runtime: include .data section in globals scan #2909
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This was referenced Jun 15, 2022
Previously we used to scan between _edata and _end. This is not correct: the .data section starts *before* _edata. Fixing this would mean changing _edata to _etext, but that didn't quite work either. It appears that there are inaccessible pages between _etext and _end on ARM. Therefore, a different solution was needed. What I've implemented is similar to Windows and MacOS: namely, finding writable segments by parsing the program header of the currently running program. It's a lot more verbose, but it should be correct on all architectures. It probably also reduces the globals to scan to those that _really_ need to be scanned. This bug didn't result in issues in CI, but did result in a bug in the recover branch: #2331. This patch fixes this bug.
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I hope I've really fixed it now. The new patch makes |
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All the globals are between _etext and _end. We were scanning only between _edata and _end, which mainly consists of the .bss section. Scanning from _etext ensures that the .data section is also included.
This bug didn't result in issues in CI, but did result in a bug in the recover branch: #2331. This patch fixes this bug.