diff mbox series

[v2] PCI: rpaphp: Avoid a sometimes-uninitialized warning

Message ID 20190603221157.58502-1-natechancellor@gmail.com (mailing list archive)
State Mainlined, archived
Commit 0df3e42167caaf9f8c7b64de3da40a459979afe8
Headers show
Series [v2] PCI: rpaphp: Avoid a sometimes-uninitialized warning | expand

Commit Message

Nathan Chancellor June 3, 2019, 10:11 p.m. UTC
When building with -Wsometimes-uninitialized, clang warns:

drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
used uninitialized whenever 'for' loop exits because its condition is
false [-Wsometimes-uninitialized]
        for (j = 0; j < entries; j++) {
                    ^~~~~~~~~~~
drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
here
        if (fndit)
            ^~~~~
drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
it is always true
        for (j = 0; j < entries; j++) {
                    ^~~~~~~~~~~
drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
'fndit' to silence this warning
        int j, fndit;
                    ^
                     = 0

fndit is only used to gate a sprintf call, which can be moved into the
loop to simplify the code and eliminate the local variable, which will
fix this warning.

Link: https://github.com/ClangBuiltLinux/linux/issues/504
Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---

v1 -> v2:

* Eliminate fndit altogether by shuffling the sprintf call into the for
  loop and changing the if conditional, as suggested by Nick.

 drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

Comments

Tyrel Datwyler June 4, 2019, 12:03 a.m. UTC | #1
On 06/03/2019 03:11 PM, Nathan Chancellor wrote:
> When building with -Wsometimes-uninitialized, clang warns:
> 
> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
> used uninitialized whenever 'for' loop exits because its condition is
> false [-Wsometimes-uninitialized]
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
> here
>         if (fndit)
>             ^~~~~
> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
> it is always true
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
> 'fndit' to silence this warning
>         int j, fndit;
>                     ^
>                      = 0
> 
> fndit is only used to gate a sprintf call, which can be moved into the
> loop to simplify the code and eliminate the local variable, which will
> fix this warning.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/504
> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Acked-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Nathan Chancellor June 27, 2019, 7:18 p.m. UTC | #2
On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
> When building with -Wsometimes-uninitialized, clang warns:
> 
> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
> used uninitialized whenever 'for' loop exits because its condition is
> false [-Wsometimes-uninitialized]
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
> here
>         if (fndit)
>             ^~~~~
> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
> it is always true
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
> 'fndit' to silence this warning
>         int j, fndit;
>                     ^
>                      = 0
> 
> fndit is only used to gate a sprintf call, which can be moved into the
> loop to simplify the code and eliminate the local variable, which will
> fix this warning.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/504
> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
> 
> v1 -> v2:
> 
> * Eliminate fndit altogether by shuffling the sprintf call into the for
>   loop and changing the if conditional, as suggested by Nick.
> 
>  drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
>  1 file changed, 7 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
> index bcd5d357ca23..c3899ee1db99 100644
> --- a/drivers/pci/hotplug/rpaphp_core.c
> +++ b/drivers/pci/hotplug/rpaphp_core.c
> @@ -230,7 +230,7 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>  	struct of_drc_info drc;
>  	const __be32 *value;
>  	char cell_drc_name[MAX_DRC_NAME_LEN];
> -	int j, fndit;
> +	int j;
>  
>  	info = of_find_property(dn->parent, "ibm,drc-info", NULL);
>  	if (info == NULL)
> @@ -245,17 +245,13 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>  
>  		/* Should now know end of current entry */
>  
> -		if (my_index > drc.last_drc_index)
> -			continue;
> -
> -		fndit = 1;
> -		break;
> +		/* Found it */
> +		if (my_index <= drc.last_drc_index) {
> +			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
> +				my_index);
> +			break;
> +		}
>  	}
> -	/* Found it */
> -
> -	if (fndit)
> -		sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
> -			my_index);
>  
>  	if (((drc_name == NULL) ||
>  	     (drc_name && !strcmp(drc_name, cell_drc_name))) &&
> -- 
> 2.22.0.rc3
> 

Gentle ping, can someone pick this up?

