Missing log "pushing layers" and "pushing manifest for"

[ur4t]

Contributing guidelines and issue reporting guide

• I've read the contributing guidelines and wholeheartedly agree. I've also read the issue reporting guide.

Well-formed report checklist

• I have found a bug that the documentation does not mention anything about my problem
• I have found a bug that there are no open or closed issues that are related to my problem
• I have provided version/information about my environment and done my best to provide a reproducer

Description of bug

Bug description

buildkitd v0.28.0 does not print pushing logs. It might be caused by 88ef66c.

Reproduction

FROM scratch AS base
COPY --link <<-EOF hello
hello
EOF

buildctl build --progress plain --frontend dockerfile.v0 --local dockerfile=. --local context=. --output type=image,name=registry.me/library/hello:v0.0.1,push=true

buildkitd v0.27.0 + buildctl v0.27.0:

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 93B done
#1 DONE 0.0s

#2 [internal] load .dockerignore
#2 transferring context: 2B done
#2 DONE 0.0s

#3 [internal] preparing inline document
#3 DONE 0.0s

#4 exporting to image
#4 exporting layers done
#4 exporting manifest sha256:xxxxx done
#4 exporting config sha256:xxxxx done
#4 pushing layers
#4 ...

#5 [auth] library/hello:pull,push token for registry.me
#5 DONE 0.0s

#4 exporting to image
#4 pushing layers 1.4s done
#4 pushing manifest for registry.me/library/hello:v0.0.1@sha256:xxxxx
#4 pushing manifest for registry.me/library/hello:v0.0.1@sha256:xxxxx 0.2s done
#4 DONE 1.6s

buildkitd v0.28.0 + buildctl v0.28.0/v0.27.0:

#1 [internal] load build definition from Dockerfile
#1 transferring dockerfile: 93B done
#1 DONE 0.0s

#2 [internal] load .dockerignore
#2 transferring context: 2B done
#2 DONE 0.0s

#3 [internal] preparing inline document
#3 DONE 0.0s

#4 exporting to image
#4 exporting layers done
#4 exporting manifest sha256:xxxxx done
#4 exporting config sha256:xxxxx done
#4 DONE 0.0s

#5 [auth] library/hello:pull,push token for registry.me
#5 DONE 0.0s

Version information

buildkitd github.com/moby/buildkit v0.28.0 5245d869d85d9c98f986b600584c332a3b001986
buildctl github.com/moby/buildkit v0.28.0 5245d869d85d9c98f986b600584c332a3b001986
buildctl github.com/moby/buildkit v0.27.0 2bcd66daa720bd45da2a43db59cd3e8ddf3f39ae

[tonistiigi]

This has been fixed by #6587