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author | Paolo Bonzini <pbonzini@redhat.com> | 2022-11-07 04:17:29 -0500 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-11-09 12:16:57 -0500 |
commit | f6d58266d731fd7e63163790aad21e0dbb1d5264 (patch) | |
tree | 21c99f0827c7ef76afc339aaba57551e4cfd4a07 /arch/x86/kvm/svm/vmenter.S | |
parent | f7ef280132f9bf6f82acf5aa5c3c837206eef501 (diff) | |
download | lwn-f6d58266d731fd7e63163790aad21e0dbb1d5264.tar.gz lwn-f6d58266d731fd7e63163790aad21e0dbb1d5264.zip |
KVM: SVM: retrieve VMCB from assembly
Continue moving accesses to struct vcpu_svm to vmenter.S. Reducing the
number of arguments limits the chance of mistakes due to different
registers used for argument passing in 32- and 64-bit ABIs; pushing the
VMCB argument and almost immediately popping it into a different
register looks pretty weird.
32-bit ABI is not a concern for __svm_sev_es_vcpu_run() which is 64-bit
only; however, it will soon need @svm to save/restore SPEC_CTRL so stay
consistent with __svm_vcpu_run() and let them share the same prototype.
No functional change intended.
Cc: stable@vger.kernel.org
Fixes: a149180fbcf3 ("x86: Add magic AMD return-thunk")
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/svm/vmenter.S')
-rw-r--r-- | arch/x86/kvm/svm/vmenter.S | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S index 531510ab6072..d07bac1952c5 100644 --- a/arch/x86/kvm/svm/vmenter.S +++ b/arch/x86/kvm/svm/vmenter.S @@ -32,7 +32,6 @@ /** * __svm_vcpu_run - Run a vCPU via a transition to SVM guest mode - * @vmcb_pa: unsigned long * @svm: struct vcpu_svm * */ SYM_FUNC_START(__svm_vcpu_run) @@ -49,16 +48,16 @@ SYM_FUNC_START(__svm_vcpu_run) push %_ASM_BX /* Save @svm. */ - push %_ASM_ARG2 - - /* Save @vmcb. */ push %_ASM_ARG1 +.ifnc _ASM_ARG1, _ASM_DI /* Move @svm to RDI. */ - mov %_ASM_ARG2, %_ASM_DI + mov %_ASM_ARG1, %_ASM_DI +.endif - /* "POP" @vmcb to RAX. */ - pop %_ASM_AX + /* Get svm->current_vmcb->pa into RAX. */ + mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX + mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX /* Load guest registers. */ mov VCPU_RCX(%_ASM_DI), %_ASM_CX @@ -170,7 +169,7 @@ SYM_FUNC_END(__svm_vcpu_run) /** * __svm_sev_es_vcpu_run - Run a SEV-ES vCPU via a transition to SVM guest mode - * @vmcb_pa: unsigned long + * @svm: struct vcpu_svm * */ SYM_FUNC_START(__svm_sev_es_vcpu_run) push %_ASM_BP @@ -185,8 +184,9 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run) #endif push %_ASM_BX - /* Move @vmcb to RAX. */ - mov %_ASM_ARG1, %_ASM_AX + /* Get svm->current_vmcb->pa into RAX. */ + mov SVM_current_vmcb(%_ASM_ARG1), %_ASM_AX + mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX /* Enter guest mode */ sti |