Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-12 Thread Zhang Yanfei
On 06/12/2014 02:02 PM, Joonsoo Kim wrote:
 On Thu, Jun 12, 2014 at 02:25:43PM +0900, Minchan Kim wrote:
 On Thu, Jun 12, 2014 at 12:21:39PM +0900, Joonsoo Kim wrote:
 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

 Then, -stable stuff?
 
 I don't think so. This is just possible leak candidate, so we don't
 need to push this to stable tree.
 


 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.

 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
 base_pfn = pfn;
 for (j = pageblock_nr_pages; j; --j, pfn++) {
 WARN_ON_ONCE(!pfn_valid(pfn));
 +   /*
 +* alloc_contig_range requires the pfn range
 +* specified to be in the same zone. Make this
 +* simple by forcing the entire CMA resv range
 +* to be in the same zone.
 +*/
 if (page_zone(pfn_to_page(pfn)) != zone)
 -   return -EINVAL;
 +   goto err;

 At a first glance, I thought it would be better to handle such error
 before activating.
 So when I see the registration code(ie, dma_contiguous_revere_area),
 I realized it is impossible because we didn't set up zone yet. :(

 If so, when we detect to fail here, it would be better to report more
 meaningful error message like what was successful zone and what is
 new zone and failed pfn number?
 
 What I want to do in early phase of this patchset is to make cma code
 on DMA APIs similar to ppc kvm's cma code. ppc kvm's cma code already
 has this error handling logic, so I make this patch.
 
 If we think that we need more things, we can do that on general cma code
 after merging this patchset.
 

Yeah, I also like the idea. After all, this patchset aims to a general CMA
management, we could improve more after this patchset. So

Acked-by: Zhang Yanfei zhangyan...@cn.fujitsu.com

-- 
Thanks.
Zhang Yanfei
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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-12 Thread Michal Nazarewicz
On Thu, Jun 12 2014, Joonsoo Kim iamjoonsoo@lge.com wrote:
 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.

 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

Reviewed-by: Michal Nazarewicz min...@mina86.com

 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
   base_pfn = pfn;
   for (j = pageblock_nr_pages; j; --j, pfn++) {
   WARN_ON_ONCE(!pfn_valid(pfn));
 + /*
 +  * alloc_contig_range requires the pfn range
 +  * specified to be in the same zone. Make this
 +  * simple by forcing the entire CMA resv range
 +  * to be in the same zone.
 +  */
   if (page_zone(pfn_to_page(pfn)) != zone)
 - return -EINVAL;
 + goto err;
   }
   init_cma_reserved_pageblock(pfn_to_page(base_pfn));
   } while (--i);
  
   mutex_init(cma-lock);
   return 0;
 +
 +err:
 + kfree(cma-bitmap);
 + return -EINVAL;
  }

-- 
Best regards, _ _
.o. | Liege of Serenely Enlightened Majesty of  o' \,=./ `o
..o | Computer Science,  Michał “mina86” Nazarewicz(o o)
ooo +--m...@google.com--xmpp:min...@jabber.org--ooO--(_)--Ooo--
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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-12 Thread Zhang Yanfei
On 06/12/2014 02:02 PM, Joonsoo Kim wrote:
 On Thu, Jun 12, 2014 at 02:25:43PM +0900, Minchan Kim wrote:
 On Thu, Jun 12, 2014 at 12:21:39PM +0900, Joonsoo Kim wrote:
 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

 Then, -stable stuff?
 
 I don't think so. This is just possible leak candidate, so we don't
 need to push this to stable tree.
 


 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.

 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
 base_pfn = pfn;
 for (j = pageblock_nr_pages; j; --j, pfn++) {
 WARN_ON_ONCE(!pfn_valid(pfn));
 +   /*
 +* alloc_contig_range requires the pfn range
 +* specified to be in the same zone. Make this
 +* simple by forcing the entire CMA resv range
 +* to be in the same zone.
 +*/
 if (page_zone(pfn_to_page(pfn)) != zone)
 -   return -EINVAL;
 +   goto err;

 At a first glance, I thought it would be better to handle such error
 before activating.
 So when I see the registration code(ie, dma_contiguous_revere_area),
 I realized it is impossible because we didn't set up zone yet. :(

 If so, when we detect to fail here, it would be better to report more
 meaningful error message like what was successful zone and what is
 new zone and failed pfn number?
 
