Ensure that CONTEXT_XStateFeaturesMask is explicitly zeroed out on RtlCaptureContext #84012
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tannergooding
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Mar 28, 2023
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| LEAF_ENTRY RtlCaptureContext, _TEXT | ||
| mov DWORD PTR [rdi + CONTEXT_ContextFlags], (CONTEXT_AMD64 | CONTEXT_FULL | CONTEXT_SEGMENTS) | ||
| mov QWORD PTR [rdi + CONTEXT_XStateFeaturesMask], 0 | ||
| jmp C_FUNC(CONTEXT_CaptureContext) | ||
| LEAF_END RtlCaptureContext, _TEXT |
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Just something else to note...
It seems that CONTEXT_CaptureContext doesn't currently and, as far as I can tell, has never captured the YMM state. Is this expected? Should it be capturing that state as part of the thread suspend/restore logic here?
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Will address this question separately once I hear back from @janvorli
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@tannergooding the CONTEXT_CaptureContext is used only by the debugger code on Unix. It is not used for thread suspension. I am not sure if debugger stuff cares about the YMM registers or not.
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CC. @janvorli, @AndyAyersMS |
This was referenced Mar 28, 2023
AndyAyersMS
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Mar 28, 2023
ghost
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We don't explicitly zero the
CONTEXTstructs we create before callingRtlCaptureContextand so it leaves these bits otherwise undefined.This resolves the issue raised in #84000 (comment)
This resolves #84010