[PATCH 02/14] mm/hmm: fix header file if/else/endif maze v2

[jglisse]

From: Jérôme Glisse 

The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong. Because
of this after multiple include there was multiple definition of both
hmm_mm_init() and hmm_mm_destroy() leading to build failure if HMM
was enabled (CONFIG_HMM set).

Changed since v1:
  - Fix the maze when CONFIG_HMM is disabled not just when it is
enabled. This fix bot build failure.
  - Improved commit message.

Signed-off-by: Jérôme Glisse 
Acked-by: Balbir Singh 
Cc: sta...@vger.kernel.org
Cc: Andrew Morton 
Cc: Ralph Campbell 
Cc: John Hubbard 
Cc: Evgeny Baskakov 
---
 include/linux/hmm.h | 9 +
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 325017ad9311..36dd21fe5caf 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -498,23 +498,16 @@ struct hmm_device {
 struct hmm_device *hmm_device_new(void *drvdata);
 void hmm_device_put(struct hmm_device *hmm_device);
 #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
-#endif /* IS_ENABLED(CONFIG_HMM) */
 
 /* Below are for HMM internal use only! Not to be used by device driver! */
-#if IS_ENABLED(CONFIG_HMM_MIRROR)
 void hmm_mm_destroy(struct mm_struct *mm);
 
 static inline void hmm_mm_init(struct mm_struct *mm)
 {
mm->hmm = NULL;
 }
-#else /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-static inline void hmm_mm_destroy(struct mm_struct *mm) {}
-static inline void hmm_mm_init(struct mm_struct *mm) {}
-#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-
-
 #else /* IS_ENABLED(CONFIG_HMM) */
 static inline void hmm_mm_destroy(struct mm_struct *mm) {}
 static inline void hmm_mm_init(struct mm_struct *mm) {}
+#endif /* IS_ENABLED(CONFIG_HMM) */
 #endif /* LINUX_HMM_H */
-- 
2.14.3

[PATCH 02/14] mm/hmm: fix header file if/else/endif maze v2

[jglisse]

From: Jérôme Glisse 

The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong. Because
of this after multiple include there was multiple definition of both
hmm_mm_init() and hmm_mm_destroy() leading to build failure if HMM
was enabled (CONFIG_HMM set).

Changed since v1:
  - Fix the maze when CONFIG_HMM is disabled not just when it is
enabled. This fix bot build failure.
  - Improved commit message.

Signed-off-by: Jérôme Glisse 
Acked-by: Balbir Singh 
Cc: sta...@vger.kernel.org
Cc: Andrew Morton 
Cc: Ralph Campbell 
Cc: John Hubbard 
Cc: Evgeny Baskakov 
---
 include/linux/hmm.h | 9 +
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 325017ad9311..36dd21fe5caf 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -498,23 +498,16 @@ struct hmm_device {
 struct hmm_device *hmm_device_new(void *drvdata);
 void hmm_device_put(struct hmm_device *hmm_device);
 #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
-#endif /* IS_ENABLED(CONFIG_HMM) */
 
 /* Below are for HMM internal use only! Not to be used by device driver! */
-#if IS_ENABLED(CONFIG_HMM_MIRROR)
 void hmm_mm_destroy(struct mm_struct *mm);
 
 static inline void hmm_mm_init(struct mm_struct *mm)
 {
mm->hmm = NULL;
 }
-#else /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-static inline void hmm_mm_destroy(struct mm_struct *mm) {}
-static inline void hmm_mm_init(struct mm_struct *mm) {}
-#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
-
-
 #else /* IS_ENABLED(CONFIG_HMM) */
 static inline void hmm_mm_destroy(struct mm_struct *mm) {}
 static inline void hmm_mm_init(struct mm_struct *mm) {}
+#endif /* IS_ENABLED(CONFIG_HMM) */
 #endif /* LINUX_HMM_H */
-- 
2.14.3

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[John Hubbard]

On 03/16/2018 02:35 PM, Andrew Morton wrote:
> On Fri, 16 Mar 2018 17:18:02 -0400 Jerome Glisse  wrote:
> 
>> On Fri, Mar 16, 2018 at 02:09:59PM -0700, Andrew Morton wrote:
>>> On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:
>>>
 From: Jérôme Glisse 

 The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.
>>>
>>> "were wrong" is not a sufficient explanation of the problem, especially
>>> if we're requesting a -stable backport.  Please fully describe the
>>> effects of a bug when fixing it?
>>
>> Build issue (compilation failure) if you have multiple includes of
>> hmm.h through different headers is the most obvious issue. So it
>> will be very obvious with any big driver that include the file in
>> different headers.
> 
> That doesn't seem to warrant a -stable backport?  The developer of such
> a driver will simply fix the headers?