 What I want to do in early phase of this patchset is to make cma code
 on DMA APIs similar to ppc kvm's cma code. ppc kvm's cma code already
 has this error handling logic, so I make this patch.
 
 If we think that we need more things, we can do that on general cma code
 after merging this patchset.
 

Yeah, I also like the idea. After all, this patchset aims to a general CMA
management, we could improve more after this patchset. So

Acked-by: Zhang Yanfei zhangyan...@cn.fujitsu.com

-- 
Thanks.
Zhang Yanfei
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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-12 Thread Michal Nazarewicz
On Thu, Jun 12 2014, Joonsoo Kim iamjoonsoo@lge.com wrote:
 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.

 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

Reviewed-by: Michal Nazarewicz min...@mina86.com

 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
   base_pfn = pfn;
   for (j = pageblock_nr_pages; j; --j, pfn++) {
   WARN_ON_ONCE(!pfn_valid(pfn));
 + /*
 +  * alloc_contig_range requires the pfn range
 +  * specified to be in the same zone. Make this
 +  * simple by forcing the entire CMA resv range
 +  * to be in the same zone.
 +  */
   if (page_zone(pfn_to_page(pfn)) != zone)
 - return -EINVAL;
 + goto err;
   }
   init_cma_reserved_pageblock(pfn_to_page(base_pfn));
   } while (--i);
  
   mutex_init(cma-lock);
   return 0;
 +
 +err:
 + kfree(cma-bitmap);
 + return -EINVAL;
  }

-- 
Best regards, _ _
.o. | Liege of Serenely Enlightened Majesty of  o' \,=./ `o
..o | Computer Science,  Michał “mina86” Nazarewicz(o o)
ooo +--m...@google.com--xmpp:min...@jabber.org--ooO--(_)--Ooo--
--
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[PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Joonsoo Kim
We should free memory for bitmap when we find zone mis-match,
otherwise this memory will leak.

Additionally, I copy code comment from ppc kvm's cma code to notify
why we need to check zone mis-match.

Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index bd0bb81..fb0cdce 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
base_pfn = pfn;
for (j = pageblock_nr_pages; j; --j, pfn++) {
WARN_ON_ONCE(!pfn_valid(pfn));
+   /*
+* alloc_contig_range requires the pfn range
+* specified to be in the same zone. Make this
+* simple by forcing the entire CMA resv range
+* to be in the same zone.
+*/
if (page_zone(pfn_to_page(pfn)) != zone)
-   return -EINVAL;
+   goto err;
}
init_cma_reserved_pageblock(pfn_to_page(base_pfn));
} while (--i);
 
mutex_init(cma-lock);
return 0;
+
+err:
+   kfree(cma-bitmap);
+   return -EINVAL;
 }
 
 static struct cma cma_areas[MAX_CMA_AREAS];
-- 
1.7.9.5

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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Aneesh Kumar K.V
Joonsoo Kim iamjoonsoo@lge.com writes:

 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.

 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

Reviewed-by: Aneesh Kumar K.V aneesh.ku...@linux.vnet.ibm.com


 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
   base_pfn = pfn;
   for (j = pageblock_nr_pages; j; --j, pfn++) {
   WARN_ON_ONCE(!pfn_valid(pfn));
 + /*
 +  * alloc_contig_range requires the pfn range
 +  * specified to be in the same zone. Make this
 +  * simple by forcing the entire CMA resv range
 +  * to be in the same zone.
 +  */
   if (page_zone(pfn_to_page(pfn)) != zone)
 - return -EINVAL;
 + goto err;
   }
   init_cma_reserved_pageblock(pfn_to_page(base_pfn));
   } while (--i);

   mutex_init(cma-lock);
   return 0;
 +
 +err:
 + kfree(cma-bitmap);
 + return -EINVAL;
  }

  static struct cma cma_areas[MAX_CMA_AREAS];
 -- 
 1.7.9.5

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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Minchan Kim
On Thu, Jun 12, 2014 at 12:21:39PM +0900, Joonsoo Kim wrote:
 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

Then, -stable stuff?

 
 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.
 
