This repository has been archived by the owner on Jan 28, 2023. It is now read-only.
Fix incorrect VMX_ENTRY_CONTROLS loading. #225
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
wcwang
reviewed
Aug 7, 2019
core/vcpu.c
Outdated
| @@ -2015,18 +2015,11 @@ static void vmwrite_cr(struct vcpu_t *vcpu) | |||
| } | |||
|
|
|||
| if ((state->_cr4 & CR4_PAE) && (state->_cr0 & CR0_PG) && | |||
| (state->_cr0 & CR0_PE)) { | |||
| (state->_cr0 & CR0_PE)) | |||
There was a problem hiding this comment.
According to the coding style, conditional or loop statements with complex conditions or statements may be more readable with curly braces. Some projects require that an if must always have an accompanying brace.
There was a problem hiding this comment.
OK, I'll keep the curly braces.
There exists some issue when programming VMX_ENTRY_CONTROLS and GUEST_EFER: - ENTRY_CONTROL_LONG_MODE_GUEST has no chance to clear. - vmwrite_efer() called by vmwrite_cr() will check vmx field before vmx field gets updated, and itself will also program VMX_ENTRY_CONTROLS, which may cause incorrect VMX_ENTRY_CONTROLS programmed. - vmx filed entry_ctls_base and entry_ctls are loaded from vmcs in: vcpu_create()->vcpu_prepare()->fill_common_vmcs()->load_vmcs_common(). When vmwrite_cr() and vmwrite_efer() write a dirty VMX_ENTRY_CONTROLS, it only updates vmx field entry_ctls, but it compares with value of entry_ctls_base for dirty check, which may cause reduntant or miss programming to VMX_ENTRY_CONTROLS. Below changes are made: - Add the missing clear of ENTRY_CONTROL_LONG_MODE_GUEST. - Move vmwrite_efer() to last of vmwrite_cr() after VMX_ENTRY_CONTROLS programmed. - Remove unnecessary entry_ctls_base in vmx field. Signed-off-by: Colin Xu <[email protected]>
wcwang
approved these changes
Aug 16, 2019
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
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.
There exists some issue when programming VMX_ENTRY_CONTROLS and GUEST_EFER:
vmx field gets updated, and itself will also program VMX_ENTRY_CONTROLS,
which may cause incorrect VMX_ENTRY_CONTROLS programmed.
vcpu_create()->vcpu_prepare()->fill_common_vmcs()->load_vmcs_common().
When vmwrite_cr() and vmwrite_efer() write a dirty VMX_ENTRY_CONTROLS,
it only updates vmx field entry_ctls, but it compares with value of
entry_ctls_base for dirty check, which may cause reduntant or miss
programming to VMX_ENTRY_CONTROLS.
Below changes are made:
programmed.
Signed-off-by: Colin Xu [email protected]