[PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Zhengwang Ruan]

GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
'buffer' is used as returned value, and 'buffer_size' is initialized using
uninitialized_var to clear warning.

Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>
---
v2: added a subsystem prefix to the subject
---
 drivers/staging/android/binder.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index 4350425..6caebeb 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -716,8 +716,8 @@ static struct binder_buffer *binder_alloc_buf(struct binder_proc *proc,
 					      size_t offsets_size, int is_async)
 {
 	struct rb_node *n = proc->free_buffers.rb_node;
-	struct binder_buffer *buffer;
-	size_t buffer_size;
+	struct binder_buffer *buffer = NULL;
+	size_t uninitialized_var(buffer_size);
 	struct rb_node *best_fit = NULL;
 	void *has_page_addr;
 	void *end_page_addr;
-- 
1.6.0.4

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Dan Carpenter]

[-- Attachment #1: Type: text/plain, Size: 369 bytes --]

On Mon, Feb 27, 2012 at 06:17:51PM +0800, Zhengwang Ruan wrote:
> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
> 'buffer' is used as returned value, and 'buffer_size' is initialized using
> uninitialized_var to clear warning.
> 
> Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>

Looks good.

regards,
dan carpenter


[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

[PATCH 1/2 v2] Staging:android: Change type for binder_debug_no_lock switch to bool

[Zhengwang Ruan]

GCC warns that module_param_named() indirectly returns a bool type value
which is different from 'int' type binder_debug_no_lock declared. Change
it to bool because it is a internal switch for debugging.

Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>
---
v2: added a subsystem prefix to the subject
---
 drivers/staging/android/binder.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index f0b7e66..4350425 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -103,7 +103,7 @@ static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
 	BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
 module_param_named(debug_mask, binder_debug_mask, uint, S_IWUSR | S_IRUGO);
 
-static int binder_debug_no_lock;
+static bool binder_debug_no_lock;
 module_param_named(proc_no_lock, binder_debug_no_lock, bool, S_IWUSR | S_IRUGO);
 
 static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
-- 
1.6.0.4

[PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Zhengwang Ruan]

GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
'buffer' is used as returned value, and 'buffer_size' is initialized using
uninitialized_var to clear warning.

Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>
---
v2: added a subsystem prefix to the subject
---
 drivers/staging/android/binder.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index 4350425..6caebeb 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -716,8 +716,8 @@ static struct binder_buffer *binder_alloc_buf(struct binder_proc *proc,
 					      size_t offsets_size, int is_async)
 {
 	struct rb_node *n = proc->free_buffers.rb_node;
-	struct binder_buffer *buffer;
-	size_t buffer_size;
+	struct binder_buffer *buffer = NULL;
+	size_t uninitialized_var(buffer_size);
 	struct rb_node *best_fit = NULL;
 	void *has_page_addr;
 	void *end_page_addr;
-- 
1.6.0.4

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Arve Hjønnevåg]

On Tue, Mar 6, 2012 at 6:36 PM, Zhengwang Ruan <ruan.zhengwang@gmail.com> wrote:
> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
> 'buffer' is used as returned value, and 'buffer_size' is initialized using
> uninitialized_var to clear warning.

Why do you clear the warning on buffer_size with uninitialized_var()
but not on buffer? Neither variable is used before being initialized.

-- 
Arve Hjønnevåg
--
To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Zhengwang Ruan]

-------- Original Message --------
From: Arve Hjønnevåg
Sent: 2012年03月06日 星期二 20时01分58秒
To: Zhengwang Ruan
Subject: Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and 
buffer_size
before used
> On Tue, Mar 6, 2012 at 6:36 PM, Zhengwang Ruan<ruan.zhengwang@gmail.com>  wrote:
>> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
>> 'buffer' is used as returned value, and 'buffer_size' is initialized using
>> uninitialized_var to clear warning.
> Why do you clear the warning on buffer_size with uninitialized_var()
> but not on buffer?

struct binder_buffer *buffer;
size_t buffer_size;
struct rb_node *best_fit = NULL;

I see 'best_fit' is initialized by being directly assigned a NULL 
pointer, I think it should be better to initialize pointer in this way.

> Neither variable is used before being initialized.
>
I got the following compiling warning against buffer ans buffer_size:

drivers/staging/android/binder.c:719:24: warning: ‘buffer’ may be used 
uninitialized in this function
drivers/staging/android/binder.c:720:9: warning: ‘buffer_size’ may be 
used uninitialized in this function

Thanks,
-Zhengwang

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Greg KH]

On Wed, Mar 07, 2012 at 10:36:58AM +0800, Zhengwang Ruan wrote:
> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
> 'buffer' is used as returned value, and 'buffer_size' is initialized using
> uninitialized_var to clear warning.

Doesn't say that for me at all, what version of gcc are you using?  I'm
using 4.6.2 here, and if you are using an older version, then please
upgrade to one smarter than the one you are using.

