[PATCH] mm/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER

[PATCH] mm/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER

[Ralph Campbell]

On x86_64, when CONFIG_MMU_NOTIFIER is not set/enabled, there is a
compiler error:

../mm/migrate.c: In function 'migrate_vma_collect':
../mm/migrate.c:2481:7: error: 'struct mmu_notifier_range' has no member
named 'migrate_pgmap_owner'
  range.migrate_pgmap_owner = migrate->pgmap_owner;
       ^

Fixes: 998427b3ad2c ("mm/notifier: add migration invalidation type")
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
---

This is based on the latest linux and is for Andrew Morton's mm tree.
MMU_NOTIFIER is selected automatically by a number of other config
options so I missed this in my own testing. Thanks to Randy Dunlap for
finding it.

 include/linux/mmu_notifier.h | 13 +++++++++++++
 mm/migrate.c                 |  6 +++---
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
index c6f0708195cd..b8200782dede 100644
--- a/include/linux/mmu_notifier.h
+++ b/include/linux/mmu_notifier.h
@@ -521,6 +521,16 @@ static inline void mmu_notifier_range_init(struct mmu_notifier_range *range,
 	range->flags = flags;
 }
 
+static inline void mmu_notifier_range_init_migrate(
+			struct mmu_notifier_range *range, unsigned int flags,
+			struct vm_area_struct *vma, struct mm_struct *mm,
+			unsigned long start, unsigned long end, void *pgmap)
+{
+	mmu_notifier_range_init(range, MMU_NOTIFY_MIGRATE, flags, vma, mm,
+				start, end);
+	range->migrate_pgmap_owner = pgmap;
+}
+
 #define ptep_clear_flush_young_notify(__vma, __address, __ptep)		\
 ({									\
 	int __young;							\
@@ -645,6 +655,9 @@ static inline void _mmu_notifier_range_init(struct mmu_notifier_range *range,
 
 #define mmu_notifier_range_init(range,event,flags,vma,mm,start,end)  \
 	_mmu_notifier_range_init(range, start, end)
+#define mmu_notifier_range_init_migrate(range, flags, vma, mm, start, end, \
+					pgmap) \
+	_mmu_notifier_range_init(range, start, end)
 
 static inline bool
 mmu_notifier_range_blockable(const struct mmu_notifier_range *range)
diff --git a/mm/migrate.c b/mm/migrate.c
index 4fcc465736ff..d179657f8685 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2386,9 +2386,9 @@ static void migrate_vma_collect(struct migrate_vma *migrate)
 	 * that the registered device driver can skip invalidating device
 	 * private page mappings that won't be migrated.
 	 */
-	mmu_notifier_range_init(&range, MMU_NOTIFY_MIGRATE, 0, migrate->vma,
-			migrate->vma->vm_mm, migrate->start, migrate->end);
-	range.migrate_pgmap_owner = migrate->pgmap_owner;
+	mmu_notifier_range_init_migrate(&range, 0, migrate->vma,
+		migrate->vma->vm_mm, migrate->start, migrate->end,
+		migrate->pgmap_owner);
 	mmu_notifier_invalidate_range_start(&range);
 
 	walk_page_range(migrate->vma->vm_mm, migrate->start, migrate->end,
-- 
2.20.1

Re: [PATCH] mm/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER

[Randy Dunlap]

On 8/6/20 12:33 PM, Ralph Campbell wrote:
> On x86_64, when CONFIG_MMU_NOTIFIER is not set/enabled, there is a
> compiler error:
> 
> ../mm/migrate.c: In function 'migrate_vma_collect':
> ../mm/migrate.c:2481:7: error: 'struct mmu_notifier_range' has no member
> named 'migrate_pgmap_owner'
>   range.migrate_pgmap_owner = migrate->pgmap_owner;
>        ^
> 
> Fixes: 998427b3ad2c ("mm/notifier: add migration invalidation type")
> Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
> Reported-by: Randy Dunlap <rdunlap@infradead.org>

Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested

Thanks.


