On 20.11.20 16:13, Cornelia Huck wrote:
> On Mon, 16 Nov 2020 20:16:29 +0100
> David Hildenbrand <> wrote:
>
>> Let's clarify that we don't expect all DMA to work with unplugged blocks.
>> We really only give guarantees when reading from unplugged memory blocks
>> via the CPU, e.g., as done by Linux when creating a system dump via
>> kdump: the new kernel will copy the content of the old (crashed) kernel
>> via the CPU to user space, from where it will find its final destination
>> inside the dump file. Note that dumping via makedumpfile under Linux will
>> avoid reading unplugged blocks completely.
>>
>> This is a preparation for device passthrough to VMs, whereby such
>> dedicated devices might not be able to read from unplugged memory blocks.
>>
>> Let's document that this scenario is possible, and why this handling is
>> in place at all.
>>
>> Cc: teawater <>
>> Cc: Marek Kedzierski <>
>> Cc: Michael S. Tsirkin <>
>> Cc: Cornelia Huck <>
>> Signed-off-by: David Hildenbrand <>
>> ---
>> virtio-mem.tex | 9 +++++++--
>> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> Looks reasonable to me.
>
> Acked-by: Cornelia Huck <>
Thanks!
I assume I'll need a github issue etc. to get this in, right?
--
Thanks,
David / dhildenb
