Hi Jan, On 05/07/2021 09:41, Jan Beulich wrote:
On 03.07.2021 19:11, Julien Grall wrote:Changes in v5: - Removed the #ifdef CONFIG_X86 as they are not necessary anymore - Used paging_mode_translate() rather than is_pv_domain()Is there a particular reason you use this in favor of steal_page()'s paging_mode_external()?
This is what you suggested in v4 [1]. I can switch to paging_mode_external() if this is what you now prefer.
@@ -815,6 +812,9 @@ static long memory_exchange(XEN_GUEST_HANDLE_PARAM(xen_memory_exchange_t) arg) if ( __copy_field_to_guest(arg, &exch, nr_exchanged) ) rc = -EFAULT;I'm afraid that for correctness of the interface you need to keep this part even in the !PV case.
Xen never initializes the field nr_exchanged. Instead, it expects the guest to set to 0. So I am not quite to sure why we would need to keep this line.
Seeing the 2nd use of steal_page() I wonder if it was too much to ask you to do a similar transformation for gnttab_transfer(), even if it's not directly related to the immediate purpose of this series. If you're not going to do so, I guess I'd put it on my list (perhaps together with moving x86'es steal_page() and dropping Arm's stub).
I will have a look to #ifdef the code in gnttab_transfer() and drop steal_page() on Arm.
Cheers, [1] <[email protected]> -- Julien Grall
