Prevent some infinite recursion and loops - #352
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The motivation is to help stop AML causing a thread (or the system as a whole) to become deadlocked. The first protection adds a maximum method call stack depth. This has been chosen arbitrarily, for now. It does not protect against all possible ways of recursing infinitely. For example, it does not stop recursive table loads. (Although LoadTable is not currently supported) The second protection is a straightforward timeout for while loops, with associated tests. These are both based on the uACPI protections, although they differ in a key way: in uACPI, the method stack is unwound. If a table definition is reached, execution continues with the next statement, but the execution is still flagged as failed. In this crate, execution is stopped with an error.
martin-hughes
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Sep 14, 2026
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The actual tests are the same, but now the "shoulds" have become "musts".
martin-hughes
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Sep 14, 2026
| Panicked, | ||
| } | ||
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| impl<T> std::fmt::Debug for RunTestResult<T> |
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Needed to allow RunTestResult to be checked in assert_matches
martin-hughes
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Sep 14, 2026
| kind: BlockKind::Method { method_scope: scope.clone() }, | ||
| }; | ||
| let block = | ||
| Block { stream: code.clone(), pc: 0, kind: BlockKind::Method { method_scope: scope.clone() } }; |
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This is a pure formatting change - I'm not sure why the previous version was unacceptable to rustfmt. Maybe it's a new-nightly thing?
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Whoever merges this PR: it will interact with #345. The second of the two to be merged will need updating to handle the first. |
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The motivation is to help stop AML causing a thread (or the system as a whole) to become deadlocked.
The first protection adds a maximum method call stack depth. This has been chosen arbitrarily, for now. It does not protect against all possible ways of recursing infinitely. For example, it does not stop recursive table loads. (Although LoadTable is not currently supported)
The second protection is a straightforward timeout for while loops, with associated tests.
These are both based on the uACPI protections, although they differ in a key way: in uACPI, the method stack is unwound. If a table definition is reached, execution continues with the next statement, but the execution is still flagged as failed. In this crate, execution is stopped with an error.
Notes:
unwrap_methods, so I felt that was worth leaving for a separate PR.