Support resizing output image #4133
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behrmann
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Jan 23, 2026
| if context.config.output_size and context.config.output_format == OutputFormat.disk: | ||
| output = context.staging / context.config.output_with_format | ||
| current_size = output.stat().st_size | ||
| if context.config.output_size > current_size: |
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Looking at the implementation, it is clear, that this can only grow the image, and the documentation does mention it, but logging warning in the case we cannot grow the image, would be a nicer UX.
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Thanks, like that with log_notice?
behrmann
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Jan 28, 2026
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LGTM. Can you rebase for CI to run?
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When the final image does not contain the rootfs it must be grown before being able to boot it. Since the exact size to grow is not easily known to the user, it's best if the image is already grown to the right size. Also, when flashing to disk it helps to have the image be the minimum size needed because otherwise flashing on a too small disk succeeds but boot will fail. With the right image size it's easier for the user to know whether the disk is large enough.
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When the final image does not contain the rootfs it must be grown before being able to boot it. Since the exact size to grow is not easily known to the user, it's best if the image is already grown to the right size. Also, when flashing to disk it helps to have the image be the minimum size needed because otherwise flashing on a too small disk succeeds but boot will fail. With the right image size it's easier for the user to know whether the disk is large enough.