stage1: add TD Partitioning support #397
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
msft-jlange
approved these changes
Jul 1, 2024
Since stage1.lds always designates to_pm_mode to 0xfffffe00, there is no need to use relative addressing from 0xfffffe00. Use the symbol's absolute address directly instead, when possible, to simplify reset.S. Signed-off-by: Peter Fang <[email protected]>
TD CPUs always start execution in protected (32-bit) non-paged mode at the reset vector. Add the code necessary for a vCPU to run in the resetvector section directly in 32-bit mode. Since there is no need for a TD CPU to transition to 32-bit mode, it takes a slightly simpler path to reach startup_32. TD CPUs are initialized with a flat 32-bit code segment so absolute addressing can be used. Signed-off-by: Peter Fang <[email protected]>
Since TDP is the only platform right now that uses stage1-trampoline, only allow platform type TDP when in trampoline-only mode. All TD vCPUs start execution in 32-bit mode concurrently and therefore only TD BSP is allowed to use the stage2 stack. Set vtom in Stage2LaunchInfo based on the initial value of %ebx (GPAW). Program an invalid address (0x7ffff000) into a TD AP's ESP register. This address is chosen because a) it is most likely not an MMIO address and b) it is an unaccepted page if it's backed by memory. Signed-off-by: Peter Fang <[email protected]>
peterfang
force-pushed
the
dev-tdp-stage1
branch
from
465bce0
to
dde07ca
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This set of patches enables TDX in stage1 trampoline-only mode. This includes bootstrapping from the reset vector in protected non-paged mode, performing sanity checks, and setting up the ESP register.