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@@ -429,30 +429,6 @@ See Documentation/ABI/testing/sysfs-kernel-livepatch for more details.
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The current Livepatch implementation has several limitations:
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- + The patch must not change the semantic of the patched functions.
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-
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- The current implementation guarantees only that either the old
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- or the new function is called. The functions are patched one
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- by one. It means that the patch must _not_ change the semantic
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- of the function.
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- + Data structures can not be patched.
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-
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- There is no support to version data structures or anyhow migrate
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- one structure into another. Also the simple consistency model does
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- not allow to switch more functions atomically.
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-
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- Once there is more complex consistency mode, it will be possible to
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- use some workarounds. For example, it will be possible to use a hole
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- for a new member because the data structure is aligned. Or it will
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- be possible to use an existing member for something else.
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- There are no plans to add more generic support for modified structures
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- at the moment.
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+ Only functions that can be traced could be patched.
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Livepatch is based on the dynamic ftrace. In particular, functions
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