> ---
> 
> This is based on the latest linux and is for Andrew Morton's mm tree.
> MMU_NOTIFIER is selected automatically by a number of other config
> options so I missed this in my own testing. Thanks to Randy Dunlap for
> finding it.
> 
>  include/linux/mmu_notifier.h | 13 +++++++++++++
>  mm/migrate.c                 |  6 +++---
>  2 files changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/include/linux/mmu_notifier.h b/include/linux/mmu_notifier.h
> index c6f0708195cd..b8200782dede 100644
> --- a/include/linux/mmu_notifier.h
> +++ b/include/linux/mmu_notifier.h
> @@ -521,6 +521,16 @@ static inline void mmu_notifier_range_init(struct mmu_notifier_range *range,
>  	range->flags = flags;
>  }
>  
> +static inline void mmu_notifier_range_init_migrate(
> +			struct mmu_notifier_range *range, unsigned int flags,
> +			struct vm_area_struct *vma, struct mm_struct *mm,
> +			unsigned long start, unsigned long end, void *pgmap)
> +{
> +	mmu_notifier_range_init(range, MMU_NOTIFY_MIGRATE, flags, vma, mm,
> +				start, end);
> +	range->migrate_pgmap_owner = pgmap;
> +}
> +
>  #define ptep_clear_flush_young_notify(__vma, __address, __ptep)		\
>  ({									\
>  	int __young;							\
> @@ -645,6 +655,9 @@ static inline void _mmu_notifier_range_init(struct mmu_notifier_range *range,
>  
>  #define mmu_notifier_range_init(range,event,flags,vma,mm,start,end)  \
>  	_mmu_notifier_range_init(range, start, end)
> +#define mmu_notifier_range_init_migrate(range, flags, vma, mm, start, end, \
> +					pgmap) \
> +	_mmu_notifier_range_init(range, start, end)
>  
>  static inline bool
>  mmu_notifier_range_blockable(const struct mmu_notifier_range *range)
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 4fcc465736ff..d179657f8685 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -2386,9 +2386,9 @@ static void migrate_vma_collect(struct migrate_vma *migrate)
>  	 * that the registered device driver can skip invalidating device
>  	 * private page mappings that won't be migrated.
>  	 */
> -	mmu_notifier_range_init(&range, MMU_NOTIFY_MIGRATE, 0, migrate->vma,
> -			migrate->vma->vm_mm, migrate->start, migrate->end);
> -	range.migrate_pgmap_owner = migrate->pgmap_owner;
> +	mmu_notifier_range_init_migrate(&range, 0, migrate->vma,
> +		migrate->vma->vm_mm, migrate->start, migrate->end,
> +		migrate->pgmap_owner);
>  	mmu_notifier_invalidate_range_start(&range);
>  
>  	walk_page_range(migrate->vma->vm_mm, migrate->start, migrate->end,
> 


-- 
~Randy

Re: [PATCH] mm/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER

[Jason Gunthorpe]

On Thu, Aug 06, 2020 at 04:39:58PM -0700, Randy Dunlap wrote:
> On 8/6/20 12:33 PM, Ralph Campbell wrote:
> > On x86_64, when CONFIG_MMU_NOTIFIER is not set/enabled, there is a
> > compiler error:
> > 
> > ../mm/migrate.c: In function 'migrate_vma_collect':
> > ../mm/migrate.c:2481:7: error: 'struct mmu_notifier_range' has no member
> > named 'migrate_pgmap_owner'
> >   range.migrate_pgmap_owner = migrate->pgmap_owner;
> >        ^
> > 
> > Fixes: 998427b3ad2c ("mm/notifier: add migration invalidation type")
> > Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
> > Reported-by: Randy Dunlap <rdunlap@infradead.org>
> 
> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

I thought it spent enough time in linux-next and for 0-day to catch
things like this, but I guess I was wrong.

Linus has already merged the hmm pull request.

Andrew Morton: Can you pick this fix up to forward to Linus?

Thanks,
Jason