193a7bfb69
Summary: Not all minidumps contain information about memory permissions. However, it is still important to know which regions of memory contain potentially executable code. This is particularly important for unwinding on win32, as the default unwind method there relies on scanning the stack for things which "look like" code pointers. This patch enables ProcessMinidump to reconstruct the likely permissions of memory regions using the sections of loaded object files. It only does this if we don't have a better source (memory info list stream, or linux /proc/maps) for this information, and only if the information in the object files does not conflict with the information in the minidump. Theoretically that last bit could be improved, since the permissions obtained from the MemoryList streams is also only a very rough guess, but it did not seem worthwhile to complicate the implementation because of that because there will generally be no overlap in practice as the MemoryList will contain the stack contents and not any module data. The patch adds a test checking that the module section permissions are entered into the memory region list, and also a test which demonstrate that now the unwinder is able to correctly find return addresses even in minidumps without memory info list streams. There's one TODO left in this patch, which is that the "memory region" output does not give any indication about the "don't know" values of memory region permissions (it just prints them as if they permission bit was set). I address this in a follow up. Reviewers: amccarth, clayborg Subscribers: mgrang, lldb-commits Differential Revision: https://reviews.llvm.org/D69105
41 lines
1.1 KiB
YAML
41 lines
1.1 KiB
YAML
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