As you are trying to paper over gcc issues, I can't take this patch,
sorry.

greg k-h

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Zhengwang Ruan]

-------- Original Message --------
From: Greg KH
Sent: 2012年03月06日 星期二 21时46分16秒
To: Zhengwang Ruan
Subject: Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and
buffer_size before used
> On Wed, Mar 07, 2012 at 10:36:58AM +0800, Zhengwang Ruan wrote:
>> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
>> 'buffer' is used as returned value, and 'buffer_size' is initialized using
>> uninitialized_var to clear warning.
> Doesn't say that for me at all, what version of gcc are you using?  I'm
> using 4.6.2 here, and if you are using an older version, then please
> upgrade to one smarter than the one you are using.
>
> As you are trying to paper over gcc issues, I can't take this patch,
> sorry.
>

Ok, I will make another try after updating GCC to 4.6. Thank you for 
your effort!

Thanks,
-Zhengwang

> greg k-h
>

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Dan Carpenter]

[-- Attachment #1: Type: text/plain, Size: 406 bytes --]

On Wed, Mar 07, 2012 at 10:36:58AM +0800, Zhengwang Ruan wrote:
> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
> 'buffer' is used as returned value, and 'buffer_size' is initialized using
> uninitialized_var to clear warning.
> 
> Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>

These are resends.  Why are you resending these?

regards,
dan carpenter


[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Zhengwang Ruan]

-------- Original Message --------
From: Dan Carpenter
Sent: 2012年03月07日 星期三 09时00分17秒
To: Zhengwang Ruan
Subject: Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and
buffer_size before used
> On Wed, Mar 07, 2012 at 10:36:58AM +0800, Zhengwang Ruan wrote:
>> GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
>> 'buffer' is used as returned value, and 'buffer_size' is initialized using
>> uninitialized_var to clear warning.
>>
>> Signed-off-by: Zhengwang Ruan<ruan.zhengwang@gmail.com>
> These are resends.  Why are you resending these?

I found I did not send this patch to everyone listed by 
get_maintainer.pl, and I didn't get any response, so I made another try 
today. :-)

Thanks,
-Zhengwang

> regards,
> dan carpenter
>

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Dan Carpenter]

[-- Attachment #1: Type: text/plain, Size: 525 bytes --]

On Wed, Mar 07, 2012 at 02:01:02PM +0800, Zhengwang Ruan wrote:
> I found I did not send this patch to everyone listed by
> get_maintainer.pl, and I didn't get any response, so I made another
> try today. :-)
> 

Please just be patient.

It is a messy thing because now there are comments on this resend
which will never be read until after the original patch submission
is applied.  If people want their comments read, they should go to
the original patch and write something there.

regards,
dan carpenter


[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[Zhengwang Ruan]

-------- Original Message --------
From: Dan Carpenter
Sent: 2012年03月07日 星期三 09时20分33秒
To: Zhengwang Ruan
Subject: Re: [PATCH 2/2 v2] Staging:android: Initialise buffer and
buffer_size before used
> On Wed, Mar 07, 2012 at 02:01:02PM +0800, Zhengwang Ruan wrote:
>> I found I did not send this patch to everyone listed by
>> get_maintainer.pl, and I didn't get any response, so I made another
>> try today. :-)
>>
> Please just be patient.
>
> It is a messy thing because now there are comments on this resend
> which will never be read until after the original patch submission
> is applied.  If people want their comments read, they should go to
> the original patch and write something there.

Yes, got it! I will avoid making similar mistakes again in the future. 
Thank you for your clarification, it is quite helpful!

Thanks,
-Zhengwang
> regards,
> dan carpenter
>

[PATCH 1/2 v2] Staging:android: Change type for binder_debug_no_lock switch to bool

[ruan.zhengwang]

From: Zhengwang Ruan <ruan.zhengwang@gmail.com>

GCC warns that module_param_named() indirectly returns a bool type value
which is different from 'int' type binder_debug_no_lock declared. Change
it to bool because it is a internal switch for debugging.

Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>
---
v2: added a subsystem prefix to the subject
---
 drivers/staging/android/binder.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index f0b7e66..4350425 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -103,7 +103,7 @@ static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
 	BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
 module_param_named(debug_mask, binder_debug_mask, uint, S_IWUSR | S_IRUGO);
 
-static int binder_debug_no_lock;
+static bool binder_debug_no_lock;
 module_param_named(proc_no_lock, binder_debug_no_lock, bool, S_IWUSR | S_IRUGO);
 
 static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
-- 
1.6.0.4

[PATCH 2/2 v2] Staging:android: Initialise buffer and buffer_size before used

[ruan.zhengwang]

From: Zhengwang Ruan <ruan.zhengwang@gmail.com>

GCC warns 'buffer' and 'buffer_size' are used with being uninitialized, and
'buffer' is used as returned value, and 'buffer_size' is initialized using
uninitialized_var to clear warning.

Signed-off-by: Zhengwang Ruan <ruan.zhengwang@gmail.com>
---
v2: added a subsystem prefix to the subject
---
 drivers/staging/android/binder.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index 4350425..6caebeb 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -716,8 +716,8 @@ static struct binder_buffer *binder_alloc_buf(struct binder_proc *proc,
 					      size_t offsets_size, int is_async)
 {
 	struct rb_node *n = proc->free_buffers.rb_node;
-	struct binder_buffer *buffer;
-	size_t buffer_size;
+	struct binder_buffer *buffer = NULL;
+	size_t uninitialized_var(buffer_size);
 	struct rb_node *best_fit = NULL;
 	void *has_page_addr;
 	void *end_page_addr;
-- 
1.6.0.4