[PATCH] mm: fix corner case in anon_vma endless growing prevention

[PATCH] mm: fix corner case in anon_vma endless growing prevention

[Konstantin Khlebnikov]

Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
("kernel BUG at mm/rmap.c:399!").

Anon_vma_clone() is usually called for a copy of source vma in destination
argument. If source vma has anon_vma it should be already in dst->anon_vma.
NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
In this case anon_vma_clone() finds anon_vma for reusing.

Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
anon_vma_clone() links vma to old anon_vma and updates degree counters but
vma_adjust() overrides vma->anon_vma right after that. As a result final
unlink_anon_vmas() decrements degree for wrong anon_vma.

This patch assigns ->anon_vma before calling anon_vma_clone().

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
Tested-by: Chris Clayton <chris2553@googlemail.com>
Tested-by: Oded Gabbay <oded.gabbay@amd.com>
Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
---
 mm/mmap.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 7b36aa7..12616c5 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -778,10 +778,12 @@ again:			remove_next = 1 + (end > next->vm_end);
 		if (exporter && exporter->anon_vma && !importer->anon_vma) {
 			int error;
 
+			importer->anon_vma = exporter->anon_vma;
 			error = anon_vma_clone(importer, exporter);
-			if (error)
+			if (error) {
+				importer->anon_vma = NULL;
 				return error;
-			importer->anon_vma = exporter->anon_vma;
+			}
 		}
 	}
 

[PATCH] mm: fix corner case in anon_vma endless growing prevention

[Konstantin Khlebnikov]

Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
("kernel BUG at mm/rmap.c:399!").

Anon_vma_clone() is usually called for a copy of source vma in destination
argument. If source vma has anon_vma it should be already in dst->anon_vma.
NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
In this case anon_vma_clone() finds anon_vma for reusing.

Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
anon_vma_clone() links vma to old anon_vma and updates degree counters but
vma_adjust() overrides vma->anon_vma right after that. As a result final
unlink_anon_vmas() decrements degree for wrong anon_vma.

This patch assigns ->anon_vma before calling anon_vma_clone().

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
Tested-by: Chris Clayton <chris2553@googlemail.com>
Tested-by: Oded Gabbay <oded.gabbay@amd.com>
Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
---
 mm/mmap.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/mmap.c b/mm/mmap.c
index 7b36aa7..12616c5 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -778,10 +778,12 @@ again:			remove_next = 1 + (end > next->vm_end);
 		if (exporter && exporter->anon_vma && !importer->anon_vma) {
 			int error;
 
+			importer->anon_vma = exporter->anon_vma;
 			error = anon_vma_clone(importer, exporter);
-			if (error)
+			if (error) {
+				importer->anon_vma = NULL;
 				return error;
-			importer->anon_vma = exporter->anon_vma;
+			}
 		}
 	}
 

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Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Rik van Riel]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 01/11/2015 08:54 AM, Konstantin Khlebnikov wrote:
> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas() 
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in
> destination argument. If source vma has anon_vma it should be
> already in dst->anon_vma. NULL in dst->anon_vma is used as a sign
> that it's called from anon_vma_fork(). In this case
> anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing
> logic: anon_vma_clone() links vma to old anon_vma and updates
> degree counters but vma_adjust() overrides vma->anon_vma right
> after that. As a result final unlink_anon_vmas() decrements degree
> for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Fixes:
> 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy") 
> Tested-by: Chris Clayton <chris2553@googlemail.com> Tested-by: Oded
> Gabbay <oded.gabbay@amd.com> Cc: Daniel Forrest
> <dan.forrest@ssec.wisc.edu> Cc: Michal Hocko <mhocko@suse.cz> Cc:
> Rik van Riel <riel@redhat.com>

Acked-by: Rik van Riel <riel@redhat.com>

- -- 
All rights reversed
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Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Rik van Riel]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 01/11/2015 08:54 AM, Konstantin Khlebnikov wrote:
> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas() 
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in
> destination argument. If source vma has anon_vma it should be
> already in dst->anon_vma. NULL in dst->anon_vma is used as a sign
> that it's called from anon_vma_fork(). In this case
> anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing
> logic: anon_vma_clone() links vma to old anon_vma and updates
> degree counters but vma_adjust() overrides vma->anon_vma right
> after that. As a result final unlink_anon_vmas() decrements degree
> for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Fixes:
> 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy") 
> Tested-by: Chris Clayton <chris2553@googlemail.com> Tested-by: Oded
> Gabbay <oded.gabbay@amd.com> Cc: Daniel Forrest
> <dan.forrest@ssec.wisc.edu> Cc: Michal Hocko <mhocko@suse.cz> Cc:
> Rik van Riel <riel@redhat.com>

Acked-by: Rik van Riel <riel@redhat.com>

- -- 
All rights reversed
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Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Vlastimil Babka]

