Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-31 Thread Juergen Gross
On 31.08.22 18:02, Alex Bennée wrote: Juergen Gross writes: [[PGP Signed Part:Undecided]] On 24.08.22 17:58, Alex Bennée wrote: Juergen Gross writes: [[PGP Signed Part:Undecided]] On 24.08.22 13:22, Alex Bennée wrote: Andrew Cooper writes: On 24/08/2022 10:19, Viresh Kumar wrote: On

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-31 Thread Alex Bennée
Juergen Gross writes: > [[PGP Signed Part:Undecided]] > On 24.08.22 17:58, Alex Bennée wrote: >> Juergen Gross writes: >> >>> [[PGP Signed Part:Undecided]] >>> On 24.08.22 13:22, Alex Bennée wrote: Andrew Cooper writes: > On 24/08/2022 10:19, Viresh Kumar wrote: >> On 24-03

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Juergen Gross
On 24.08.22 17:58, Alex Bennée wrote: Juergen Gross writes: [[PGP Signed Part:Undecided]] On 24.08.22 13:22, Alex Bennée wrote: Andrew Cooper writes: On 24/08/2022 10:19, Viresh Kumar wrote: On 24-03-22, 06:12, Juergen Gross wrote: For a rather long time we were using "normal" user page

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Alex Bennée
Juergen Gross writes: > [[PGP Signed Part:Undecided]] > On 24.08.22 13:22, Alex Bennée wrote: >> Andrew Cooper writes: >> >>> On 24/08/2022 10:19, Viresh Kumar wrote: On 24-03-22, 06:12, Juergen Gross wrote: > For a rather long time we were using "normal" user pages for this purpose,

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Juergen Gross
On 24.08.22 13:47, Alex Bennée wrote: Juergen Gross writes: [[PGP Signed Part:Undecided]] On 24.08.22 11:19, Viresh Kumar wrote: On 24-03-22, 06:12, Juergen Gross wrote: For a rather long time we were using "normal" user pages for this purpose, which were just locked into memory for doing t

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Juergen Gross
On 24.08.22 13:22, Alex Bennée wrote: Andrew Cooper writes: On 24/08/2022 10:19, Viresh Kumar wrote: On 24-03-22, 06:12, Juergen Gross wrote: For a rather long time we were using "normal" user pages for this purpose, which were just locked into memory for doing the hypercall. Unfortunately

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Alex Bennée
Juergen Gross writes: > [[PGP Signed Part:Undecided]] > On 24.08.22 11:19, Viresh Kumar wrote: >> On 24-03-22, 06:12, Juergen Gross wrote: >>> For a rather long time we were using "normal" user pages for this purpose, >>> which were just locked into memory for doing the hypercall. >>> >>> Unfor

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Alex Bennée
Andrew Cooper writes: > On 24/08/2022 10:19, Viresh Kumar wrote: >> On 24-03-22, 06:12, Juergen Gross wrote: >>> For a rather long time we were using "normal" user pages for this purpose, >>> which were just locked into memory for doing the hypercall. >>> >>> Unfortunately there have been very

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Juergen Gross
On 24.08.22 11:19, Viresh Kumar wrote: On 24-03-22, 06:12, Juergen Gross wrote: For a rather long time we were using "normal" user pages for this purpose, which were just locked into memory for doing the hypercall. Unfortunately there have been very rare problems with that approach, as the Linu

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-08-24 Thread Viresh Kumar
On 24-03-22, 06:12, Juergen Gross wrote: > For a rather long time we were using "normal" user pages for this purpose, > which were just locked into memory for doing the hypercall. > > Unfortunately there have been very rare problems with that approach, as > the Linux kernel can set a user page rel

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-03-27 Thread Juergen Gross
On 25.03.22 17:07, Alex Bennée wrote: (add Arnd to CC) Juergen Gross writes: [[PGP Signed Part:Undecided]] On 24.03.22 02:42, Stefano Stabellini wrote: I am pretty sure the reasons have to do with old x86 PV guests, so I am CCing Juergen and Boris. Hi, While we've been working on the rus

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-03-25 Thread Alex Bennée
(add Arnd to CC) Juergen Gross writes: > [[PGP Signed Part:Undecided]] > On 24.03.22 02:42, Stefano Stabellini wrote: >> I am pretty sure the reasons have to do with old x86 PV guests, so I am >> CCing Juergen and Boris. >> >>> Hi, >>> >>> While we've been working on the rust-vmm virtio backe

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-03-23 Thread Juergen Gross
On 24.03.22 02:42, Stefano Stabellini wrote: I am pretty sure the reasons have to do with old x86 PV guests, so I am CCing Juergen and Boris. Hi, While we've been working on the rust-vmm virtio backends on Xen we obviously have to map guest memory info the userspace of the daemon. However fol

Re: Understanding osdep_xenforeignmemory_map mmap behaviour

2022-03-23 Thread Stefano Stabellini
I am pretty sure the reasons have to do with old x86 PV guests, so I am CCing Juergen and Boris. > Hi, > > While we've been working on the rust-vmm virtio backends on Xen we > obviously have to map guest memory info the userspace of the daemon. > However following the logic of what is going on i