Right. For this patch, I would strongly request a -stable backport.  It's 
really going to cause problems if anyone tries to use -stable with HMM,
without this fix.

thanks,
-- 
John Hubbard
NVIDIA

> 
>> I can respin with that. Sorry again for not being more explanatory
>> it is always hard for me to figure what is not obvious to others.
> 
> I updated the changelog, no respin needed.
> 

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[John Hubbard]

On 03/16/2018 02:35 PM, Andrew Morton wrote:
> On Fri, 16 Mar 2018 17:18:02 -0400 Jerome Glisse  wrote:
> 
>> On Fri, Mar 16, 2018 at 02:09:59PM -0700, Andrew Morton wrote:
>>> On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:
>>>
 From: Jérôme Glisse 

 The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.
>>>
>>> "were wrong" is not a sufficient explanation of the problem, especially
>>> if we're requesting a -stable backport.  Please fully describe the
>>> effects of a bug when fixing it?
>>
>> Build issue (compilation failure) if you have multiple includes of
>> hmm.h through different headers is the most obvious issue. So it
>> will be very obvious with any big driver that include the file in
>> different headers.
> 
> That doesn't seem to warrant a -stable backport?  The developer of such
> a driver will simply fix the headers?

Right. For this patch, I would strongly request a -stable backport.  It's 
really going to cause problems if anyone tries to use -stable with HMM,
without this fix.

thanks,
-- 
John Hubbard
NVIDIA

> 
>> I can respin with that. Sorry again for not being more explanatory
>> it is always hard for me to figure what is not obvious to others.
> 
> I updated the changelog, no respin needed.
> 

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[Andrew Morton]

On Fri, 16 Mar 2018 17:18:02 -0400 Jerome Glisse  wrote:

> On Fri, Mar 16, 2018 at 02:09:59PM -0700, Andrew Morton wrote:
> > On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:
> > 
> > > From: Jérôme Glisse 
> > > 
> > > The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.
> > 
> > "were wrong" is not a sufficient explanation of the problem, especially
> > if we're requesting a -stable backport.  Please fully describe the
> > effects of a bug when fixing it?
> 
> Build issue (compilation failure) if you have multiple includes of
> hmm.h through different headers is the most obvious issue. So it
> will be very obvious with any big driver that include the file in
> different headers.

That doesn't seem to warrant a -stable backport?  The developer of such
a driver will simply fix the headers?

> I can respin with that. Sorry again for not being more explanatory
> it is always hard for me to figure what is not obvious to others.

I updated the changelog, no respin needed.

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[Andrew Morton]

On Fri, 16 Mar 2018 17:18:02 -0400 Jerome Glisse  wrote:

> On Fri, Mar 16, 2018 at 02:09:59PM -0700, Andrew Morton wrote:
> > On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:
> > 
> > > From: Jérôme Glisse 
> > > 
> > > The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.
> > 
> > "were wrong" is not a sufficient explanation of the problem, especially
> > if we're requesting a -stable backport.  Please fully describe the
> > effects of a bug when fixing it?
> 
> Build issue (compilation failure) if you have multiple includes of
> hmm.h through different headers is the most obvious issue. So it
> will be very obvious with any big driver that include the file in
> different headers.

That doesn't seem to warrant a -stable backport?  The developer of such
a driver will simply fix the headers?

> I can respin with that. Sorry again for not being more explanatory
> it is always hard for me to figure what is not obvious to others.

I updated the changelog, no respin needed.

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[Jerome Glisse]

On Fri, Mar 16, 2018 at 02:09:59PM -0700, Andrew Morton wrote:
> On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:
> 
> > From: Jérôme Glisse 
> > 
> > The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.
> 
> "were wrong" is not a sufficient explanation of the problem, especially
> if we're requesting a -stable backport.  Please fully describe the
> effects of a bug when fixing it?

Build issue (compilation failure) if you have multiple includes of
hmm.h through different headers is the most obvious issue. So it
will be very obvious with any big driver that include the file in
different headers.

I can respin with that. Sorry again for not being more explanatory
it is always hard for me to figure what is not obvious to others.