Cheers,
Nathan
Joel Savitz June 28, 2019, 2:57 a.m. UTC | #3
>On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
>> When building with -Wsometimes-uninitialized, clang warns:
>> 
>> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
>> used uninitialized whenever 'for' loop exits because its condition is
>> false [-Wsometimes-uninitialized]
>>         for (j = 0; j < entries; j++) {
>>                     ^~~~~~~~~~~
>> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
>> here
>>         if (fndit)
>>             ^~~~~
>> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
>> it is always true
>>         for (j = 0; j < entries; j++) {
>>                     ^~~~~~~~~~~
>> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
>> 'fndit' to silence this warning
>>         int j, fndit;
>>                     ^
>>                      = 0
>> 
>> fndit is only used to gate a sprintf call, which can be moved into the
>> loop to simplify the code and eliminate the local variable, which will
>> fix this warning.
>> 
>> Link: https://github.com/ClangBuiltLinux/linux/issues/504
>> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
>> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
>> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
>> ---
>> 
>> v1 -> v2:
>> 
>> * Eliminate fndit altogether by shuffling the sprintf call into the for
>>   loop and changing the if conditional, as suggested by Nick.
> 
>>  drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
>>  1 file changed, 7 insertions(+), 11 deletions(-)

>> Gentle ping, can someone pick this up?

Looks a good simplification of somewhat convoluted control flow.

Acked-by: Joel Savitz <jsavitz@redhat.com>
Nathan Chancellor July 22, 2019, 2:43 a.m. UTC | #4
On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
> When building with -Wsometimes-uninitialized, clang warns:
> 
> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
> used uninitialized whenever 'for' loop exits because its condition is
> false [-Wsometimes-uninitialized]
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
> here
>         if (fndit)
>             ^~~~~
> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
> it is always true
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
> 'fndit' to silence this warning
>         int j, fndit;
>                     ^
>                      = 0
> 
> fndit is only used to gate a sprintf call, which can be moved into the
> loop to simplify the code and eliminate the local variable, which will
> fix this warning.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/504
> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
> 
> v1 -> v2:
> 
> * Eliminate fndit altogether by shuffling the sprintf call into the for
>   loop and changing the if conditional, as suggested by Nick.
> 
>  drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
>  1 file changed, 7 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
> index bcd5d357ca23..c3899ee1db99 100644
> --- a/drivers/pci/hotplug/rpaphp_core.c
> +++ b/drivers/pci/hotplug/rpaphp_core.c
> @@ -230,7 +230,7 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>  	struct of_drc_info drc;
>  	const __be32 *value;
>  	char cell_drc_name[MAX_DRC_NAME_LEN];
> -	int j, fndit;
> +	int j;
>  
>  	info = of_find_property(dn->parent, "ibm,drc-info", NULL);
>  	if (info == NULL)
> @@ -245,17 +245,13 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>  
>  		/* Should now know end of current entry */
>  
> -		if (my_index > drc.last_drc_index)
> -			continue;
> -
> -		fndit = 1;
> -		break;
> +		/* Found it */
> +		if (my_index <= drc.last_drc_index) {
> +			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
> +				my_index);
> +			break;
> +		}
>  	}
> -	/* Found it */
> -
> -	if (fndit)
> -		sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
> -			my_index);
>  
>  	if (((drc_name == NULL) ||
>  	     (drc_name && !strcmp(drc_name, cell_drc_name))) &&
> -- 
> 2.22.0.rc3
> 

Hi all,

Could someone please pick this up?

