[release/9.0] Use 8.x Microsoft.Extensions.* packages

[AndriySvyryd]

Description
For 9 EF still targets net8.0 to help with adoption for users staying on the LTS SDK, but we depend on 9.0.x versions of Microsoft.Extensions.* packages.

Customer impact
When deploying an app targeting net8.0, the Microsoft.Extensions.* packages will be deployed too instead of using the shared framework.

How found
Reported on 9 RC1 by partner team (Aspire - dotnet/aspire#5932 (review)).

Regression
No

Testing
Tested manually

Risk
Low.

[sebastienros]

What is the reason to run benchmarks and tests with 9.0 dependencies?
Are the tests run in both 8 and 9? Could only find DefaultNetCoreTargetFramework in a random test csproj.

[AndriySvyryd]

What is the reason to run benchmarks and tests with 9.0 dependencies?

That's still the mainline scenario for EF Core 9

Are the tests run in both 8 and 9? Could only find DefaultNetCoreTargetFramework in a random test csproj.

No, I tested it manually for net8.0 with 8.0.x dependencies. Multi-targeting all the tests is non-trivial and something that would only apply to this release.

[artl93]

@AndriySvyryd, @ericstj and I were chatting - what's the servicing story here when .NET 8 ship an MSRC fix and entity framework in 9.0 needs to sim-ship that fix?

[AndriySvyryd]

@artl93 You mean that one of the 8.0.x dependencies needs to be updated at the same time it's shipped?
@mmitche can correct me here, but we already consume the dotnet8 feed when building EF Core 9, so it should be just a matter of scheduling the builds in the correct order.

[ericstj]

i'm not sure what the process is for entity framework, but for the rest of the product we don't flow changes across bands. Doing so would delay builds in later versions and reset them when earlier versions rebuild. We also try to avoid these dependencies for source build, because they require explicit reference packages. Again I'm not sure if that would apply to entity framework or not.

Boils down to what sort of package is entity framework. Is it part of .net versioning and servicing with .net or is it something on top?

[AndriySvyryd]

Boils down to what sort of package is entity framework. Is it part of .net versioning and servicing with .net or is it something on top?

EF Core is shipped and serviced following the same schedule as .NET, but it's not part of source build, SDK or VS

[AndriySvyryd]

Closing as the servicing cost would be prohibitive.