Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-19 Thread Eslam Elnikety
On 14.08.19 15:02, Andrew Cooper wrote: On 14/08/2019 13:51, George Dunlap wrote: On 8/7/19 5:03 PM, Jan Beulich wrote: Whatever we do in Xen, it'll only allow to work around that issue. An actual fix belongs in the kernel(s). For this reason I suppose what we're talking about here is a

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-14 Thread Andrew Cooper
On 14/08/2019 13:51, George Dunlap wrote: > On 8/7/19 5:03 PM, Jan Beulich wrote: >> Whatever we do in Xen, it'll only allow to work around that issue. >> An actual fix belongs in the kernel(s). For this reason I suppose >> what we're talking about here is a feature (from Xen's pov), not a >> bug

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-14 Thread George Dunlap
On 8/7/19 5:03 PM, Jan Beulich wrote: > Whatever we do in Xen, it'll only allow to work around that issue. > An actual fix belongs in the kernel(s). For this reason I suppose > what we're talking about here is a feature (from Xen's pov), not a > bug fix. And it being a feature, it should

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Jan Beulich
On 07.08.2019 17:57, Andrew Cooper wrote: On 07/08/2019 16:08, Jan Beulich wrote: On 07.08.2019 17:00, Andrew Cooper wrote: On 07/08/2019 15:30, Jan Beulich wrote: On 07.08.2019 15:41, Andrew Cooper wrote: Furthermore, if there is this problem for event channels, then there is almost

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Andrew Cooper
On 07/08/2019 16:08, Jan Beulich wrote: > On 07.08.2019 17:00, Andrew Cooper wrote: >> On 07/08/2019 15:30, Jan Beulich wrote: >>> On 07.08.2019 15:41, Andrew Cooper wrote: Furthermore, if there is this problem for event channels, then there is almost certainly a related problem for

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Elnikety, Eslam
> On 7. Aug 2019, at 15:41, Andrew Cooper wrote: > > On 07/08/2019 12:20, Eslam Elnikety wrote: >> diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h >> index 19486d5e32..654b4fdd22 100644 >> --- a/xen/include/public/domctl.h >> +++ b/xen/include/public/domctl.h >> @@ -64,6

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Jan Beulich
On 07.08.2019 17:00, Andrew Cooper wrote: On 07/08/2019 15:30, Jan Beulich wrote: On 07.08.2019 15:41, Andrew Cooper wrote: Furthermore, if there is this problem for event channels, then there is almost certainly a related problem for grant tables. The control in Xen should be expressed in a

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Andrew Cooper
On 07/08/2019 15:30, Jan Beulich wrote: > On 07.08.2019 15:41, Andrew Cooper wrote: >> On 07/08/2019 12:20, Eslam Elnikety wrote: >>> diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h >>> index 19486d5e32..654b4fdd22 100644 >>> --- a/xen/include/public/domctl.h >>> +++

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Julien Grall
Hi, On 07/08/2019 15:35, Jan Beulich wrote: On 07.08.2019 13:20, Eslam Elnikety wrote: >> --- a/xen/include/xen/sched.h +++ b/xen/include/xen/sched.h @@ -338,6 +338,7 @@ struct domain struct evtchn  **evtchn_group[NR_EVTCHN_GROUPS]; /* all other buckets */ unsigned int

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Jan Beulich
On 07.08.2019 13:20, Eslam Elnikety wrote: Adding support for FIFO event channel ABI was first introduced in Xen 4.4 (see 88910061ec6). Make this support tunable, since the choice of which event channel ABI has implications for hibernation. Consider resuming a pre Xen 4.4 hibernated Linux guest.