Thanks,
Nathan
Michael Ellerman July 22, 2019, 4:05 a.m. UTC | #5
Nathan Chancellor <natechancellor@gmail.com> writes:
> On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
>> When building with -Wsometimes-uninitialized, clang warns:
>> 
>> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
>> used uninitialized whenever 'for' loop exits because its condition is
>> false [-Wsometimes-uninitialized]
>>         for (j = 0; j < entries; j++) {
>>                     ^~~~~~~~~~~
>> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
>> here
>>         if (fndit)
>>             ^~~~~
>> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
>> it is always true
>>         for (j = 0; j < entries; j++) {
>>                     ^~~~~~~~~~~
>> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
>> 'fndit' to silence this warning
>>         int j, fndit;
>>                     ^
>>                      = 0
>> 
>> fndit is only used to gate a sprintf call, which can be moved into the
>> loop to simplify the code and eliminate the local variable, which will
>> fix this warning.
>> 
>> Link: https://github.com/ClangBuiltLinux/linux/issues/504
>> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
>> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
>> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
>> ---
>> 
>> v1 -> v2:
>> 
>> * Eliminate fndit altogether by shuffling the sprintf call into the for
>>   loop and changing the if conditional, as suggested by Nick.
>> 
>>  drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
>>  1 file changed, 7 insertions(+), 11 deletions(-)
>> 
>> diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
>> index bcd5d357ca23..c3899ee1db99 100644
>> --- a/drivers/pci/hotplug/rpaphp_core.c
>> +++ b/drivers/pci/hotplug/rpaphp_core.c
>> @@ -230,7 +230,7 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>>  	struct of_drc_info drc;
>>  	const __be32 *value;
>>  	char cell_drc_name[MAX_DRC_NAME_LEN];
>> -	int j, fndit;
>> +	int j;
>>  
>>  	info = of_find_property(dn->parent, "ibm,drc-info", NULL);
>>  	if (info == NULL)
>> @@ -245,17 +245,13 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>>  
>>  		/* Should now know end of current entry */
>>  
>> -		if (my_index > drc.last_drc_index)
>> -			continue;
>> -
>> -		fndit = 1;
>> -		break;
>> +		/* Found it */
>> +		if (my_index <= drc.last_drc_index) {
>> +			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
>> +				my_index);
>> +			break;
>> +		}
>>  	}
>> -	/* Found it */
>> -
>> -	if (fndit)
>> -		sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
>> -			my_index);
>>  
>>  	if (((drc_name == NULL) ||
>>  	     (drc_name && !strcmp(drc_name, cell_drc_name))) &&
>> -- 
>> 2.22.0.rc3
>> 
>
> Hi all,
>
> Could someone please pick this up?

I'll take it.

I was expecting Bjorn to take it as a PCI patch, but I realise now that
I merged that code in the first place so may as well take this too.

I'll put it in my next branch once that opens next week.

cheers
Bjorn Helgaas Aug. 2, 2019, 12:11 a.m. UTC | #6
On Mon, Jul 22, 2019 at 02:05:12PM +1000, Michael Ellerman wrote:
> Nathan Chancellor <natechancellor@gmail.com> writes:
> > On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
> >> When building with -Wsometimes-uninitialized, clang warns:
> >> 
> >> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
> >> used uninitialized whenever 'for' loop exits because its condition is
> >> false [-Wsometimes-uninitialized]
> >>         for (j = 0; j < entries; j++) {
> >>                     ^~~~~~~~~~~
> >> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
> >> here
> >>         if (fndit)
> >>             ^~~~~
> >> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
> >> it is always true
> >>         for (j = 0; j < entries; j++) {
> >>                     ^~~~~~~~~~~
> >> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
> >> 'fndit' to silence this warning
> >>         int j, fndit;
> >>                     ^
> >>                      = 0
> >> 
> >> fndit is only used to gate a sprintf call, which can be moved into the
> >> loop to simplify the code and eliminate the local variable, which will
> >> fix this warning.
> >> 
> >> Link: https://github.com/ClangBuiltLinux/linux/issues/504
> >> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
> >> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
> >> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> >> ---
> >> 
> >> v1 -> v2:
> >> 
> >> * Eliminate fndit altogether by shuffling the sprintf call into the for
> >>   loop and changing the if conditional, as suggested by Nick.
> >> 
> >>  drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
> >>  1 file changed, 7 insertions(+), 11 deletions(-)
> >> 
> >> diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
> >> index bcd5d357ca23..c3899ee1db99 100644
> >> --- a/drivers/pci/hotplug/rpaphp_core.c
> >> +++ b/drivers/pci/hotplug/rpaphp_core.c
> >> @@ -230,7 +230,7 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
> >>  	struct of_drc_info drc;
> >>  	const __be32 *value;
> >>  	char cell_drc_name[MAX_DRC_NAME_LEN];
> >> -	int j, fndit;
> >> +	int j;
> >>  
> >>  	info = of_find_property(dn->parent, "ibm,drc-info", NULL);
> >>  	if (info == NULL)
> >> @@ -245,17 +245,13 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
> >>  
> >>  		/* Should now know end of current entry */
> >>  
> >> -		if (my_index > drc.last_drc_index)
> >> -			continue;
> >> -
> >> -		fndit = 1;
> >> -		break;
> >> +		/* Found it */
> >> +		if (my_index <= drc.last_drc_index) {
> >> +			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
> >> +				my_index);
> >> +			break;
> >> +		}
> >>  	}
> >> -	/* Found it */
> >> -
> >> -	if (fndit)
> >> -		sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
> >> -			my_index);
> >>  
> >>  	if (((drc_name == NULL) ||
> >>  	     (drc_name && !strcmp(drc_name, cell_drc_name))) &&
> >> -- 
> >> 2.22.0.rc3
> >> 
> >
> > Hi all,
> >
> > Could someone please pick this up?
> 
> I'll take it.
> 
> I was expecting Bjorn to take it as a PCI patch, but I realise now that
> I merged that code in the first place so may as well take this too.
> 
> I'll put it in my next branch once that opens next week.

