KVM: x86: Convert vcpu_run()'s immediate exit param into a generic bitmap

[ Upstream commit 2478b1b220c49d25cb1c3f061ec4f9b351d9a131 ]

Convert kvm_x86_ops.vcpu_run()'s "force_immediate_exit" boolean parameter
into an a generic bitmap so that similar "take action" information can be
passed to vendor code without creating a pile of boolean parameters.

This will allow dropping kvm_x86_ops.set_dr6() in favor of a new flag, and
will also allow for adding similar functionality for re-loading debugctl
in the active VMCS.

Opportunistically massage the TDX WARN and comment to prepare for adding
more run_flags, all of which are expected to be mutually exclusive with
TDX, i.e. should be WARNed on.

No functional change intended.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250610232010.162191-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
[sean: drop TDX crud, account for lack of kvm_x86_call()]
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 86f3bd6601e7a07e1132bf27518649b89444a67a..1383f5e5238a15fdccecbe99f81333e3b2033b72 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1456,6 +1456,10 @@ static inline u16 kvm_lapic_irq_dest_mode(bool dest_mode_logical)
        return dest_mode_logical ? APIC_DEST_LOGICAL : APIC_DEST_PHYSICAL;
 }
 
+enum kvm_x86_run_flags {
+       KVM_RUN_FORCE_IMMEDIATE_EXIT    = BIT(0),
+};
+
 struct kvm_x86_ops {
        const char *name;
 
@@ -1529,7 +1533,7 @@ struct kvm_x86_ops {
 
        int (*vcpu_pre_run)(struct kvm_vcpu *vcpu);
        enum exit_fastpath_completion (*vcpu_run)(struct kvm_vcpu *vcpu,
-                                                 bool force_immediate_exit);
+                                                 u64 run_flags);
        int (*handle_exit)(struct kvm_vcpu *vcpu,
                enum exit_fastpath_completion exit_fastpath);
        int (*skip_emulated_instruction)(struct kvm_vcpu *vcpu);

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 12de50db401ffe5816a8d3ec0e5e7751e403c60b..dc8a1b72d8ec8b49cf4a17a4cf68d7624927c578 100644 (file)
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4008,9 +4008,9 @@ static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu, bool spec_ctrl_in
        guest_state_exit_irqoff();
 }
 
-static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu,
-                                         bool force_immediate_exit)
+static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags)
 {
+       bool force_immediate_exit = run_flags & KVM_RUN_FORCE_IMMEDIATE_EXIT;
        struct vcpu_svm *svm = to_svm(vcpu);
        bool spec_ctrl_intercepted = msr_write_intercepted(vcpu, MSR_IA32_SPEC_CTRL);
 

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 179747d04edcc90628e25194eecfe5fd2fbeb4b2..382f4220068811810743af13c28a6d506a1a74c7 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7204,8 +7204,9 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
        guest_state_exit_irqoff();
 }
 
-static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, bool force_immediate_exit)
+static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu, u64 run_flags)
 {
+       bool force_immediate_exit = run_flags & KVM_RUN_FORCE_IMMEDIATE_EXIT;
        struct vcpu_vmx *vmx = to_vmx(vcpu);
        unsigned long cr3, cr4;
 

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 400a6e9fb0be2ce2ed7fe98906901ab411345594..83e5e823cbae8e990f1f0c36c47bf10930a27f99 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10591,6 +10591,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                dm_request_for_irq_injection(vcpu) &&
                kvm_cpu_accept_dm_intr(vcpu);
        fastpath_t exit_fastpath;
+       u64 run_flags;
 
        bool req_immediate_exit = false;
 
@@ -10811,8 +10812,11 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                goto cancel_injection;
        }
 
-       if (req_immediate_exit)
+       run_flags = 0;
+       if (req_immediate_exit) {
+               run_flags |= KVM_RUN_FORCE_IMMEDIATE_EXIT;
                kvm_make_request(KVM_REQ_EVENT, vcpu);
+       }
 
        fpregs_assert_state_consistent();
        if (test_thread_flag(TIF_NEED_FPU_LOAD))
@@ -10848,7 +10852,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                WARN_ON_ONCE((kvm_vcpu_apicv_activated(vcpu) != kvm_vcpu_apicv_active(vcpu)) &&
                             (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED));
 
-               exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu, req_immediate_exit);
+               exit_fastpath = static_call(kvm_x86_vcpu_run)(vcpu, run_flags);
                if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
                        break;
 
@@ -10860,6 +10864,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                        break;
                }
 
+               run_flags = 0;
+
                /* Note, VM-Exits that go down the "slow" path are accounted below. */
                ++vcpu->stat.exits;
        }