_sz_idx==(uint16_t)-1)return-EINVAL;hw_ioctxt.sq_depth=ilog2(sq_depth);
Many thanks, Colin.
I prefer to avoid casting when possible, what do you think about replacing the condition by:
if (rx_buf_sz_table[i].sz != HINIC_RX_BUF_SZ)
return -EINVAL;
From: Colin Ian King <hidden> Date: 2017-08-24 08:54:07
On 24/08/17 09:48, Aviad Krawczyk wrote:
On 8/23/2017 6:39 PM, Colin King wrote:
quoted
From: Colin Ian King <redacted>
The comparison of hw_ioctxt.rx_buf_sz_idx == -1 is always false because
rx_buf_sz_idx is a uint16_t. Fix this by explicitly casting -1 to uint16_t.
Detected by CoverityScan, CID#1454559 ("Operands don't affect result")
Signed-off-by: Colin Ian King <redacted>
---
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -352,7 +352,7 @@ static int set_hw_ioctxt(struct hinic_hwdev *hwdev, unsigned int rq_depth,}}-if(hw_ioctxt.rx_buf_sz_idx==-1)+if(hw_ioctxt.rx_buf_sz_idx==(uint16_t)-1)return-EINVAL;hw_ioctxt.sq_depth=ilog2(sq_depth);
Many thanks, Colin.
I prefer to avoid casting when possible, what do you think about replacing the condition by:
if (rx_buf_sz_table[i].sz != HINIC_RX_BUF_SZ)
return -EINVAL;
Does that work as expected when rx_buf_sz_table[i].sz == -1?
From: Dan Carpenter <hidden> Date: 2017-08-24 09:30:16
On Thu, Aug 24, 2017 at 09:54:03AM +0100, Colin Ian King wrote:
On 24/08/17 09:48, Aviad Krawczyk wrote:
quoted
On 8/23/2017 6:39 PM, Colin King wrote:
quoted
From: Colin Ian King <redacted>
The comparison of hw_ioctxt.rx_buf_sz_idx == -1 is always false because
rx_buf_sz_idx is a uint16_t. Fix this by explicitly casting -1 to uint16_t.
Detected by CoverityScan, CID#1454559 ("Operands don't affect result")
Signed-off-by: Colin Ian King <redacted>
---
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -352,7 +352,7 @@ static int set_hw_ioctxt(struct hinic_hwdev *hwdev, unsigned int rq_depth,}}-if(hw_ioctxt.rx_buf_sz_idx==-1)+if(hw_ioctxt.rx_buf_sz_idx==(uint16_t)-1)return-EINVAL;hw_ioctxt.sq_depth=ilog2(sq_depth);
Many thanks, Colin.
I prefer to avoid casting when possible, what do you think about replacing the condition by:
if (rx_buf_sz_table[i].sz != HINIC_RX_BUF_SZ)
return -EINVAL;
Does that work as expected when rx_buf_sz_table[i].sz == -1?
No it doesn't. Please, don't ask rhetorical questions. I have a
toddler and I constantly ask him toddler level questions and it drives
me nuts that all the adults in the room will answer me... "Yes, I
already know that's a cow. I was quizing my son. But thank you!"
Meanwhile I can't resist answering questions myself...
The code looks like this:
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c
345 hw_ioctxt.rq_depth = ilog2(rq_depth);
346
347 for (i = 0; ; i++) {
348 if ((rx_buf_sz_table[i].sz == HINIC_RX_BUF_SZ) ||
349 (rx_buf_sz_table[i].sz == -1)) {
350 hw_ioctxt.rx_buf_sz_idx = rx_buf_sz_table[i].idx;
351 break;
352 }
353 }
354
355 if (hw_ioctxt.rx_buf_sz_idx == -1)
356 return -EINVAL;
357
The loop doesn't make sense. We are looping through rx_buf_sz_table[]
until we hit 2048 or -1. But 2048 comes first so we always get there
and break.
