42 lines
1.1 KiB
Plaintext
42 lines
1.1 KiB
Plaintext
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=================
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VMCoreInfo device
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=================
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The `-device vmcoreinfo` will create a fw_cfg entry for a guest to
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store dump details.
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etc/vmcoreinfo
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**************
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A guest may use this fw_cfg entry to add information details to qemu
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dumps.
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The entry of 16 bytes has the following layout, in little-endian::
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#define VMCOREINFO_FORMAT_NONE 0x0
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#define VMCOREINFO_FORMAT_ELF 0x1
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struct FWCfgVMCoreInfo {
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uint16_t host_format; /* formats host supports */
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uint16_t guest_format; /* format guest supplies */
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uint32_t size; /* size of vmcoreinfo region */
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uint64_t paddr; /* physical address of vmcoreinfo region */
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};
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Only full write (of 16 bytes) are considered valid for further
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processing of entry values.
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A write of 0 in guest_format will disable further processing of
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vmcoreinfo entry values & content.
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Format & content
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****************
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As of qemu 2.11, only VMCOREINFO_FORMAT_ELF is supported.
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The entry gives location and size of an ELF note that is appended in
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qemu dumps.
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The note format/class must be of the target bitness and the size must
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be less than 1Mb.
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