Re: [PATCH -next] mm: Mark 'stack_vm_area' with __maybe_unused

2019-01-03 Thread Michal Hocko 
On Wed 02-01-19 19:40:15, YueHaibing wrote:
> On 2019/1/2 18:55, Dan Carpenter wrote:
> > On Fri, Dec 28, 2018 at 09:58:04AM +0100, Michal Hocko wrote:
> >> On Fri 28-12-18 02:46:30, YueHaibing wrote:
> >>> Fixes gcc '-Wunused-but-set-variable' warning when
> >>> CONFIG_VMAP_STACK is not set:
> >>
> >> Isn't this warning disabled? I can see the following
> >> # These warnings generated too much noise in a regular build.
> >> # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
> >> KBUILD_CFLAGS += -Wno-unused-but-set-variable
> >>
> >> in the main makefile. IMHO this warning doesn't really give us much.
> >>
> > 
> > It would be nice to enable that warning.  YueHaibing and Colin King have
> > been whittling away at the problematic code...
> > 
> > YueHaibing, how many of these warnings do we have remaining on an
> > allmodoconfig?
> 
> about 1300+

This is way too much. Is any of them actually pointing to a real bug?

-- 
Michal Hocko
SUSE Labs

Re: [PATCH -next] mm: Mark 'stack_vm_area' with __maybe_unused

2019-01-02 Thread YueHaibing 
On 2019/1/2 18:55, Dan Carpenter wrote:
> On Fri, Dec 28, 2018 at 09:58:04AM +0100, Michal Hocko wrote:
>> On Fri 28-12-18 02:46:30, YueHaibing wrote:
>>> Fixes gcc '-Wunused-but-set-variable' warning when
>>> CONFIG_VMAP_STACK is not set:
>>
>> Isn't this warning disabled? I can see the following
>> # These warnings generated too much noise in a regular build.
>> # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
>> KBUILD_CFLAGS += -Wno-unused-but-set-variable
>>
>> in the main makefile. IMHO this warning doesn't really give us much.
>>
> 
> It would be nice to enable that warning.  YueHaibing and Colin King have
> been whittling away at the problematic code...
> 
> YueHaibing, how many of these warnings do we have remaining on an
> allmodoconfig?

about 1300+

> 
> regards,
> dan carpenter
> 
> 
> .
>

Re: [PATCH -next] mm: Mark 'stack_vm_area' with __maybe_unused

2019-01-02 Thread Dan Carpenter 
On Fri, Dec 28, 2018 at 09:58:04AM +0100, Michal Hocko wrote:
> On Fri 28-12-18 02:46:30, YueHaibing wrote:
> > Fixes gcc '-Wunused-but-set-variable' warning when
> > CONFIG_VMAP_STACK is not set:
> 
> Isn't this warning disabled? I can see the following
> # These warnings generated too much noise in a regular build.
> # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
> KBUILD_CFLAGS += -Wno-unused-but-set-variable
> 
> in the main makefile. IMHO this warning doesn't really give us much.
> 

It would be nice to enable that warning.  YueHaibing and Colin King have
been whittling away at the problematic code...

YueHaibing, how many of these warnings do we have remaining on an
allmodoconfig?

regards,
dan carpenter

Re: [PATCH -next] mm: Mark 'stack_vm_area' with __maybe_unused

2018-12-28 Thread Michal Hocko 
On Fri 28-12-18 02:46:30, YueHaibing wrote:
> Fixes gcc '-Wunused-but-set-variable' warning when
> CONFIG_VMAP_STACK is not set:

Isn't this warning disabled? I can see the following
# These warnings generated too much noise in a regular build.
# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
KBUILD_CFLAGS += -Wno-unused-but-set-variable

in the main makefile. IMHO this warning doesn't really give us much.

> 
> kernel/fork.c: In function 'dup_task_struct':
> kernel/fork.c:843:20: warning:
>  variable 'stack_vm_area' set but not used [-Wunused-but-set-variable]
> 
> Signed-off-by: YueHaibing 
> ---
>  kernel/fork.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/fork.c b/kernel/fork.c
> index e2a5156..b38c392 100644
> --- a/kernel/fork.c
> +++ b/kernel/fork.c
> @@ -840,7 +840,7 @@ static struct task_struct *dup_task_struct(struct 
> task_struct *orig, int node)
>  {
>   struct task_struct *tsk;
>   unsigned long *stack;
> - struct vm_struct *stack_vm_area;
> + struct vm_struct *stack_vm_area __maybe_unused;
>   int err;
>  
>   if (node == NUMA_NO_NODE)
> 
> 
> 

-- 
Michal Hocko
SUSE Labs

[PATCH -next] mm: Mark 'stack_vm_area' with __maybe_unused

2018-12-27 Thread YueHaibing 
Fixes gcc '-Wunused-but-set-variable' warning when
CONFIG_VMAP_STACK is not set:

kernel/fork.c: In function 'dup_task_struct':
kernel/fork.c:843:20: warning:
 variable 'stack_vm_area' set but not used [-Wunused-but-set-variable]

Signed-off-by: YueHaibing 
---
 kernel/fork.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/fork.c b/kernel/fork.c
index e2a5156..b38c392 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -840,7 +840,7 @@ static struct task_struct *dup_task_struct(struct 
task_struct *orig, int node)
 {
struct task_struct *tsk;
unsigned long *stack;
-   struct vm_struct *stack_vm_area;
+   struct vm_struct *stack_vm_area __maybe_unused;
int err;
 
if (node == NUMA_NO_NODE)