[Qemu-devel] Re: [PATCH 4/8] kvm: Rework dirty bitmap synchronization

[Avi Kivity]

Jan Kiszka wrote:
> Extend kvm_physical_sync_dirty_bitmap() so that is can sync across
> multiple slots. Useful for updating the whole dirty log during
> migration. Moreover, properly pass down errors the whole call chain.
>
>  
> -void cpu_physical_sync_dirty_bitmap(target_phys_addr_t start_addr, target_phys_addr_t end_addr);
> +int cpu_physical_sync_dirty_bitmap(target_phys_addr_t start_addr,
> +                                   target_phys_addr_t end_addr);
>  
>   

This is defined in terms of physical addresses, but in patch 5, you

> @@ -3248,13 +3248,18 @@ static int ram_save_live(QEMUFile *f, int stage, void 
> *opaque)
>  {
>      ram_addr_t addr;
>  
> +    if (cpu_physical_sync_dirty_bitmap(0, last_ram_offset) != 0) {
> +        qemu_file_set_error(f);
> +        return 0;
> +    }
> +
>     

Which is in terms of ram addresses; so this will fail with large memory, 
where the last phys address is larger than the last ram address.

Maybe this can be as easy as passing -1 for the end address.  But in 
this case I suggest adding a helper to sync all of memory instead.

--
error compiling committee.c: too many arguments to function