[SRU,v2,0/1,G/aws,F/aws,B/aws,X/aws] aws: properly

BugLink: https://bugs.launchpad.net/bugs/1913739

[Impact]

To properly support instance types in AWS with > 255 cores we need to
make sure that commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b
("iommu/vt-d: Gracefully handle DMAR units with no supported address widths")
is applied across all our linux-aws kernels.

[Test Case]

Tests performed by AWS.

[Fix]

Apply/backport commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b.

[Regression potential]

The fix is affecting only intel IOMMU and it is an upstream fix, so the
regression potential should be minimal.

Changes v1 -> v2:
 - include patches for G/aws and X/aws

Subject was truncated (my mistake). The right subject shoudld be:

 [SRU][PATCH v2 0/1][G/aws, F/aws, B/aws, X/aws] aws: properly support instance types with > 255 cpu cores

(same as the title of LP: #1913739.

Sorry for the confusion.

-Andrea

LGTM.

Acked-by: Kamal Mostafa <kamal@canonical.com>

 -Kamal

On Mon, Feb 01, 2021 at 03:29:04PM +0100, Andrea Righi wrote:
> BugLink: https://bugs.launchpad.net/bugs/1913739
> 
> [Impact]
> 
> To properly support instance types in AWS with > 255 cores we need to
> make sure that commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b
> ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths")
> is applied across all our linux-aws kernels.
> 
> [Test Case]
> 
> Tests performed by AWS.
> 
> [Fix]
> 
> Apply/backport commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b.
> 
> [Regression potential]
> 
> The fix is affecting only intel IOMMU and it is an upstream fix, so the
> regression potential should be minimal.
> 
> Changes v1 -> v2:
>  - include patches for G/aws and X/aws
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team

On 01.02.21 15:29, Andrea Righi wrote:
> BugLink: https://bugs.launchpad.net/bugs/1913739
> 
> [Impact]
> 
> To properly support instance types in AWS with > 255 cores we need to
> make sure that commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b
> ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths")
> is applied across all our linux-aws kernels.
> 
> [Test Case]
> 
> Tests performed by AWS.
> 
> [Fix]
> 
> Apply/backport commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b.
> 
> [Regression potential]
> 
> The fix is affecting only intel IOMMU and it is an upstream fix, so the
> regression potential should be minimal.
> 
> Changes v1 -> v2:
>  - include patches for G/aws and X/aws
> 
> 
The cherry pick seems plausible and the backports matching the  cherry pick (a
short hint about what had to change would be nice).

The bug report lacked consistency in status and importance settings (and what
about Hirsute? Assuming it does not yet exist separately then its invalid.
Also the "regression potential" is not quite right. It should say what a
possible regression would look like, not how likely it is thought to be.

The patches themselves are ok, so

Acked-by: Stefan Bader <stefan.bader@canonical.com>

But you should fix up the bug report.

-Stefan

On Tue, Feb 02, 2021 at 09:17:04AM +0100, Stefan Bader wrote:
> On 01.02.21 15:29, Andrea Righi wrote:
> > BugLink: https://bugs.launchpad.net/bugs/1913739
> > 
> > [Impact]
> > 
> > To properly support instance types in AWS with > 255 cores we need to
> > make sure that commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b
> > ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths")
> > is applied across all our linux-aws kernels.
> > 
> > [Test Case]
> > 
> > Tests performed by AWS.
> > 
> > [Fix]
> > 
> > Apply/backport commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b.
> > 
> > [Regression potential]
> > 
> > The fix is affecting only intel IOMMU and it is an upstream fix, so the
> > regression potential should be minimal.
> > 
> > Changes v1 -> v2:
> >  - include patches for G/aws and X/aws
> > 
> > 
> The cherry pick seems plausible and the backports matching the  cherry pick (a
> short hint about what had to change would be nice).
> 
> The bug report lacked consistency in status and importance settings (and what
> about Hirsute? Assuming it does not yet exist separately then its invalid.
> Also the "regression potential" is not quite right. It should say what a
> possible regression would look like, not how likely it is thought to be.
> 
> The patches themselves are ok, so
> 
> Acked-by: Stefan Bader <stefan.bader@canonical.com>
> 
> But you should fix up the bug report.

Thanks for the review, Stefan.

I changed the bug description (LP: #1913739) adding more details about
the backporting activity that was done and also changed the description
of "regression potential".

I also removed "hirsute", because it doesn't require this patch at the
moment (it'll automatically get this patch when we'll move to 5.10).

-Andrea

Applied to:
 groovy/linux-aws
 focal/linux-aws
 bionic/linux-aws
 xenial/linux-aws

Thanks,
Ian

On 2021-02-01 15:29:04 , Andrea Righi wrote:
> BugLink: https://bugs.launchpad.net/bugs/1913739
> 
> [Impact]
> 
> To properly support instance types in AWS with > 255 cores we need to
> make sure that commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b
> ("iommu/vt-d: Gracefully handle DMAR units with no supported address widths")
> is applied across all our linux-aws kernels.
> 
> [Test Case]
> 
> Tests performed by AWS.
> 
> [Fix]
> 
> Apply/backport commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b.
> 
> [Regression potential]
> 
> The fix is affecting only intel IOMMU and it is an upstream fix, so the
> regression potential should be minimal.
> 
> Changes v1 -> v2:
>  - include patches for G/aws and X/aws
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team