 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
 
 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
   base_pfn = pfn;
   for (j = pageblock_nr_pages; j; --j, pfn++) {
   WARN_ON_ONCE(!pfn_valid(pfn));
 + /*
 +  * alloc_contig_range requires the pfn range
 +  * specified to be in the same zone. Make this
 +  * simple by forcing the entire CMA resv range
 +  * to be in the same zone.
 +  */
   if (page_zone(pfn_to_page(pfn)) != zone)
 - return -EINVAL;
 + goto err;

At a first glance, I thought it would be better to handle such error
before activating.
So when I see the registration code(ie, dma_contiguous_revere_area),
I realized it is impossible because we didn't set up zone yet. :(

If so, when we detect to fail here, it would be better to report more
meaningful error message like what was successful zone and what is
new zone and failed pfn number?

   }
   init_cma_reserved_pageblock(pfn_to_page(base_pfn));
   } while (--i);
  
   mutex_init(cma-lock);
   return 0;
 +
 +err:
 + kfree(cma-bitmap);
 + return -EINVAL;
  }
  
  static struct cma cma_areas[MAX_CMA_AREAS];
 -- 
 1.7.9.5

-- 
Kind regards,
Minchan Kim
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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Joonsoo Kim
On Thu, Jun 12, 2014 at 02:25:43PM +0900, Minchan Kim wrote:
 On Thu, Jun 12, 2014 at 12:21:39PM +0900, Joonsoo Kim wrote:
  We should free memory for bitmap when we find zone mis-match,
  otherwise this memory will leak.
 
 Then, -stable stuff?

I don't think so. This is just possible leak candidate, so we don't
need to push this to stable tree.

 
  
  Additionally, I copy code comment from ppc kvm's cma code to notify
  why we need to check zone mis-match.
  
  Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
  
  diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
  index bd0bb81..fb0cdce 100644
  --- a/drivers/base/dma-contiguous.c
  +++ b/drivers/base/dma-contiguous.c
  @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
  base_pfn = pfn;
  for (j = pageblock_nr_pages; j; --j, pfn++) {
  WARN_ON_ONCE(!pfn_valid(pfn));
  +   /*
  +* alloc_contig_range requires the pfn range
  +* specified to be in the same zone. Make this
  +* simple by forcing the entire CMA resv range
  +* to be in the same zone.
  +*/
  if (page_zone(pfn_to_page(pfn)) != zone)
  -   return -EINVAL;
  +   goto err;
 
 At a first glance, I thought it would be better to handle such error
 before activating.
 So when I see the registration code(ie, dma_contiguous_revere_area),
 I realized it is impossible because we didn't set up zone yet. :(
 
 If so, when we detect to fail here, it would be better to report more
 meaningful error message like what was successful zone and what is
 new zone and failed pfn number?

What I want to do in early phase of this patchset is to make cma code
on DMA APIs similar to ppc kvm's cma code. ppc kvm's cma code already
has this error handling logic, so I make this patch.

If we think that we need more things, we can do that on general cma code
after merging this patchset.

Thanks.

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[PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Joonsoo Kim
We should free memory for bitmap when we find zone mis-match,
otherwise this memory will leak.

Additionally, I copy code comment from ppc kvm's cma code to notify
why we need to check zone mis-match.

Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index bd0bb81..fb0cdce 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
base_pfn = pfn;
for (j = pageblock_nr_pages; j; --j, pfn++) {
WARN_ON_ONCE(!pfn_valid(pfn));
+   /*
+* alloc_contig_range requires the pfn range
+* specified to be in the same zone. Make this
+* simple by forcing the entire CMA resv range
+* to be in the same zone.
+*/
if (page_zone(pfn_to_page(pfn)) != zone)
-   return -EINVAL;
+   goto err;
}
init_cma_reserved_pageblock(pfn_to_page(base_pfn));
} while (--i);
 
mutex_init(cma-lock);
return 0;
+
+err:
+   kfree(cma-bitmap);
+   return -EINVAL;
 }
 
 static struct cma cma_areas[MAX_CMA_AREAS];
-- 
1.7.9.5

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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Aneesh Kumar K.V
Joonsoo Kim iamjoonsoo@lge.com writes:

 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.

