Commit 331282fd authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: SVM: Drop 32-bit "support" from __svm_sev_es_vcpu_run() 



Drop 32-bit "support" from __svm_sev_es_vcpu_run(), as SEV/SEV-ES firmly
64-bit only.  The "support" was purely the result of bad copy+paste from
__svm_vcpu_run(), which in turn was slightly less bad copy+paste from
__vmx_vcpu_run().

Opportunistically convert to unadulterated register accesses so that it's
easier (but still not easy) to follow which registers hold what arguments,
and when.

Reviewed-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240223204233.3337324-4-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 7774c8f3

arch/x86/kvm/svm/vmenter.S

+13 −31
Original line number Diff line number Diff line
@@ -298,17 +298,12 @@ SYM_FUNC_END(__svm_vcpu_run) 
 * @spec_ctrl_intercepted: bool

 */

SYM_FUNC_START(__svm_sev_es_vcpu_run)

	push %_ASM_BP

#ifdef CONFIG_X86_64

	push %rbp

	push %r15

	push %r14

	push %r13

	push %r12

#else

	push %edi

	push %esi

#endif

	push %_ASM_BX

	push %rbx



	/*

	 * Save variables needed after vmexit on the stack, in inverse
@@ -316,39 +311,31 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run) 
	 */



	/* Accessed directly from the stack in RESTORE_HOST_SPEC_CTRL.  */

	push %_ASM_ARG2

	push %rsi



	/* Save @svm. */

	push %_ASM_ARG1



.ifnc _ASM_ARG1, _ASM_DI

	/*

	 * Stash @svm in RDI early. On 32-bit, arguments are in RAX, RCX

	 * and RDX which are clobbered by RESTORE_GUEST_SPEC_CTRL.

	 */

	mov %_ASM_ARG1, %_ASM_DI

.endif

	push %rdi



	/* Clobbers RAX, RCX, RDX.  */

	RESTORE_GUEST_SPEC_CTRL



	/* Get svm->current_vmcb->pa into RAX. */

	mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX

	mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX

	mov SVM_current_vmcb(%rdi), %rax

	mov KVM_VMCB_pa(%rax), %rax



	/* Enter guest mode */

	sti



1:	vmrun %_ASM_AX

1:	vmrun %rax



2:	cli



	/* Pop @svm to RDI, guest registers have been saved already. */

	pop %_ASM_DI

	pop %rdi



#ifdef CONFIG_MITIGATION_RETPOLINE

	/* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */

	FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE

	FILL_RETURN_BUFFER %rax, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE

#endif



	/* Clobbers RAX, RCX, RDX.  */
@@ -364,26 +351,21 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run) 
	UNTRAIN_RET_VM



	/* "Pop" @spec_ctrl_intercepted.  */

	pop %_ASM_BX

	pop %rbx



	pop %_ASM_BX

	pop %rbx



#ifdef CONFIG_X86_64

	pop %r12

	pop %r13

	pop %r14

	pop %r15

#else

	pop %esi

	pop %edi

#endif

	pop %_ASM_BP

	pop %rbp

	RET



	RESTORE_GUEST_SPEC_CTRL_BODY

	RESTORE_HOST_SPEC_CTRL_BODY



3:	cmpb $0, _ASM_RIP(kvm_rebooting)

3:	cmpb $0, kvm_rebooting(%rip)

	jne 2b

	ud2