From: Lai Jiangshan <jiangshan.ljs@antgroup.com>

The @root_hpa for kvm_mmu_invalidate_gva() is called with @mmu->root.hpa
or INVALID_PAGE where @mmu->root.hpa is to invalidate gva for the current
root (the same meaning as KVM_MMU_ROOT_CURRENT) and INVALID_PAGE is to
invalidate gva for all roots (the same meaning as KVM_MMU_ROOTS_ALL).

Change the argument type of kvm_mmu_invalidate_gva() and use
KVM_MMU_ROOT_XXX instead so that we can reuse the function for
kvm_mmu_invpcid_gva() and nested_ept_invalidate_addr() for invalidating
gva for different set of roots.

No fuctionalities changed.

Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
---
 arch/x86/include/asm/kvm_host.h |  2 +-
 arch/x86/kvm/mmu/mmu.c          | 39 +++++++++++++++++----------------
 arch/x86/kvm/x86.c              |  2 +-
 3 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4d2bc08794e4..81429a5640d6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2026,7 +2026,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
 		       void *insn, int insn_len);
 void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva);
 void kvm_mmu_invalidate_gva(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-			    gva_t gva, hpa_t root_hpa);
+			    gva_t gva, unsigned long roots);
 void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid);
 void kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd);
 
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index c91ee2927dd7..958e8eb977ed 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5707,10 +5707,12 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err
 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
 
 void kvm_mmu_invalidate_gva(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-			    gva_t gva, hpa_t root_hpa)
+			    gva_t gva, unsigned long roots)
 {
 	int i;
 
+	WARN_ON_ONCE(roots & ~KVM_MMU_ROOTS_ALL);
+
 	/* It's actually a GPA for vcpu->arch.guest_mmu.  */
 	if (mmu != &vcpu->arch.guest_mmu) {
 		/* INVLPG on a non-canonical address is a NOP according to the SDM.  */
@@ -5723,31 +5725,30 @@ void kvm_mmu_invalidate_gva(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 	if (!mmu->invlpg)
 		return;
 
-	if (root_hpa == INVALID_PAGE) {
+	if ((roots & KVM_MMU_ROOT_CURRENT) && VALID_PAGE(mmu->root.hpa))
 		mmu->invlpg(vcpu, gva, mmu->root.hpa);
 
-		/*
-		 * INVLPG is required to invalidate any global mappings for the VA,
-		 * irrespective of PCID. Since it would take us roughly similar amount
-		 * of work to determine whether any of the prev_root mappings of the VA
-		 * is marked global, or to just sync it blindly, so we might as well
-		 * just always sync it.
-		 *
-		 * Mappings not reachable via the current cr3 or the prev_roots will be
-		 * synced when switching to that cr3, so nothing needs to be done here
-		 * for them.
-		 */
-		for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
-			if (VALID_PAGE(mmu->prev_roots[i].hpa))
-				mmu->invlpg(vcpu, gva, mmu->prev_roots[i].hpa);
-	} else {
-		mmu->invlpg(vcpu, gva, root_hpa);
+	for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) {
+		if ((roots & KVM_MMU_ROOT_PREVIOUS(i)) &&
+		    VALID_PAGE(mmu->prev_roots[i].hpa))
+			mmu->invlpg(vcpu, gva, mmu->prev_roots[i].hpa);
 	}
 }
 