Cheers,
Jérôme

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[Jerome Glisse]

On Fri, Mar 16, 2018 at 02:09:59PM -0700, Andrew Morton wrote:
> On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:
> 
> > From: Jérôme Glisse 
> > 
> > The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.
> 
> "were wrong" is not a sufficient explanation of the problem, especially
> if we're requesting a -stable backport.  Please fully describe the
> effects of a bug when fixing it?

Build issue (compilation failure) if you have multiple includes of
hmm.h through different headers is the most obvious issue. So it
will be very obvious with any big driver that include the file in
different headers.

I can respin with that. Sorry again for not being more explanatory
it is always hard for me to figure what is not obvious to others.

Cheers,
Jérôme

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[Andrew Morton]

On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:

> From: Jérôme Glisse 
> 
> The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.

"were wrong" is not a sufficient explanation of the problem, especially
if we're requesting a -stable backport.  Please fully describe the
effects of a bug when fixing it?

Re: [PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[Andrew Morton]

On Fri, 16 Mar 2018 15:14:07 -0400 jgli...@redhat.com wrote:

> From: Jérôme Glisse 
> 
> The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.

"were wrong" is not a sufficient explanation of the problem, especially
if we're requesting a -stable backport.  Please fully describe the
effects of a bug when fixing it?

[PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[jglisse]

From: Jérôme Glisse 

The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.

Signed-off-by: Jérôme Glisse 
Acked-by: Balbir Singh 
Cc: sta...@vger.kernel.org
Cc: Andrew Morton 
Cc: Ralph Campbell 
Cc: John Hubbard 
Cc: Evgeny Baskakov 
---
 include/linux/hmm.h | 7 +++
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 325017ad9311..ef6044d08cc5 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -498,6 +498,9 @@ struct hmm_device {
 struct hmm_device *hmm_device_new(void *drvdata);
 void hmm_device_put(struct hmm_device *hmm_device);
 #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
+#else /* IS_ENABLED(CONFIG_HMM) */
+static inline void hmm_mm_destroy(struct mm_struct *mm) {}
+static inline void hmm_mm_init(struct mm_struct *mm) {}
 #endif /* IS_ENABLED(CONFIG_HMM) */
 
 /* Below are for HMM internal use only! Not to be used by device driver! */
@@ -513,8 +516,4 @@ static inline void hmm_mm_destroy(struct mm_struct *mm) {}
 static inline void hmm_mm_init(struct mm_struct *mm) {}
 #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
 
-
-#else /* IS_ENABLED(CONFIG_HMM) */
-static inline void hmm_mm_destroy(struct mm_struct *mm) {}
-static inline void hmm_mm_init(struct mm_struct *mm) {}
 #endif /* LINUX_HMM_H */
-- 
2.14.3

[PATCH 02/14] mm/hmm: fix header file if/else/endif maze

[jglisse]

From: Jérôme Glisse 

The #if/#else/#endif for IS_ENABLED(CONFIG_HMM) were wrong.

Signed-off-by: Jérôme Glisse 
Acked-by: Balbir Singh 
Cc: sta...@vger.kernel.org
Cc: Andrew Morton 
Cc: Ralph Campbell 
Cc: John Hubbard 
Cc: Evgeny Baskakov 
---
 include/linux/hmm.h | 7 +++
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 325017ad9311..ef6044d08cc5 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -498,6 +498,9 @@ struct hmm_device {
 struct hmm_device *hmm_device_new(void *drvdata);
 void hmm_device_put(struct hmm_device *hmm_device);
 #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */
+#else /* IS_ENABLED(CONFIG_HMM) */
+static inline void hmm_mm_destroy(struct mm_struct *mm) {}
+static inline void hmm_mm_init(struct mm_struct *mm) {}
 #endif /* IS_ENABLED(CONFIG_HMM) */
 
 /* Below are for HMM internal use only! Not to be used by device driver! */
@@ -513,8 +516,4 @@ static inline void hmm_mm_destroy(struct mm_struct *mm) {}
 static inline void hmm_mm_init(struct mm_struct *mm) {}
 #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */
 
-
-#else /* IS_ENABLED(CONFIG_HMM) */
-static inline void hmm_mm_destroy(struct mm_struct *mm) {}
-static inline void hmm_mm_init(struct mm_struct *mm) {}
 #endif /* LINUX_HMM_H */
-- 
2.14.3