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* [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags
@ 2020-05-06  3:07 Samuel Zou
  2020-05-06  3:19 ` Joe Perches
  0 siblings, 1 reply; 5+ messages in thread
From: Samuel Zou @ 2020-05-06  3:07 UTC (permalink / raw)
  To: johannes.berg, emmanuel.grumbach, luciano.coelho, linuxwifi,
	kvalo, davem
  Cc: linux-wireless, netdev, linux-kernel, Samuel Zou

This silences the following coccinelle warning:

"WARNING: sum of probable bitmasks, consider |"

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Samuel Zou <zou_wei@huawei.com>
---
 drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
index a0daae0..6d9bf9f 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -109,9 +109,9 @@ void iwl_trans_pcie_dump_regs(struct iwl_trans *trans)
 
 	/* Alloc a max size buffer */
 	alloc_size = PCI_ERR_ROOT_ERR_SRC +  4 + PREFIX_LEN;
-	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE + PREFIX_LEN);
-	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE + PREFIX_LEN);
-	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE + PREFIX_LEN);
+	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE | PREFIX_LEN);
+	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE | PREFIX_LEN);
+	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE | PREFIX_LEN);
 
 	buf = kmalloc(alloc_size, GFP_ATOMIC);
 	if (!buf)
-- 
2.6.2


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags
  2020-05-06  3:07 [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags Samuel Zou
@ 2020-05-06  3:19 ` Joe Perches
  2020-05-06 13:51   ` Luciano Coelho
  0 siblings, 1 reply; 5+ messages in thread
From: Joe Perches @ 2020-05-06  3:19 UTC (permalink / raw)
  To: Samuel Zou, johannes.berg, emmanuel.grumbach, luciano.coelho,
	linuxwifi, kvalo, davem
  Cc: linux-wireless, netdev, linux-kernel

On Wed, 2020-05-06 at 11:07 +0800, Samuel Zou wrote:
> This silences the following coccinelle warning:
> 
> "WARNING: sum of probable bitmasks, consider |"

I suggest instead ignoring bad and irrelevant warnings.

PREFIX_LEN is 32 not 0x20 or BIT(5)
PCI_DUMP_SIZE is 352

> diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
[]
> @@ -109,9 +109,9 @@ void iwl_trans_pcie_dump_regs(struct iwl_trans *trans)
>  
>  	/* Alloc a max size buffer */
>  	alloc_size = PCI_ERR_ROOT_ERR_SRC +  4 + PREFIX_LEN;
> -	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE + PREFIX_LEN);
> -	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE + PREFIX_LEN);
> -	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE + PREFIX_LEN);
> +	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE | PREFIX_LEN);
> +	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE | PREFIX_LEN);
> +	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE | PREFIX_LEN);
>  
>  	buf = kmalloc(alloc_size, GFP_ATOMIC);
>  	if (!buf)


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags
  2020-05-06  3:19 ` Joe Perches
@ 2020-05-06 13:51   ` Luciano Coelho
  2020-05-06 15:15     ` Joe Perches
  0 siblings, 1 reply; 5+ messages in thread
From: Luciano Coelho @ 2020-05-06 13:51 UTC (permalink / raw)
  To: Joe Perches, Samuel Zou, johannes.berg, emmanuel.grumbach,
	linuxwifi, kvalo, davem
  Cc: linux-wireless, netdev, linux-kernel

On Tue, 2020-05-05 at 20:19 -0700, Joe Perches wrote:
> On Wed, 2020-05-06 at 11:07 +0800, Samuel Zou wrote:
> > This silences the following coccinelle warning:
> > 
> > "WARNING: sum of probable bitmasks, consider |"
> 
> I suggest instead ignoring bad and irrelevant warnings.
> 
> PREFIX_LEN is 32 not 0x20 or BIT(5)
> PCI_DUMP_SIZE is 352
> 
> > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
> []
> > @@ -109,9 +109,9 @@ void iwl_trans_pcie_dump_regs(struct iwl_trans *trans)
> >  
> >  	/* Alloc a max size buffer */
> >  	alloc_size = PCI_ERR_ROOT_ERR_SRC +  4 + PREFIX_LEN;
> > -	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE + PREFIX_LEN);
> > -	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE + PREFIX_LEN);
> > -	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE + PREFIX_LEN);
> > +	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE | PREFIX_LEN);
> > +	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE | PREFIX_LEN);
> > +	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE | PREFIX_LEN);
> >  
> >  	buf = kmalloc(alloc_size, GFP_ATOMIC);
> >  	if (!buf)

Yeah, those macros are clearly not bitmasks.  I'm dropping this patch.

