Re: [Xen-devel] [PATCH v2 2/4] xen-blkback: fix memory leaks

Re: [Xen-devel] [PATCH v2 2/4] xen-blkback: fix memory leaks

[Egger, Christoph]

On 07.02.14 04:15, Matthew Rushton wrote:
> On 04/02/14 10:26, Roger Pau Monne wrote:
>> I've at least identified two possible memory leaks in blkback, both
>> related to the shutdown path of a VBD:
>> 
>> - blkback doesn't wait for any pending purge work to finish before
>>   cleaning the list of free_pages. The purge work will call
>>   put_free_pages and thus we might end up with pages being added to
>>   the free_pages list after we have emptied it. Fix this by making
>>   sure there's no pending purge work before exiting
>>   xen_blkif_schedule, and moving the free_page cleanup code to
>>   xen_blkif_free.
>> - blkback doesn't wait for pending requests to end before cleaning
>>   persistent grants and the list of free_pages. Again this can add
>>   pages to the free_pages list or persistent grants to the
>>   persistent_gnts red-black tree. Fixed by moving the persistent
>>   grants and free_pages cleanup code to xen_blkif_free.
>> 
>> Also, add some checks in xen_blkif_free to make sure we are cleaning
>> everything.
> 
> Tested-by: Matt Rushton <mrushton@amazon.com>
> Reviewed-by: Matt Rushton <mrushton@amazon.com>

Tested-by: Christoph Egger <chegger@amazon.de>
Reviewed-by: Christoph Egger <chegger@amazon.de>

Christoph