qemu: reduce monitor socket path #13971
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.changelog/13971.txt
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| ```release-note:improvement | ||
| qemu: restore the monitor socket path when restoring a QEMU task. | ||
| ``` |
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Should we note this as a bug fix? Technically the behavior is different now even for existing tasks.
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Hum...good question. I think then I will split this into two PRs: one for the bug fix where the socket path was not being restored (and will be backported) and another for reducing the socket name and improving the error message (not backported).
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#14000 handles the bug fix. I will rebase this branch with socket renaming once that one is merged.
The QEMU driver can take an optional `graceful_shutdown` configuration which will create a Unix socket to send ACPI shutdown signal to the VM. Unix sockets have a hard length limit and the driver implementation assumed that QEMU versions 2.10.1 were able to handle longer paths. This is not correct, the linked QEMU fix only changed the behaviour from silently truncating longer socket paths to throwing an error. By validating the socket path before starting the QEMU machine we can provide users a more actionable and meaningful error message, and by using a shorter socket file name we leave a bit more room for user-defined values in the path, such as the task name. The maximum length allowed is also platform-dependant, so validation needs to be different for each OS.
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I'm going to lock this pull request because it has been closed for 120 days ⏳. This helps our maintainers find and focus on the active contributions. |
The QEMU driver can take an optional
graceful_shutdownconfigurationwhich will create a Unix socket to send ACPI shutdown signal to the VM.
Unix sockets have a hard length limit and the driver implementation
assumed that QEMU versions 2.10.1 were able to handle longer paths. This
is not correct, the linked QEMU fix only changed the behaviour from
silently truncating longer socket paths to throwing an error.
By validating the socket path before starting the QEMU machine we can
provide users a more actionable and meaningful error message, and by
using a shorter socket file name we leave a bit more room for
user-defined values in the path, such as the task name.
The maximum length allowed is also platform-dependant, so validation
needs to be different for each OS.