On 01/11/2015 02:54 PM, Konstantin Khlebnikov wrote:
> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in destination
> argument. If source vma has anon_vma it should be already in dst->anon_vma.
> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
> In this case anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
> anon_vma_clone() links vma to old anon_vma and updates degree counters but
> vma_adjust() overrides vma->anon_vma right after that. As a result final
> unlink_anon_vmas() decrements degree for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
> Tested-by: Chris Clayton <chris2553@googlemail.com>
> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
> Cc: Michal Hocko <mhocko@suse.cz>
> Cc: Rik van Riel <riel@redhat.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

> ---
>  mm/mmap.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7b36aa7..12616c5 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -778,10 +778,12 @@ again:			remove_next = 1 + (end > next->vm_end);
>  		if (exporter && exporter->anon_vma && !importer->anon_vma) {
>  			int error;
>  
> +			importer->anon_vma = exporter->anon_vma;
>  			error = anon_vma_clone(importer, exporter);
> -			if (error)
> +			if (error) {
> +				importer->anon_vma = NULL;
>  				return error;
> -			importer->anon_vma = exporter->anon_vma;
> +			}
>  		}
>  	}
>  
> 
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org.  For more info on Linux MM,
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> 

Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Vlastimil Babka]

On 01/11/2015 02:54 PM, Konstantin Khlebnikov wrote:
> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in destination
> argument. If source vma has anon_vma it should be already in dst->anon_vma.
> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
> In this case anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
> anon_vma_clone() links vma to old anon_vma and updates degree counters but
> vma_adjust() overrides vma->anon_vma right after that. As a result final
> unlink_anon_vmas() decrements degree for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
> Tested-by: Chris Clayton <chris2553@googlemail.com>
> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
> Cc: Michal Hocko <mhocko@suse.cz>
> Cc: Rik van Riel <riel@redhat.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

> ---
>  mm/mmap.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7b36aa7..12616c5 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -778,10 +778,12 @@ again:			remove_next = 1 + (end > next->vm_end);
>  		if (exporter && exporter->anon_vma && !importer->anon_vma) {
>  			int error;
>  
> +			importer->anon_vma = exporter->anon_vma;
>  			error = anon_vma_clone(importer, exporter);
> -			if (error)
> +			if (error) {
> +				importer->anon_vma = NULL;
>  				return error;
> -			importer->anon_vma = exporter->anon_vma;
> +			}
>  		}
>  	}
>  
> 
> --
> To unsubscribe, send a message with 'unsubscribe linux-mm' in
> the body to majordomo@kvack.org.  For more info on Linux MM,
> see: http://www.linux-mm.org/ .
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Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Michal Hocko]

On Sun 11-01-15 16:54:06, Konstantin Khlebnikov wrote:
> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in destination
> argument. If source vma has anon_vma it should be already in dst->anon_vma.
> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
> In this case anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
> anon_vma_clone() links vma to old anon_vma and updates degree counters but
> vma_adjust() overrides vma->anon_vma right after that. As a result final
> unlink_anon_vmas() decrements degree for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
> Tested-by: Chris Clayton <chris2553@googlemail.com>
> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
> Cc: Michal Hocko <mhocko@suse.cz>
> Cc: Rik van Riel <riel@redhat.com>

Reviewed-by: Michal Hocko <mhocko@suse.cz>

> ---
>  mm/mmap.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7b36aa7..12616c5 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -778,10 +778,12 @@ again:			remove_next = 1 + (end > next->vm_end);
>  		if (exporter && exporter->anon_vma && !importer->anon_vma) {
>  			int error;
>  
> +			importer->anon_vma = exporter->anon_vma;
>  			error = anon_vma_clone(importer, exporter);
> -			if (error)
> +			if (error) {
> +				importer->anon_vma = NULL;
>  				return error;
> -			importer->anon_vma = exporter->anon_vma;
> +			}
>  		}
>  	}
>  
> 

-- 
Michal Hocko
SUSE Labs

Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Michal Hocko]

On Sun 11-01-15 16:54:06, Konstantin Khlebnikov wrote:
> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in destination
> argument. If source vma has anon_vma it should be already in dst->anon_vma.
> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
> In this case anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
> anon_vma_clone() links vma to old anon_vma and updates degree counters but
> vma_adjust() overrides vma->anon_vma right after that. As a result final
> unlink_anon_vmas() decrements degree for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
> Tested-by: Chris Clayton <chris2553@googlemail.com>
> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
> Cc: Michal Hocko <mhocko@suse.cz>
> Cc: Rik van Riel <riel@redhat.com>

Reviewed-by: Michal Hocko <mhocko@suse.cz>

> ---
>  mm/mmap.c |    6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 7b36aa7..12616c5 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -778,10 +778,12 @@ again:			remove_next = 1 + (end > next->vm_end);
>  		if (exporter && exporter->anon_vma && !importer->anon_vma) {
>  			int error;
>  
> +			importer->anon_vma = exporter->anon_vma;
>  			error = anon_vma_clone(importer, exporter);
> -			if (error)
> +			if (error) {
> +				importer->anon_vma = NULL;
>  				return error;
> -			importer->anon_vma = exporter->anon_vma;
> +			}
>  		}
>  	}
>  
> 

-- 
Michal Hocko
SUSE Labs

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Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Andrew Morton]

On Sun, 11 Jan 2015 16:54:06 +0300 Konstantin Khlebnikov <koct9i@gmail.com> wrote:

> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in destination
> argument. If source vma has anon_vma it should be already in dst->anon_vma.
> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
> In this case anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
> anon_vma_clone() links vma to old anon_vma and updates degree counters but
> vma_adjust() overrides vma->anon_vma right after that. As a result final
> unlink_anon_vmas() decrements degree for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")

I've asked Greg not to take 7a3ef208e662 into -stable because of this
problem.  So if you still think we should fix this in -stable, could
you please prepare an updated patch and send it to Greg?

