linux-kernel - [PATCH 04/30] KVM: nSVM: remove exit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 29 May 2020 11:39:08 -0400
From:   Paolo Bonzini <pbonzini@...hat.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Subject: [PATCH 04/30] KVM: nSVM: remove exit_required

All events now inject vmexits before vmentry rather than after vmexit.  Therefore,
exit_required is not set anymore and we can remove it.

Signed-off-by: Paolo Bonzini <pbonzini@...hat.com>
---
 arch/x86/kvm/svm/nested.c |  3 +--
 arch/x86/kvm/svm/svm.c    | 14 --------------
 arch/x86/kvm/svm/svm.h    |  3 ---
 3 files changed, 1 insertion(+), 19 deletions(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 1ae13fd17028..3d17c62a84a3 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -792,8 +792,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
 	bool block_nested_events =
-		kvm_event_needs_reinjection(vcpu) || svm->nested.exit_required ||
-		svm->nested.nested_run_pending;
+		kvm_event_needs_reinjection(vcpu) || svm->nested.nested_run_pending;
 
 	if (vcpu->arch.exception.pending) {
 		if (block_nested_events)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 89b6fb1e0abc..545f63ebc720 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2889,13 +2889,6 @@ static int handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath)
 	if (npt_enabled)
 		vcpu->arch.cr3 = svm->vmcb->save.cr3;
 
-	if (unlikely(svm->nested.exit_required)) {
-		nested_svm_vmexit(svm);
-		svm->nested.exit_required = false;
-
-		return 1;
-	}
-
 	if (is_guest_mode(vcpu)) {
 		int vmexit;
 
@@ -3327,13 +3320,6 @@ static fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
 	svm->vmcb->save.rsp = vcpu->arch.regs[VCPU_REGS_RSP];
 	svm->vmcb->save.rip = vcpu->arch.regs[VCPU_REGS_RIP];
 
-	/*
-	 * A vmexit emulation is required before the vcpu can be executed
-	 * again.
-	 */
-	if (unlikely(svm->nested.exit_required))
-		return EXIT_FASTPATH_NONE;
-
 	/*
 	 * Disable singlestep if we're injecting an interrupt/exception.
 	 * We don't want our modified rflags to be pushed on the stack where
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 8342032291fc..89fab75dd4f5 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -95,9 +95,6 @@ struct nested_state {
 	u64 vmcb_msrpm;
 	u64 vmcb_iopm;
 
-	/* A VMEXIT is required but not yet emulated */
-	bool exit_required;
-
 	/* A VMRUN has started but has not yet been performed, so
 	 * we cannot inject a nested vmexit yet.  */
 	bool nested_run_pending;
-- 
2.26.2