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…e to bool Make kpatch_line_macro_change_only()'s usage more clear by changing its return type to bool. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
sm00th
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Approving given this PR contains a commit updating unit-test objectfiles submodule pointer.
CONFIG_PRINTK_INDEX creates a static local struct variable named `_entry` for every call site to printk(). The initializer for that struct assigns the `__LINE__` macro to one of its fields. Similarly to the WARN macro's usage [1] of `__LINE__`, it causes problems because it results in the line number getting directly embedded in the struct. If a line is added or removed higher up in the source file, the `_entry` struct changes accordingly due to a change in the printk() call site line number. `_entry` is similar to other "special" static locals, in that we don't need to correlate the patched version with the original version. We can instead just ignore any changes to it. Any substantial (non-line-number) change to the `_entry` struct would be a second-order (dependent) effect of a first-order code change, which would be detected using other means. In that case the patched version of `_entry` will be included, due to being referenced by the changed function. Fixes: dynup#1206 [1] See kpatch_line_macro_change_only() Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
For each printk() call site, CONFIG_PRINTK_INDEX makes a static local struct named `_entry`, and then adds a pointer to it in the `.printk_index` section. When regenerating the `.printk_index` section for the patch module, we only need to include those entries which are referenced by included functions. Luckily this is a common pattern already used by several other "special" sections. Add `.printk_index` to the special section handling logic. Fixes: dynup#1206 Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
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v2: add unit test reference |
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It works great in my tests. Thanks! |
liu-song-6
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Aug 14, 2021
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As described in #1206. See the commit messages for more info. Will post unit tests momentarily.