Generate CORE_ROOT failing for linux_musl arm/arm64

[kunalspathak]

The outerloop CI is failing on Linux_musl arm/arm64 while generating CORE_ROOT blocking test from running for the platform

Errors:

2021-07-07T13:22:11.2013515Z Building step 'Creating test overlay' via "/__w/1/s/eng/common/msbuild.sh"  --warnAsError false /__w/1/s/src/tests/run.proj /p:RestoreDefaultOptimizationDataPackage=false /p:PortableBuild=true /p:UsePartialNGENOptimization=false /maxcpucount "/flp:Verbosity=normal;LogFile=/__w/1/s/artifacts/log/Tests_Overlay_Managed.Linux.arm.Checked.log" "/flp1:WarningsOnly;LogFile=/__w/1/s/artifacts/log/Tests_Overlay_Managed.Linux.arm.Checked.wrn" "/flp2:ErrorsOnly;LogFile=/__w/1/s/artifacts/log/Tests_Overlay_Managed.Linux.arm.Checked.err" /t:CreateTestOverlay /p:TargetArchitecture=arm /p:Configuration=Checked /p:TargetOS=Linux /nodeReuse:false     /p:CLRTestPriorityToBuild=1 /p:LibrariesConfiguration=Release /p:CrossBuild=true
2021-07-07T13:22:12.5283318Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies_fs/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies_fs/test_dependencies.fsproj]
2021-07-07T13:22:12.5695748Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies/test_dependencies.csproj]
2021-07-07T13:22:12.5760866Z 
2021-07-07T13:22:12.5761731Z Build FAILED.
2021-07-07T13:22:12.5762107Z 
2021-07-07T13:22:12.5764946Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies_fs/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies_fs/test_dependencies.fsproj]
2021-07-07T13:22:12.5768828Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies/test_dependencies.csproj]
2021-07-07T13:22:12.5770626Z     0 Warning(s)

Sample build:
https://dev.azure.com/dnceng/public/_build/results?buildId=1223859&view=logs&j=22eeac8c-742e-5aad-c88c-3907a882a5f0&t=69ea8ee9-214f-5151-238f-f6b650cbf6ad&l=62

Introduced by #54914

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[kunalspathak]

@ViktorHofer

Tagging subscribers to this area: @hoyosjs
See info in area-owners.md if you want to be subscribed.

Issue Details

---

The outerloop CI is failing on Linux_musl arm/arm64 while generating CORE_ROOT blocking test from running for the platform

Errors:

2021-07-07T13:22:11.2013515Z Building step 'Creating test overlay' via "/__w/1/s/eng/common/msbuild.sh"  --warnAsError false /__w/1/s/src/tests/run.proj /p:RestoreDefaultOptimizationDataPackage=false /p:PortableBuild=true /p:UsePartialNGENOptimization=false /maxcpucount "/flp:Verbosity=normal;LogFile=/__w/1/s/artifacts/log/Tests_Overlay_Managed.Linux.arm.Checked.log" "/flp1:WarningsOnly;LogFile=/__w/1/s/artifacts/log/Tests_Overlay_Managed.Linux.arm.Checked.wrn" "/flp2:ErrorsOnly;LogFile=/__w/1/s/artifacts/log/Tests_Overlay_Managed.Linux.arm.Checked.err" /t:CreateTestOverlay /p:TargetArchitecture=arm /p:Configuration=Checked /p:TargetOS=Linux /nodeReuse:false     /p:CLRTestPriorityToBuild=1 /p:LibrariesConfiguration=Release /p:CrossBuild=true
2021-07-07T13:22:12.5283318Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies_fs/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies_fs/test_dependencies.fsproj]
2021-07-07T13:22:12.5695748Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies/test_dependencies.csproj]
2021-07-07T13:22:12.5760866Z 
2021-07-07T13:22:12.5761731Z Build FAILED.
2021-07-07T13:22:12.5762107Z 
2021-07-07T13:22:12.5764946Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies_fs/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies_fs/test_dependencies.fsproj]
2021-07-07T13:22:12.5768828Z /__w/1/s/.dotnet/sdk/6.0.100-preview.4.21255.9/Sdks/Microsoft.NET.Sdk/targets/Microsoft.PackageDependencyResolution.targets(241,5): error NETSDK1047: Assets file '/__w/1/s/artifacts/tests/coreclr/packages/Common/test_dependencies/test_dependencies/project.assets.json' doesn't have a target for 'net6.0/linux-arm'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project. You may also need to include 'linux-arm' in your project's RuntimeIdentifiers. [/__w/1/s/src/tests/Common/test_dependencies/test_dependencies.csproj]
2021-07-07T13:22:12.5770626Z     0 Warning(s)

Sample build:
https://dev.azure.com/dnceng/public/_build/results?buildId=1223859&view=logs&j=22eeac8c-742e-5aad-c88c-3907a882a5f0&t=69ea8ee9-214f-5151-238f-f6b650cbf6ad&l=62

Introduced by #54914

Author:	kunalspathak
Assignees:	-
Labels:	area-Infrastructure-coreclr, blocking-clean-ci-optional, ci-health, untriaged
Milestone:	-

[hoyosjs]

This feels like fallout of our weird way of creating the core_root

cc: @JulieLeeMSFT this is what you'd reported in the infra channel. Sorry we missed this.

[ViktorHofer]

from @echesakovMSFT:

This seems to be broken since 566b53a - linux-musl-arm and linux-musl-arm64 CORE_ROOT generation was working in runtime-coreclr outerloop #20210706.1 and failed in runtime-coreclr outerloop #20210706.2 for the first time (and has been red since then).
@ViktorHofer Can you please take a look at this?
cc @dotnet/jit-contrib @dotnet/runtime-infrastructure

cc @am11 as well. Will take a look when I get to it. Can't promise if it will be this week.