Sorry, I should have done something with this.  Did you take it,
Michael?  I don't see it in -next and haven't figured out where to
look in your git tree, so I can't tell.  Just let me know either way
so I know whether to drop this or apply it.

Bjorn
Michael Ellerman Aug. 2, 2019, 12:24 p.m. UTC | #7
Bjorn Helgaas <helgaas@kernel.org> writes:
> On Mon, Jul 22, 2019 at 02:05:12PM +1000, Michael Ellerman wrote:
>> Nathan Chancellor <natechancellor@gmail.com> writes:
>> > On Mon, Jun 03, 2019 at 03:11:58PM -0700, Nathan Chancellor wrote:
>> >> When building with -Wsometimes-uninitialized, clang warns:
>> >> 
>> >> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
>> >> used uninitialized whenever 'for' loop exits because its condition is
>> >> false [-Wsometimes-uninitialized]
>> >>         for (j = 0; j < entries; j++) {
>> >>                     ^~~~~~~~~~~
>> >> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
>> >> here
>> >>         if (fndit)
>> >>             ^~~~~
>> >> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
>> >> it is always true
>> >>         for (j = 0; j < entries; j++) {
>> >>                     ^~~~~~~~~~~
>> >> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
>> >> 'fndit' to silence this warning
>> >>         int j, fndit;
>> >>                     ^
>> >>                      = 0
>> >> 
>> >> fndit is only used to gate a sprintf call, which can be moved into the
>> >> loop to simplify the code and eliminate the local variable, which will
>> >> fix this warning.
>> >> 
>> >> Link: https://github.com/ClangBuiltLinux/linux/issues/504
>> >> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
>> >> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
>> >> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
>> >> ---
>> >> 
>> >> v1 -> v2:
>> >> 
>> >> * Eliminate fndit altogether by shuffling the sprintf call into the for
>> >>   loop and changing the if conditional, as suggested by Nick.
>> >> 
>> >>  drivers/pci/hotplug/rpaphp_core.c | 18 +++++++-----------
>> >>  1 file changed, 7 insertions(+), 11 deletions(-)
>> >> 
>> >> diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
>> >> index bcd5d357ca23..c3899ee1db99 100644
>> >> --- a/drivers/pci/hotplug/rpaphp_core.c
>> >> +++ b/drivers/pci/hotplug/rpaphp_core.c
>> >> @@ -230,7 +230,7 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>> >>  	struct of_drc_info drc;
>> >>  	const __be32 *value;
>> >>  	char cell_drc_name[MAX_DRC_NAME_LEN];
>> >> -	int j, fndit;
>> >> +	int j;
>> >>  
>> >>  	info = of_find_property(dn->parent, "ibm,drc-info", NULL);
>> >>  	if (info == NULL)
>> >> @@ -245,17 +245,13 @@ static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
>> >>  
>> >>  		/* Should now know end of current entry */
>> >>  
>> >> -		if (my_index > drc.last_drc_index)
>> >> -			continue;
>> >> -
>> >> -		fndit = 1;
>> >> -		break;
>> >> +		/* Found it */
>> >> +		if (my_index <= drc.last_drc_index) {
>> >> +			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
>> >> +				my_index);
>> >> +			break;
>> >> +		}
>> >>  	}
>> >> -	/* Found it */
>> >> -
>> >> -	if (fndit)
>> >> -		sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
>> >> -			my_index);
>> >>  
>> >>  	if (((drc_name == NULL) ||
>> >>  	     (drc_name && !strcmp(drc_name, cell_drc_name))) &&
>> >> -- 
>> >> 2.22.0.rc3
>> >> 
>> >
>> > Hi all,
>> >
>> > Could someone please pick this up?
>> 
>> I'll take it.
>> 
>> I was expecting Bjorn to take it as a PCI patch, but I realise now that
>> I merged that code in the first place so may as well take this too.
>> 
>> I'll put it in my next branch once that opens next week.
>
> Sorry, I should have done something with this.  Did you take it,
> Michael?  I don't see it in -next and haven't figured out where to
> look in your git tree, so I can't tell.  Just let me know either way
> so I know whether to drop this or apply it.