--
Cheers,
Luca.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags
  2020-05-06 13:51   ` Luciano Coelho
@ 2020-05-06 15:15     ` Joe Perches
  2020-05-07  4:10       ` Samuel Zou
  0 siblings, 1 reply; 5+ messages in thread
From: Joe Perches @ 2020-05-06 15:15 UTC (permalink / raw)
  To: Luciano Coelho, Samuel Zou, johannes.berg, emmanuel.grumbach,
	linuxwifi, kvalo, davem, Julia Lawall
  Cc: linux-wireless, netdev, linux-kernel, cocci

On Wed, 2020-05-06 at 16:51 +0300, Luciano Coelho wrote:
> On Tue, 2020-05-05 at 20:19 -0700, Joe Perches wrote:
> > On Wed, 2020-05-06 at 11:07 +0800, Samuel Zou wrote:
> > > This silences the following coccinelle warning:
> > > 
> > > "WARNING: sum of probable bitmasks, consider |"
> > 
> > I suggest instead ignoring bad and irrelevant warnings.
> > 
> > PREFIX_LEN is 32 not 0x20 or BIT(5)
> > PCI_DUMP_SIZE is 352
> > 
> > > diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
> > []
> > > @@ -109,9 +109,9 @@ void iwl_trans_pcie_dump_regs(struct iwl_trans *trans)
> > >  
> > >  	/* Alloc a max size buffer */
> > >  	alloc_size = PCI_ERR_ROOT_ERR_SRC +  4 + PREFIX_LEN;
> > > -	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE + PREFIX_LEN);
> > > -	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE + PREFIX_LEN);
> > > -	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE + PREFIX_LEN);
> > > +	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE | PREFIX_LEN);
> > > +	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE | PREFIX_LEN);
> > > +	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE | PREFIX_LEN);
> > >  
> > >  	buf = kmalloc(alloc_size, GFP_ATOMIC);
> > >  	if (!buf)
> 
> Yeah, those macros are clearly not bitmasks.  I'm dropping this patch.

Can the cocci script that generated this warning

scripts/coccinelle/misc/orplus.cocci

be dropped or improved to validate the likelihood that
the defines or constants used are more likely than
not are bit values?

Maybe these should be defined as hex or BIT or BIT_ULL
or GENMASK or the like?


Right now it seems it just tests for two constants.



^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags
  2020-05-06 15:15     ` Joe Perches
@ 2020-05-07  4:10       ` Samuel Zou
  0 siblings, 0 replies; 5+ messages in thread
From: Samuel Zou @ 2020-05-07  4:10 UTC (permalink / raw)
  To: Joe Perches, Luciano Coelho, johannes.berg, emmanuel.grumbach,
	linuxwifi, kvalo, davem, Julia Lawall
  Cc: linux-wireless, netdev, linux-kernel, cocci

Both of you are right.
I neglected, and this patch is wrong.

Thanks.

On 2020/5/6 23:15, Joe Perches wrote:
> On Wed, 2020-05-06 at 16:51 +0300, Luciano Coelho wrote:
>> On Tue, 2020-05-05 at 20:19 -0700, Joe Perches wrote:
>>> On Wed, 2020-05-06 at 11:07 +0800, Samuel Zou wrote:
>>>> This silences the following coccinelle warning:
>>>>
>>>> "WARNING: sum of probable bitmasks, consider |"
>>>
>>> I suggest instead ignoring bad and irrelevant warnings.
>>>
>>> PREFIX_LEN is 32 not 0x20 or BIT(5)
>>> PCI_DUMP_SIZE is 352
>>>
>>>> diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
>>> []
>>>> @@ -109,9 +109,9 @@ void iwl_trans_pcie_dump_regs(struct iwl_trans *trans)
>>>>   
>>>>   	/* Alloc a max size buffer */
>>>>   	alloc_size = PCI_ERR_ROOT_ERR_SRC +  4 + PREFIX_LEN;
>>>> -	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE + PREFIX_LEN);
>>>> -	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE + PREFIX_LEN);
>>>> -	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE + PREFIX_LEN);
>>>> +	alloc_size = max_t(u32, alloc_size, PCI_DUMP_SIZE | PREFIX_LEN);
>>>> +	alloc_size = max_t(u32, alloc_size, PCI_MEM_DUMP_SIZE | PREFIX_LEN);
>>>> +	alloc_size = max_t(u32, alloc_size, PCI_PARENT_DUMP_SIZE | PREFIX_LEN);
>>>>   
>>>>   	buf = kmalloc(alloc_size, GFP_ATOMIC);
>>>>   	if (!buf)
>>
>> Yeah, those macros are clearly not bitmasks.  I'm dropping this patch.
> 
> Can the cocci script that generated this warning
> 
> scripts/coccinelle/misc/orplus.cocci
> 
> be dropped or improved to validate the likelihood that
> the defines or constants used are more likely than
> not are bit values?
> 
> Maybe these should be defined as hex or BIT or BIT_ULL
> or GENMASK or the like?
> 
> 
> Right now it seems it just tests for two constants.
> 
> 
> 
> .
> 


^ permalink raw reply	[flat|nested] 5+ messages in thread

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Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2020-05-06  3:07 [PATCH -next] iwlwifi: pcie: Use bitwise instead of arithmetic operator for flags Samuel Zou
2020-05-06  3:19 ` Joe Perches
2020-05-06 13:51   ` Luciano Coelho
2020-05-06 15:15     ` Joe Perches
2020-05-07  4:10       ` Samuel Zou

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