Re: [PATCH v1] drivers/base/memory: add memory block to memory group after registration succeeded

From: David Hildenbrand
Date: Tue Feb 01 2022 - 03:16:17 EST


On 01.02.22 02:01, Andrew Morton wrote:
> On Fri, 28 Jan 2022 15:45:40 +0100 David Hildenbrand <david@xxxxxxxxxx> wrote:
>
>> If register_memory() fails, we freed the memory block but already added
>> the memory block to the group list, not good. Let's defer adding the
>> block to the memory group to after registering the memory block device.
>>
>> We do handle it properly during unregister_memory(), but that's not
>> called when the registration fails.
>>
>
> I guess this has never been known to happen. So I queued the fix for
> 5.18-rc1, cc:stable.

Triggering that registration error is fairly hard, usually we fail
memory hotplug because we fail to allocate the (largish) memmap. So I am
not aware that this BUG actually triggered.

--
Thanks,

David / dhildenb