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| author | Catalin Marinas <catalin.marinas@arm.com> | 2022-01-31 17:54:56 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-02-15 23:53:29 +0100 |
| commit | 731451ab3c0c6fe88142dbc73a74c71bd92a5cff (patch) | |
| tree | 8ea0a4475e8fb0f751c8fc2d0920771bd527e4b5 /Documentation/arm64 | |
| parent | arm64: mte: Dump the MTE tags in the core file (diff) | |
| download | linux-731451ab3c0c6fe88142dbc73a74c71bd92a5cff.tar.xz linux-731451ab3c0c6fe88142dbc73a74c71bd92a5cff.zip | |
arm64: mte: Document the core dump file format
Add the program header definition and data layout for the
PT_ARM_MEMTAG_MTE segments.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Luis Machado <luis.machado@linaro.org>
Link: https://lore.kernel.org/r/20220131165456.2160675-6-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'Documentation/arm64')
| -rw-r--r-- | Documentation/arm64/memory-tagging-extension.rst | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/Documentation/arm64/memory-tagging-extension.rst b/Documentation/arm64/memory-tagging-extension.rst index 7b99c8f428eb..5a70d7a3ca12 100644 --- a/Documentation/arm64/memory-tagging-extension.rst +++ b/Documentation/arm64/memory-tagging-extension.rst @@ -213,6 +213,29 @@ address ABI control and MTE configuration of a process as per the Documentation/arm64/tagged-address-abi.rst and above. The corresponding ``regset`` is 1 element of 8 bytes (``sizeof(long))``). +Core dump support +----------------- + +The allocation tags for user memory mapped with ``PROT_MTE`` are dumped +in the core file as additional ``PT_ARM_MEMTAG_MTE`` segments. The +program header for such segment is defined as: + +:``p_type``: ``PT_ARM_MEMTAG_MTE`` +:``p_flags``: 0 +:``p_offset``: segment file offset +:``p_vaddr``: segment virtual address, same as the corresponding + ``PT_LOAD`` segment +:``p_paddr``: 0 +:``p_filesz``: segment size in file, calculated as ``p_mem_sz / 32`` + (two 4-bit tags cover 32 bytes of memory) +:``p_memsz``: segment size in memory, same as the corresponding + ``PT_LOAD`` segment +:``p_align``: 0 + +The tags are stored in the core file at ``p_offset`` as two 4-bit tags +in a byte. With the tag granule of 16 bytes, a 4K page requires 128 +bytes in the core file. + Example of correct usage ======================== |