>>> On 07.03.19 at 10:11, <jgr...@suse.com> wrote:
> Commit f7c90c2aa40048 ("x86/xen: don't write ptes directly in 32-bit
> PV guests") introduced a regression for booting dom0 on huge systems
> with lots of RAM (in the TB range).
>
> Reason is that on those hosts the p2m list needs to be moved early in
> the boot process and this requires temporary page tables to be created.
> Said commit modified xen_set_pte_init() to use a hypercall for writing
> a PTE, but this requires the page table being in the direct mapped
> area, which is not the case for the temporary page tables used in
> xen_relocate_p2m().
>
> As the page tables are completely written before being linked to the
> actual address space instead of set_pte() a plain write to memory can
> be used in xen_relocate_p2m().
>
> Fixes: f7c90c2aa40048 ("x86/xen: don't write ptes directly in 32-bit PV
> guests")
> Signed-off-by: Juergen Gross <jgr...@suse.com>
Reviewed-by: Jan Beulich <jbeul...@suse.com>