We may as well replace all that code with:
hw_ioctxt.rx_buf_sz_idx = 11;
Something is very wrong.
regards,
dan carpenter
On Thu, Aug 24, 2017 at 09:54:03AM +0100, Colin Ian King wrote:
quoted
On 24/08/17 09:48, Aviad Krawczyk wrote:
quoted
On 8/23/2017 6:39 PM, Colin King wrote:
quoted
From: Colin Ian King <redacted>
The comparison of hw_ioctxt.rx_buf_sz_idx == -1 is always false because
rx_buf_sz_idx is a uint16_t. Fix this by explicitly casting -1 to uint16_t.
Detected by CoverityScan, CID#1454559 ("Operands don't affect result")
Signed-off-by: Colin Ian King <redacted>
---
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -352,7 +352,7 @@ static int set_hw_ioctxt(struct hinic_hwdev *hwdev, unsigned int rq_depth,}}-if(hw_ioctxt.rx_buf_sz_idx==-1)+if(hw_ioctxt.rx_buf_sz_idx==(uint16_t)-1)return-EINVAL;hw_ioctxt.sq_depth=ilog2(sq_depth);
Many thanks, Colin.
I prefer to avoid casting when possible, what do you think about replacing the condition by:
if (rx_buf_sz_table[i].sz != HINIC_RX_BUF_SZ)
return -EINVAL;
Does that work as expected when rx_buf_sz_table[i].sz == -1?
No it doesn't. Please, don't ask rhetorical questions. I have a
toddler and I constantly ask him toddler level questions and it drives
me nuts that all the adults in the room will answer me... "Yes, I
already know that's a cow. I was quizing my son. But thank you!"
Meanwhile I can't resist answering questions myself...
The code looks like this:
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c
345 hw_ioctxt.rq_depth = ilog2(rq_depth);
346
347 for (i = 0; ; i++) {
348 if ((rx_buf_sz_table[i].sz == HINIC_RX_BUF_SZ) ||
349 (rx_buf_sz_table[i].sz == -1)) {
350 hw_ioctxt.rx_buf_sz_idx = rx_buf_sz_table[i].idx;
351 break;
352 }
353 }
354
355 if (hw_ioctxt.rx_buf_sz_idx == -1)
356 return -EINVAL;
357
The loop doesn't make sense. We are looping through rx_buf_sz_table[]
until we hit 2048 or -1. But 2048 comes first so we always get there
and break.
We may as well replace all that code with:
hw_ioctxt.rx_buf_sz_idx = 11;
Something is very wrong.
regards,
dan carpenter
.
Hi Dan,
What if HINIC_RX_BUF_SZ is changed to another value?
The test checks if the HINIC_RX_BUF_SZ is in the table, if not return -EINVAL.
Therefore I think the check of rx_buf_sz_table[i].sz != HINIC_RX_BUF_SZ is better.
Aviad
From: David Miller <davem@davemloft.net> Date: 2017-08-24 21:32:33
From: Colin King <redacted>
Date: Wed, 23 Aug 2017 16:39:36 +0100
quoted hunk
From: Colin Ian King <redacted>
The comparison of hw_ioctxt.rx_buf_sz_idx == -1 is always false because
rx_buf_sz_idx is a uint16_t. Fix this by explicitly casting -1 to uint16_t.
Detected by CoverityScan, CID#1454559 ("Operands don't affect result")
Signed-off-by: Colin Ian King <redacted>
---
drivers/net/ethernet/huawei/hinic/hinic_hw_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -352,7 +352,7 @@ static int set_hw_ioctxt(struct hinic_hwdev *hwdev, unsigned int rq_depth,}}-if(hw_ioctxt.rx_buf_sz_idx==-1)+if(hw_ioctxt.rx_buf_sz_idx==(uint16_t)-1)return-EINVAL;hw_ioctxt.sq_depth=ilog2(sq_depth);
This is really silly.
The code in question is trying to convert a size (HINIC_RX_BUF_SZ)
into a table index, using a loop.
It should just compute this at compile time and do away with this
overly confusing code.
Even a switch statement would be much better and the compiler
would optimize the whole away into a single assignment in
the generated code.