Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-03 Thread Jan Beulich
>>> On 02.12.15 at 18:14, wrote: > On 02/12/15 16:46, Tim Deegan wrote: >> At 16:30 + on 02 Dec (1449073841), George Dunlap wrote: >>> On 02/12/15 16:23, Tim Deegan wrote: At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: >> From: David Vrabel

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-03 Thread George Dunlap
On Thu, Dec 3, 2015 at 10:22 AM, Jan Beulich wrote: On 02.12.15 at 18:14, wrote: >> On 02/12/15 16:46, Tim Deegan wrote: >>> At 16:30 + on 02 Dec (1449073841), George Dunlap wrote: On 02/12/15 16:23, Tim Deegan wrote: > At 07:25 +

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread Tim Deegan
At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: > > From: David Vrabel [mailto:david.vra...@citrix.com] > > Sent: Saturday, November 14, 2015 2:50 AM > > > > If a page is freed without translations being invalidated, and the page is > > subsequently allocated to another domain, a guest

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread George Dunlap
On 02/12/15 16:23, Tim Deegan wrote: > At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: >>> From: David Vrabel [mailto:david.vra...@citrix.com] >>> Sent: Saturday, November 14, 2015 2:50 AM >>> >>> If a page is freed without translations being invalidated, and the page is >>> subsequently

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread David Vrabel
On 02/12/15 16:23, Tim Deegan wrote: > At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: >>> From: David Vrabel [mailto:david.vra...@citrix.com] >>> Sent: Saturday, November 14, 2015 2:50 AM >>> >>> If a page is freed without translations being invalidated, and the page is >>> subsequently

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread George Dunlap
On 02/12/15 16:46, Tim Deegan wrote: > At 16:30 + on 02 Dec (1449073841), George Dunlap wrote: >> On 02/12/15 16:23, Tim Deegan wrote: >>> At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: > From: David Vrabel [mailto:david.vra...@citrix.com] > Sent: Saturday, November 14, 2015

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread Tim Deegan
At 16:30 + on 02 Dec (1449073841), George Dunlap wrote: > On 02/12/15 16:23, Tim Deegan wrote: > > At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: > >>> From: David Vrabel [mailto:david.vra...@citrix.com] > >>> Sent: Saturday, November 14, 2015 2:50 AM > >>> > >>> If a page is freed

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread David Vrabel
On 02/12/15 16:46, Tim Deegan wrote: > At 16:30 + on 02 Dec (1449073841), George Dunlap wrote: >> On 02/12/15 16:23, Tim Deegan wrote: >>> At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: > From: David Vrabel [mailto:david.vra...@citrix.com] > Sent: Saturday, November 14, 2015

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread George Dunlap
On 02/12/15 16:45, David Vrabel wrote: > On 02/12/15 16:23, Tim Deegan wrote: >> At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: From: David Vrabel [mailto:david.vra...@citrix.com] Sent: Saturday, November 14, 2015 2:50 AM If a page is freed without translations being

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-02 Thread Jan Beulich
>>> On 02.12.15 at 17:30, wrote: > On 02/12/15 16:23, Tim Deegan wrote: >> At 07:25 + on 02 Dec (1449041100), Tian, Kevin wrote: From: David Vrabel [mailto:david.vra...@citrix.com] Sent: Saturday, November 14, 2015 2:50 AM If a page is freed

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-12-01 Thread Tian, Kevin
> From: David Vrabel [mailto:david.vra...@citrix.com] > Sent: Saturday, November 14, 2015 2:50 AM > > If a page is freed without translations being invalidated, and the page is > subsequently allocated to another domain, a guest with a cached > translation will still be able to access the page. >

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-11-16 Thread Jan Beulich
>>> On 16.11.15 at 13:02, wrote: > On 16/11/15 11:52, Jan Beulich wrote: > On 13.11.15 at 19:49, wrote: >>> @@ -2805,6 +2806,9 @@ int p2m_add_foreign(struct domain *tdom, unsigned >>> long > fgfn, >>> prev_mfn = mfn_x(get_gfn(tdom,

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-11-16 Thread David Vrabel
On 16/11/15 11:52, Jan Beulich wrote: On 13.11.15 at 19:49, wrote: >> @@ -2805,6 +2806,9 @@ int p2m_add_foreign(struct domain *tdom, unsigned long >> fgfn, >> prev_mfn = mfn_x(get_gfn(tdom, gpfn, _prev)); >> if ( mfn_valid(_mfn(prev_mfn)) ) >> { >> +

Re: [Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-11-16 Thread Jan Beulich
>>> On 13.11.15 at 19:49, wrote: > @@ -2805,6 +2806,9 @@ int p2m_add_foreign(struct domain *tdom, unsigned long > fgfn, > prev_mfn = mfn_x(get_gfn(tdom, gpfn, _prev)); > if ( mfn_valid(_mfn(prev_mfn)) ) > { > +prev_page =

[Xen-devel] [PATCHv2 2/3] mm: don't free pages until mm locks are released

2015-11-13 Thread David Vrabel
If a page is freed without translations being invalidated, and the page is subsequently allocated to another domain, a guest with a cached translation will still be able to access the page. Currently translations are invalidated before releasing the page ref, but while still holding the mm locks.