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chore(doc): remove arm64 snapshot reg length limitation #5094

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Mar 18, 2025
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chore(doc): remove arm64 snapshot reg length limitation #5094

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11 changes: 0 additions & 11 deletions docs/snapshotting/snapshot-support.md
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Expand Up @@ -126,17 +126,6 @@ The snapshot functionality is still in developer preview due to the following:

### Limitations

- Currently on aarch64 platforms only lower 128 bits of any register are saved
due to the limitations of `get/set_one_reg` from `kvm-ioctls` crate that
Firecracker uses to interact with KVM. This creates an issue with newer
aarch64 CPUs with support for registers with width greater than 128 bits,
because these registers will be truncated before being stored in the snapshot.
This can lead to uVM failure if restored from such snapshot. Because registers
wider than 128 bits are usually used in SVE instructions, the best way to
mitigate this issue is to ensure that the software run in uVM does not use SVE
instructions during snapshot creation. An alternative way is to use
[CPU templates](../cpu_templates/cpu-templates.md) to disable SVE related
features in uVM.
- High snapshot latency on 5.4+ host kernels due to cgroups V1. We strongly
recommend to deploy snapshots on cgroups V2 enabled hosts for the implied
kernel versions -
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