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Jan Beulich
On 07.08.2019 15:41, Andrew Cooper wrote: On 07/08/2019 12:20, Eslam Elnikety wrote: diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h index 19486d5e32..654b4fdd22 100644 --- a/xen/include/public/domctl.h +++ b/xen/include/public/domctl.h @@ -64,6 +64,9 @@ struct

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Andrew Cooper
On 07/08/2019 12:20, Eslam Elnikety wrote: > diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h > index 19486d5e32..654b4fdd22 100644 > --- a/xen/include/public/domctl.h > +++ b/xen/include/public/domctl.h > @@ -64,6 +64,9 @@ struct xen_domctl_createdomain { > /* Is this a

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Elnikety, Eslam
> On 7. Aug 2019, at 14:30, Andrew Cooper wrote: > > On 07/08/2019 13:07, Elnikety, Eslam wrote: >>> On 7. Aug 2019, at 13:40, Andrew Cooper wrote: >>> >>> On 07/08/2019 12:20, Eslam Elnikety wrote: Adding support for FIFO event channel ABI was first introduced in Xen 4.4 (see

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Andrew Cooper
On 07/08/2019 13:07, Elnikety, Eslam wrote: >> On 7. Aug 2019, at 13:40, Andrew Cooper wrote: >> >> On 07/08/2019 12:20, Eslam Elnikety wrote: >>> Adding support for FIFO event channel ABI was first introduced in Xen 4.4 >>> (see 88910061ec6). Make this support tunable, since the choice of which

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Andrew Cooper
On 07/08/2019 13:04, Woodhouse, David wrote: > On Wed, 2019-08-07 at 12:40 +0100, Andrew Cooper wrote: >> On 07/08/2019 12:20, Eslam Elnikety wrote: >>> Adding support for FIFO event channel ABI was first introduced in Xen 4.4 >>> (see 88910061ec6). Make this support tunable, since the choice of

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Jan Beulich
On 07.08.2019 14:07, Elnikety, Eslam wrote: On 7. Aug 2019, at 13:40, Andrew Cooper wrote: On 07/08/2019 12:20, Eslam Elnikety wrote: Adding support for FIFO event channel ABI was first introduced in Xen 4.4 (see 88910061ec6). Make this support tunable, since the choice of which event

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Jan Beulich
On 07.08.2019 14:04, Woodhouse, David wrote: On Wed, 2019-08-07 at 12:40 +0100, Andrew Cooper wrote: On 07/08/2019 12:20, Eslam Elnikety wrote: Adding support for FIFO event channel ABI was first introduced in Xen 4.4 (see 88910061ec6). Make this support tunable, since the choice of which

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Elnikety, Eslam
> On 7. Aug 2019, at 13:40, Andrew Cooper wrote: > > On 07/08/2019 12:20, Eslam Elnikety wrote: >> Adding support for FIFO event channel ABI was first introduced in Xen 4.4 >> (see 88910061ec6). Make this support tunable, since the choice of which >> event channel ABI has implications for

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Woodhouse, David
On Wed, 2019-08-07 at 12:40 +0100, Andrew Cooper wrote: > On 07/08/2019 12:20, Eslam Elnikety wrote: > > Adding support for FIFO event channel ABI was first introduced in Xen 4.4 > > (see 88910061ec6). Make this support tunable, since the choice of which > > event channel ABI has implications for

Re: [Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Andrew Cooper
On 07/08/2019 12:20, Eslam Elnikety wrote: > Adding support for FIFO event channel ABI was first introduced in Xen 4.4 > (see 88910061ec6). Make this support tunable, since the choice of which > event channel ABI has implications for hibernation. Consider resuming a > pre Xen 4.4 hibernated Linux

[Xen-devel] [PATCH] evtchn: make support for different ABIs tunable

2019-08-07 Thread Eslam Elnikety
Adding support for FIFO event channel ABI was first introduced in Xen 4.4 (see 88910061ec6). Make this support tunable, since the choice of which event channel ABI has implications for hibernation. Consider resuming a pre Xen 4.4 hibernated Linux guest. The guest boot kernel defaults to FIFO ABI,