> Tested-by: Chris Clayton <chris2553@googlemail.com>
> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
> Cc: Michal Hocko <mhocko@suse.cz>
> Cc: Rik van Riel <riel@redhat.com>

Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Andrew Morton]

On Sun, 11 Jan 2015 16:54:06 +0300 Konstantin Khlebnikov <koct9i@gmail.com> wrote:

> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
> ("kernel BUG at mm/rmap.c:399!").
> 
> Anon_vma_clone() is usually called for a copy of source vma in destination
> argument. If source vma has anon_vma it should be already in dst->anon_vma.
> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
> In this case anon_vma_clone() finds anon_vma for reusing.
> 
> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
> anon_vma_clone() links vma to old anon_vma and updates degree counters but
> vma_adjust() overrides vma->anon_vma right after that. As a result final
> unlink_anon_vmas() decrements degree for wrong anon_vma.
> 
> This patch assigns ->anon_vma before calling anon_vma_clone().
> 
> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")

I've asked Greg not to take 7a3ef208e662 into -stable because of this
problem.  So if you still think we should fix this in -stable, could
you please prepare an updated patch and send it to Greg?

> Tested-by: Chris Clayton <chris2553@googlemail.com>
> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
> Cc: Michal Hocko <mhocko@suse.cz>
> Cc: Rik van Riel <riel@redhat.com>

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Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Konstantin Khlebnikov]

On Mon, Jan 12, 2015 at 11:21 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Sun, 11 Jan 2015 16:54:06 +0300 Konstantin Khlebnikov <koct9i@gmail.com> wrote:
>
>> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
>> ("kernel BUG at mm/rmap.c:399!").
>>
>> Anon_vma_clone() is usually called for a copy of source vma in destination
>> argument. If source vma has anon_vma it should be already in dst->anon_vma.
>> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
>> In this case anon_vma_clone() finds anon_vma for reusing.
>>
>> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
>> anon_vma_clone() links vma to old anon_vma and updates degree counters but
>> vma_adjust() overrides vma->anon_vma right after that. As a result final
>> unlink_anon_vmas() decrements degree for wrong anon_vma.
>>
>> This patch assigns ->anon_vma before calling anon_vma_clone().
>>
>> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
>> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
>
> I've asked Greg not to take 7a3ef208e662 into -stable because of this
> problem.  So if you still think we should fix this in -stable, could
> you please prepare an updated patch and send it to Greg?

Will do. But let's wait for some just to be sure that is the last bug here.

>
>> Tested-by: Chris Clayton <chris2553@googlemail.com>
>> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
>> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
>> Cc: Michal Hocko <mhocko@suse.cz>
>> Cc: Rik van Riel <riel@redhat.com>

Re: [PATCH] mm: fix corner case in anon_vma endless growing prevention

[Konstantin Khlebnikov]

On Mon, Jan 12, 2015 at 11:21 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Sun, 11 Jan 2015 16:54:06 +0300 Konstantin Khlebnikov <koct9i@gmail.com> wrote:
>
>> Fix for BUG_ON(anon_vma->degree) splashes in unlink_anon_vmas()
>> ("kernel BUG at mm/rmap.c:399!").
>>
>> Anon_vma_clone() is usually called for a copy of source vma in destination
>> argument. If source vma has anon_vma it should be already in dst->anon_vma.
>> NULL in dst->anon_vma is used as a sign that it's called from anon_vma_fork().
>> In this case anon_vma_clone() finds anon_vma for reusing.
>>
>> Vma_adjust() calls it differently and this breaks anon_vma reusing logic:
>> anon_vma_clone() links vma to old anon_vma and updates degree counters but
>> vma_adjust() overrides vma->anon_vma right after that. As a result final
>> unlink_anon_vmas() decrements degree for wrong anon_vma.
>>
>> This patch assigns ->anon_vma before calling anon_vma_clone().
>>
>> Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
>> Fixes: 7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
>
> I've asked Greg not to take 7a3ef208e662 into -stable because of this
> problem.  So if you still think we should fix this in -stable, could
> you please prepare an updated patch and send it to Greg?

Will do. But let's wait for some just to be sure that is the last bug here.

>
>> Tested-by: Chris Clayton <chris2553@googlemail.com>
>> Tested-by: Oded Gabbay <oded.gabbay@amd.com>
>> Cc: Daniel Forrest <dan.forrest@ssec.wisc.edu>
>> Cc: Michal Hocko <mhocko@suse.cz>
>> Cc: Rik van Riel <riel@redhat.com>

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