Yes I have it in my next-test, which will eventually become my next when
I get time to rebase it, test and push etc:

https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/log/?h=next-test

So no further action required on your part.

cheers
Michael Ellerman Aug. 10, 2019, 10:20 a.m. UTC | #8
On Mon, 2019-06-03 at 22:11:58 UTC, Nathan Chancellor wrote:
> When building with -Wsometimes-uninitialized, clang warns:
> 
> drivers/pci/hotplug/rpaphp_core.c:243:14: warning: variable 'fndit' is
> used uninitialized whenever 'for' loop exits because its condition is
> false [-Wsometimes-uninitialized]
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:256:6: note: uninitialized use occurs
> here
>         if (fndit)
>             ^~~~~
> drivers/pci/hotplug/rpaphp_core.c:243:14: note: remove the condition if
> it is always true
>         for (j = 0; j < entries; j++) {
>                     ^~~~~~~~~~~
> drivers/pci/hotplug/rpaphp_core.c:233:14: note: initialize the variable
> 'fndit' to silence this warning
>         int j, fndit;
>                     ^
>                      = 0
> 
> fndit is only used to gate a sprintf call, which can be moved into the
> loop to simplify the code and eliminate the local variable, which will
> fix this warning.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/504
> Fixes: 2fcf3ae508c2 ("hotplug/drc-info: Add code to search ibm,drc-info property")
> Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> Acked-by: Tyrel Datwyler <tyreld@linux.ibm.com>
> Acked-by: Joel Savitz <jsavitz@redhat.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/0df3e42167caaf9f8c7b64de3da40a459979afe8

cheers
diff mbox series

Patch

diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c
index bcd5d357ca23..c3899ee1db99 100644
--- a/drivers/pci/hotplug/rpaphp_core.c
+++ b/drivers/pci/hotplug/rpaphp_core.c
@@ -230,7 +230,7 @@  static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
 	struct of_drc_info drc;
 	const __be32 *value;
 	char cell_drc_name[MAX_DRC_NAME_LEN];
-	int j, fndit;
+	int j;
 
 	info = of_find_property(dn->parent, "ibm,drc-info", NULL);
 	if (info == NULL)
@@ -245,17 +245,13 @@  static int rpaphp_check_drc_props_v2(struct device_node *dn, char *drc_name,
 
 		/* Should now know end of current entry */
 
-		if (my_index > drc.last_drc_index)
-			continue;
-
-		fndit = 1;
-		break;
+		/* Found it */
+		if (my_index <= drc.last_drc_index) {
+			sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix,
+				my_index);
+			break;
+		}
 	}
-	/* Found it */
-
-	if (fndit)
-		sprintf(cell_drc_name, "%s%d", drc.drc_name_prefix, 
-			my_index);
 
 	if (((drc_name == NULL) ||
 	     (drc_name && !strcmp(drc_name, cell_drc_name))) &&