Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-06-21 Thread Susheel Khiani
On 6/9/2015 11:56 PM, Susheel Khiani wrote: On 4/30/2015 11:37 AM, Susheel Khiani wrote: But if I've misunderstood, and you think that what you're seeing fits with the transient forking bugs I've (not quite) described, and you can explain why even the transient case is important for you to have

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-06-21 Thread Susheel Khiani
On 6/9/2015 11:56 PM, Susheel Khiani wrote: On 4/30/2015 11:37 AM, Susheel Khiani wrote: But if I've misunderstood, and you think that what you're seeing fits with the transient forking bugs I've (not quite) described, and you can explain why even the transient case is important for you to have

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-06-09 Thread Susheel Khiani
On 4/30/2015 11:37 AM, Susheel Khiani wrote: But if I've misunderstood, and you think that what you're seeing fits with the transient forking bugs I've (not quite) described, and you can explain why even the transient case is important for you to have fixed, then I really ought to redouble my

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-06-09 Thread Susheel Khiani
On 4/30/2015 11:37 AM, Susheel Khiani wrote: But if I've misunderstood, and you think that what you're seeing fits with the transient forking bugs I've (not quite) described, and you can explain why even the transient case is important for you to have fixed, then I really ought to redouble my

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-04-30 Thread Susheel Khiani
On 04/15/15 11:52, Hugh Dickins wrote: We are using kernel-3.10.49 and I have gone through patches of ksm above this >kernel version but didn't find anything relevant w.r.t issue. The latest >patch which we have for KSM on our tree is > >668f9abb: mm: close PageTail race I agree, I don't think

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-04-30 Thread Susheel Khiani
On 04/15/15 11:52, Hugh Dickins wrote: We are using kernel-3.10.49 and I have gone through patches of ksm above this kernel version but didn't find anything relevant w.r.t issue. The latest patch which we have for KSM on our tree is 668f9abb: mm: close PageTail race I agree, I don't think

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-04-15 Thread Hugh Dickins
On Tue, 14 Apr 2015, Susheel Khiani wrote: > On 04/10/15 23:26, Hugh Dickins wrote: > > On Thu, 9 Apr 2015, Susheel Khiani wrote: > > > > > > We are seeing an issue during try_to_unmap_ksm where in call to > > > try_to_unmap_one is failing. > > > > > > try_to_unmap_ksm in this particular case is

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-04-15 Thread Hugh Dickins
On Tue, 14 Apr 2015, Susheel Khiani wrote: On 04/10/15 23:26, Hugh Dickins wrote: On Thu, 9 Apr 2015, Susheel Khiani wrote: We are seeing an issue during try_to_unmap_ksm where in call to try_to_unmap_one is failing. try_to_unmap_ksm in this particular case is trying to go

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-04-14 Thread Susheel Khiani
On 04/10/15 23:26, Hugh Dickins wrote: On Thu, 9 Apr 2015, Susheel Khiani wrote: Hi, We are seeing an issue during try_to_unmap_ksm where in call to try_to_unmap_one is failing. try_to_unmap_ksm in this particular case is trying to go through vmas associated with each rmap_item->anon_vma.

Re: [Question] ksm: rmap_item pointing to some stale vmas

2015-04-14 Thread Susheel Khiani
On 04/10/15 23:26, Hugh Dickins wrote: On Thu, 9 Apr 2015, Susheel Khiani wrote: Hi, We are seeing an issue during try_to_unmap_ksm where in call to try_to_unmap_one is failing. try_to_unmap_ksm in this particular case is trying to go through vmas associated with each rmap_item-anon_vma.

[Question] ksm: rmap_item pointing to some stale vmas

2015-04-09 Thread Susheel Khiani
Hi, We are seeing an issue during try_to_unmap_ksm where in call to try_to_unmap_one is failing. try_to_unmap_ksm in this particular case is trying to go through vmas associated with each rmap_item->anon_vma. What we see is this that the corresponding page is not mapped to any of the vmas

[Question] ksm: rmap_item pointing to some stale vmas

2015-04-09 Thread Susheel Khiani
Hi, We are seeing an issue during try_to_unmap_ksm where in call to try_to_unmap_one is failing. try_to_unmap_ksm in this particular case is trying to go through vmas associated with each rmap_item-anon_vma. What we see is this that the corresponding page is not mapped to any of the vmas