 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com

Reviewed-by: Aneesh Kumar K.V aneesh.ku...@linux.vnet.ibm.com


 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
   base_pfn = pfn;
   for (j = pageblock_nr_pages; j; --j, pfn++) {
   WARN_ON_ONCE(!pfn_valid(pfn));
 + /*
 +  * alloc_contig_range requires the pfn range
 +  * specified to be in the same zone. Make this
 +  * simple by forcing the entire CMA resv range
 +  * to be in the same zone.
 +  */
   if (page_zone(pfn_to_page(pfn)) != zone)
 - return -EINVAL;
 + goto err;
   }
   init_cma_reserved_pageblock(pfn_to_page(base_pfn));
   } while (--i);

   mutex_init(cma-lock);
   return 0;
 +
 +err:
 + kfree(cma-bitmap);
 + return -EINVAL;
  }

  static struct cma cma_areas[MAX_CMA_AREAS];
 -- 
 1.7.9.5

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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Minchan Kim
On Thu, Jun 12, 2014 at 12:21:39PM +0900, Joonsoo Kim wrote:
 We should free memory for bitmap when we find zone mis-match,
 otherwise this memory will leak.

Then, -stable stuff?

 
 Additionally, I copy code comment from ppc kvm's cma code to notify
 why we need to check zone mis-match.
 
 Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
 
 diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
 index bd0bb81..fb0cdce 100644
 --- a/drivers/base/dma-contiguous.c
 +++ b/drivers/base/dma-contiguous.c
 @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
   base_pfn = pfn;
   for (j = pageblock_nr_pages; j; --j, pfn++) {
   WARN_ON_ONCE(!pfn_valid(pfn));
 + /*
 +  * alloc_contig_range requires the pfn range
 +  * specified to be in the same zone. Make this
 +  * simple by forcing the entire CMA resv range
 +  * to be in the same zone.
 +  */
   if (page_zone(pfn_to_page(pfn)) != zone)
 - return -EINVAL;
 + goto err;

At a first glance, I thought it would be better to handle such error
before activating.
So when I see the registration code(ie, dma_contiguous_revere_area),
I realized it is impossible because we didn't set up zone yet. :(

If so, when we detect to fail here, it would be better to report more
meaningful error message like what was successful zone and what is
new zone and failed pfn number?

   }
   init_cma_reserved_pageblock(pfn_to_page(base_pfn));
   } while (--i);
  
   mutex_init(cma-lock);
   return 0;
 +
 +err:
 + kfree(cma-bitmap);
 + return -EINVAL;
  }
  
  static struct cma cma_areas[MAX_CMA_AREAS];
 -- 
 1.7.9.5

-- 
Kind regards,
Minchan Kim
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Re: [PATCH v2 02/10] DMA, CMA: fix possible memory leak

2014-06-11 Thread Joonsoo Kim
On Thu, Jun 12, 2014 at 02:25:43PM +0900, Minchan Kim wrote:
 On Thu, Jun 12, 2014 at 12:21:39PM +0900, Joonsoo Kim wrote:
  We should free memory for bitmap when we find zone mis-match,
  otherwise this memory will leak.
 
 Then, -stable stuff?

I don't think so. This is just possible leak candidate, so we don't
need to push this to stable tree.

 
  
  Additionally, I copy code comment from ppc kvm's cma code to notify
  why we need to check zone mis-match.
  
  Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com
  
  diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
  index bd0bb81..fb0cdce 100644
  --- a/drivers/base/dma-contiguous.c
  +++ b/drivers/base/dma-contiguous.c
  @@ -177,14 +177,24 @@ static int __init cma_activate_area(struct cma *cma)
  base_pfn = pfn;
  for (j = pageblock_nr_pages; j; --j, pfn++) {
  WARN_ON_ONCE(!pfn_valid(pfn));
  +   /*
  +* alloc_contig_range requires the pfn range
  +* specified to be in the same zone. Make this
  +* simple by forcing the entire CMA resv range
  +* to be in the same zone.
  +*/
  if (page_zone(pfn_to_page(pfn)) != zone)
  -   return -EINVAL;
  +   goto err;
 
 At a first glance, I thought it would be better to handle such error
 before activating.
 So when I see the registration code(ie, dma_contiguous_revere_area),
 I realized it is impossible because we didn't set up zone yet. :(
 
 If so, when we detect to fail here, it would be better to report more
 meaningful error message like what was successful zone and what is
 new zone and failed pfn number?

What I want to do in early phase of this patchset is to make cma code
on DMA APIs similar to ppc kvm's cma code. ppc kvm's cma code already
has this error handling logic, so I make this patch.

If we think that we need more things, we can do that on general cma code
after merging this patchset.

Thanks.

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