 void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
 {
-	kvm_mmu_invalidate_gva(vcpu, vcpu->arch.walk_mmu, gva, INVALID_PAGE);
+	/*
+	 * INVLPG is required to invalidate any global mappings for the VA,
+	 * irrespective of PCID. Since it would take us roughly similar amount
+	 * of work to determine whether any of the prev_root mappings of the VA
+	 * is marked global, or to just sync it blindly, so we might as well
+	 * just always sync it.
+	 *
+	 * Mappings not reachable via the current cr3 or the prev_roots will be
+	 * synced when switching to that cr3, so nothing needs to be done here
+	 * for them.
+	 */
+	kvm_mmu_invalidate_gva(vcpu, vcpu->arch.walk_mmu, gva, KVM_MMU_ROOTS_ALL);
 	++vcpu->stat.invlpg;
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 508074e47bc0..a81937a8fe0c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -799,7 +799,7 @@ void kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu,
 	if ((fault->error_code & PFERR_PRESENT_MASK) &&
 	    !(fault->error_code & PFERR_RSVD_MASK))
 		kvm_mmu_invalidate_gva(vcpu, fault_mmu, fault->address,
-				       fault_mmu->root.hpa);
+				       KVM_MMU_ROOT_CURRENT);
 
 	fault_mmu->inject_page_fault(vcpu, fault);
 }
-- 
2.19.1.6.gb485710b

On Tue, Feb 07, 2023, Lai Jiangshan wrote:
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index c91ee2927dd7..958e8eb977ed 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -5707,10 +5707,12 @@ int noinline kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 err
>  EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
>  
>  void kvm_mmu_invalidate_gva(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
> -			    gva_t gva, hpa_t root_hpa)
> +			    gva_t gva, unsigned long roots)
>  {
>  	int i;
>  
> +	WARN_ON_ONCE(roots & ~KVM_MMU_ROOTS_ALL);

This does nothing since KVM_MMU_ROOTS_ALL is ~0ul.  What I wanted is below, can
you slot that it?  Compile tested only.

--
From: Sean Christopherson <seanjc@google.com>
Date: Thu, 9 Feb 2023 16:37:43 -0800
Subject: [PATCH 2/8] KVM: x86/mmu: Sanity check input to kvm_mmu_free_roots()

Tweak KVM_MMU_ROOTS_ALL to precisely cover all current+previous root
flags, and add a sanity in kvm_mmu_free_roots() to verify that the set
of roots to free doesn't stray outside KVM_MMU_ROOTS_ALL.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/include/asm/kvm_host.h | 8 ++++----
 arch/x86/kvm/mmu/mmu.c          | 2 ++
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4d2bc08794e4..01d34f7d009d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -422,6 +422,10 @@ struct kvm_mmu_root_info {
 
 #define KVM_MMU_NUM_PREV_ROOTS 3
 
+#define KVM_MMU_ROOT_CURRENT		BIT(0)
+#define KVM_MMU_ROOT_PREVIOUS(i)	BIT(1+i)
+#define KVM_MMU_ROOTS_ALL		(BIT(1 + KVM_MMU_NUM_PREV_ROOTS) - 1)
+
 #define KVM_HAVE_MMU_RWLOCK
 
 struct kvm_mmu_page;
@@ -1978,10 +1982,6 @@ static inline int __kvm_irq_line_state(unsigned long *irq_state,
 	return !!(*irq_state);
 }
 
-#define KVM_MMU_ROOT_CURRENT		BIT(0)
-#define KVM_MMU_ROOT_PREVIOUS(i)	BIT(1+i)
-#define KVM_MMU_ROOTS_ALL		(~0UL)
-
 int kvm_pic_set_irq(struct kvm_pic *pic, int irq, int irq_source_id, int level);
 void kvm_pic_clear_all(struct kvm_pic *pic, int irq_source_id);
 
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index c91ee2927dd7..896abf9c1126 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3513,6 +3513,8 @@ void kvm_mmu_free_roots(struct kvm *kvm, struct kvm_mmu *mmu,
 	LIST_HEAD(invalid_list);
 	bool free_active_root;
 
+	WARN_ON_ONCE(roots_to_free & ~KVM_MMU_ROOTS_ALL);
+
 	BUILD_BUG_ON(KVM_MMU_NUM_PREV_ROOTS >= BITS_PER_LONG);
 
 	/* Before acquiring the MMU lock, see if we need to do any real work. */
--