Re: [PATCH] xen/balloon: Mark unallocated host memory as UNUSABLE

From: Boris Ostrovsky
Date: Fri Dec 15 2017 - 09:29:30 EST



>> +
>> + hostmem_resource->start = max_addr;
>> + hostmem_resource->end = entry->addr + entry->size;
>> + for (; i < memmap.nr_entries; i++) {
>> + entry = &xen_e820_table->entries[i];
>> + if (entry->type == E820_TYPE_RAM)
> Shouldn't that be != ?

No, the idea here is to populate hostmem_resource with ranges already
taken by things other than RAM, leaving memory regions as available for
the balloon hotplug. This will allow us to use allocate_resource(),
which searches for a free range, in the balloon driver.


>
>> + continue;
>> +
>> + res = kzalloc(sizeof(*res), GFP_KERNEL);
>> + if (!res) {
>> + pr_warn("%s: Out of memory\n", __func__);
> Don't print error message in case of allocation failures.

Right, In fact checkpatch also suggested that I drop it. And I forgot.


-boris