Re: [RESEND v2 PATCH 0/2] Bug fix in aio ring page migration

Re: [RESEND v2 PATCH 0/2] Bug fix in aio ring page migration

[Gu Zheng]

This patchset has been applied to linux-next, and these problems also exist
in 3.12.y and 3.13.y stable tree.
So please merge this patchset to 3.12.y and 3.13.y stable tree.

commit 692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
Author: Tang Chen <tangchen@cn.fujitsu.com>
Date:   Mon Mar 10 16:15:33 2014 +0800

    aio, memory-hotplug: Fix confliction when migrating and accessing ring pages.

commit e0f5e0add36d2e3c456cf2f4283673ed834b3c24
Author: Tang Chen <tangchen@cn.fujitsu.com>
Date:   Mon Mar 10 16:15:34 2014 +0800

    aio, mem-hotplug: Add memory barrier to aio ring page migration.

https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/fs/aio.c?id=692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/fs/aio.c?id=e0f5e0add36d2e3c456cf2f4283673ed834b3c24

https://lkml.org/lkml/2014/3/10/56
https://lkml.org/lkml/2014/3/10/58


On 03/10/2014 04:15 PM, Tang Chen wrote:

> This patch-set fixes the following two problems:
> 
> 1. Need to use ctx->completion_lock to protect ring pages
>    from being mis-written while migration.
> 
> 2. Need memory barrier to ensure memory copy is done before
>    ctx->ring_pages[] is updated.
> 
> NOTE: AIO ring page migration was implemented since Linux 3.12.
>       So we need to merge these two patches into 3.12 stable tree.
> 
> Tang Chen (2):
>   aio, memory-hotplug: Fix confliction when migrating and accessing
>     ring pages.
>   aio, mem-hotplug: Add memory barrier to aio ring page migration.
> 
>  fs/aio.c |   42 ++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 42 insertions(+), 0 deletions(-)
> 

Re: [RESEND v2 PATCH 0/2] Bug fix in aio ring page migration

[Ben Hutchings]

[-- Attachment #1: Type: text/plain, Size: 852 bytes --]

On Thu, 2014-03-13 at 17:45 +0800, Gu Zheng wrote:
> This patchset has been applied to linux-next, and these problems also exist
> in 3.12.y and 3.13.y stable tree.
> So please merge this patchset to 3.12.y and 3.13.y stable tree.

They must be in Linus's tree before they are acceptable for stable.

Ben.

> commit 692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
> Author: Tang Chen <tangchen@cn.fujitsu.com>
> Date:   Mon Mar 10 16:15:33 2014 +0800
> 
>     aio, memory-hotplug: Fix confliction when migrating and accessing ring pages.
> 
> commit e0f5e0add36d2e3c456cf2f4283673ed834b3c24
> Author: Tang Chen <tangchen@cn.fujitsu.com>
> Date:   Mon Mar 10 16:15:34 2014 +0800
> 
>     aio, mem-hotplug: Add memory barrier to aio ring page migration.
[...]

-- 
Ben Hutchings
Computers are not intelligent.	They only think they are.

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 811 bytes --]

Re: [RESEND v2 PATCH 0/2] Bug fix in aio ring page migration

[Greg Kroah-Hartman]

On Thu, Mar 13, 2014 at 05:45:42PM +0800, Gu Zheng wrote:
> This patchset has been applied to linux-next, and these problems also exist
> in 3.12.y and 3.13.y stable tree.
> So please merge this patchset to 3.12.y and 3.13.y stable tree.
> 
> commit 692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
> Author: Tang Chen <tangchen@cn.fujitsu.com>
> Date:   Mon Mar 10 16:15:33 2014 +0800
> 
>     aio, memory-hotplug: Fix confliction when migrating and accessing ring pages.
> 
> commit e0f5e0add36d2e3c456cf2f4283673ed834b3c24
> Author: Tang Chen <tangchen@cn.fujitsu.com>
> Date:   Mon Mar 10 16:15:34 2014 +0800
> 
>     aio, mem-hotplug: Add memory barrier to aio ring page migration.
> 
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/fs/aio.c?id=692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/fs/aio.c?id=e0f5e0add36d2e3c456cf2f4283673ed834b3c24
> 
> https://lkml.org/lkml/2014/3/10/56
> https://lkml.org/lkml/2014/3/10/58

I don't see these in Linus's tree, what happened?

thanks,

greg k-h

Re: [RESEND v2 PATCH 0/2] Bug fix in aio ring page migration

[Gu Zheng]

Hi Greg,
Thanks for your attention on this thread.
On 05/14/2014 07:58 AM, Greg Kroah-Hartman wrote:

> On Thu, Mar 13, 2014 at 05:45:42PM +0800, Gu Zheng wrote:
>> This patchset has been applied to linux-next, and these problems also exist
>> in 3.12.y and 3.13.y stable tree.
>> So please merge this patchset to 3.12.y and 3.13.y stable tree.
>>
>> commit 692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
>> Author: Tang Chen <tangchen@cn.fujitsu.com>
>> Date:   Mon Mar 10 16:15:33 2014 +0800
>>
>>     aio, memory-hotplug: Fix confliction when migrating and accessing ring pages.
>>
>> commit e0f5e0add36d2e3c456cf2f4283673ed834b3c24
>> Author: Tang Chen <tangchen@cn.fujitsu.com>
>> Date:   Mon Mar 10 16:15:34 2014 +0800
>>
>>     aio, mem-hotplug: Add memory barrier to aio ring page migration.
>>
>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/fs/aio.c?id=692c9b8c5ee8d263bb8348171f0bebd3d84eb2c1
>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/fs/aio.c?id=e0f5e0add36d2e3c456cf2f4283673ed834b3c24
>>
>> https://lkml.org/lkml/2014/3/10/56
>> https://lkml.org/lkml/2014/3/10/58
> 
> I don't see these in Linus's tree, what happened?

These two patches were replaced by the better one from Benjamin, and it has been
merged into upstream.
commit fa8a53c39f3fdde98c9eace6a9b412143f0f6ed6
Author: Benjamin LaHaise <bcrl@kvack.org>
Date:   Fri Mar 28 10:14:45 2014 -0400

    aio: v4 ensure access to ctx->ring_pages is correctly serialised for migration
And I have already received the notify that it has been applied into stable tree.

Best regards,
Gu

> 
> thanks,
> 
> greg k-h
> 
> --
> To unsubscribe, send a message with 'unsubscribe linux-aio' in
> the body to majordomo@kvack.org.  For more info on Linux AIO,
> see: http://www.kvack.org/aio/
> Don't email: <a href=mailto:"aart@kvack.org">aart@kvack.org</a>
> .
>