ACK: [SRU focal/linux-gcp 0/1] LP: #1958416 (IO failures on SEV GCP instances)

[Stefan Bader]

On 10.11.22 10:53, Thadeu Lima de Souza Cascardo wrote:
> On Thu, Nov 10, 2022 at 10:00:31AM +0100, Stefan Bader wrote:
>> On 09.11.22 18:06, Thadeu Lima de Souza Cascardo wrote:
>>> [Impact]
>>> Small SWIOTLB might cause DMA failures during High IO on GCP instances using SEV.
>>>
>>> [Test case]
>>> Boot n2d-standard-2 or n2d-standard-64 instances on GCP, issue a lot of IO,
>>> and look for DMA overflow or full swiotlb messages on dmesg.
>>>
>>> [Potential regression]
>>> Boot failures should not be discarded when SWIOTLB cannot be allocated.
>>>
>>> Ashish Kalra (1):
>>>     x86,swiotlb: Adjust SWIOTLB bounce buffer size for SEV guests
>>>
>>>    arch/x86/include/asm/mem_encrypt.h |  2 ++
>>>    arch/x86/kernel/setup.c            |  6 ++++++
>>>    arch/x86/mm/mem_encrypt.c          | 31 ++++++++++++++++++++++++++++++
>>>    include/linux/swiotlb.h            |  8 ++++++++
>>>    kernel/dma/swiotlb.c               | 20 +++++++++++++++++--
>>>    5 files changed, 65 insertions(+), 2 deletions(-)
>>>
>>
>> Hm, is this really only needed for the gcp kernel? Are we not also run tests
>> for the focal:linux kernel on the GCP cloud?
>>
>> -Stefan
>>
> 
> I just added in the LP bug the target to linux as Medium, while linux-gcp is
> High. As linux-gcp has other changes to those files that make it a different
> backport, I opted to prioritizing the fix in linux-gcp.
> 
> Cascardo.

Ah, ok. Thanks for the explanation.

Acked-by: Stefan Bader <stefan.bader at canonical.com>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <https://lists.ubuntu.com/archives/kernel-team/attachments/20221110/4862c5cb/attachment.sig>