[PATCH 0/7] KVM: Add a common API for range-based TLB invalidation

[PATCH 0/7] KVM: Add a common API for range-based TLB invalidation

[David Matlack]

This series introduces a common API for performing range-based TLB
invalidation. This is then used to supplant
kvm_arch_flush_remote_tlbs_memslot() and pave the way for two other
patch series:

1. https://lore.kernel.org/kvm/20230109215347.3119271-1-rananta@google.com/

  Adds ARM support for range-based TLB invalidation and needs a
  mechanism to invoke it from common code. This series provides such a
  mechanism via kvm_arch_flush_remote_tlbs_range().

2. https://lore.kernel.org/kvm/20221208193857.4090582-1-dmatlack@google.com/

  Refactors the TDP MMU into common code, which requires an API for
  range-based TLB invaliation.

This series is based on patches 29-33 from (2.), but I made some further
cleanups after looking at it a second time.

Tested on x86_64 and ARM64 using KVM selftests.

Cc: Raghavendra Rao Ananta <rananta@google.com>

David Matlack (7):
  KVM: Rename kvm_arch_flush_remote_tlb() to
    kvm_arch_flush_remote_tlbs()
  KVM: arm64: Use kvm_arch_flush_remote_tlbs()
  KVM: x86/mmu: Collapse kvm_flush_remote_tlbs_with_{range,address}()
    together
  KVM: x86/mmu: Rename kvm_flush_remote_tlbs_with_address()
  KVM: x86/MMU: Use gfn_t in kvm_flush_remote_tlbs_range()
  KVM: Allow range-based TLB invalidation from common code
  KVM: Move kvm_arch_flush_remote_tlbs_memslot() to common code

 arch/arm64/include/asm/kvm_host.h |  3 ++
 arch/arm64/kvm/Kconfig            |  1 -
 arch/arm64/kvm/arm.c              |  6 ---
 arch/arm64/kvm/mmu.c              |  6 +--
 arch/mips/include/asm/kvm_host.h  |  4 +-
 arch/mips/kvm/mips.c              | 12 ++----
 arch/riscv/kvm/mmu.c              |  6 ---
 arch/x86/include/asm/kvm_host.h   |  7 +++-
 arch/x86/kvm/mmu/mmu.c            | 68 ++++++++++---------------------
 arch/x86/kvm/mmu/mmu_internal.h   |  2 -
 arch/x86/kvm/mmu/paging_tmpl.h    |  4 +-
 arch/x86/kvm/mmu/tdp_mmu.c        |  7 ++--
 arch/x86/kvm/x86.c                |  2 +-
 include/linux/kvm_host.h          | 20 ++++++---
 virt/kvm/kvm_main.c               | 35 +++++++++++++---
 15 files changed, 87 insertions(+), 96 deletions(-)


base-commit: de60733246ff4545a0483140c1f21426b8d7cb7f
prerequisite-patch-id: 42a76ce7cec240776c21f674e99e893a3a6bee58
prerequisite-patch-id: c5ef6bbef252706b7e65b76dc9bd92cf320828f5
prerequisite-patch-id: c6e662cb6c369a47a027c25d3ccc7138a19b17f5
prerequisite-patch-id: 15a58bec64bf1537e6c9e2f52179fac652d441f7
prerequisite-patch-id: d5b6fea4724f4f2c3408b95d7ce5acdd4b528b10
-- 
2.39.0.246.g2a6d74b583-goog

[PATCH 1/7] KVM: Rename kvm_arch_flush_remote_tlb() to kvm_arch_flush_remote_tlbs()

[David Matlack]

Rename kvm_arch_flush_remote_tlb() and the associated macro
__KVM_HAVE_ARCH_FLUSH_REMOTE_TLB to kvm_arch_flush_remote_tlbs() and
__KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS respectively.

Making the name plural matches kvm_flush_remote_tlbs() and makes it more
clear that this function can affect more than one remote TLB.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/mips/include/asm/kvm_host.h | 4 ++--
 arch/mips/kvm/mips.c             | 2 +-
 arch/x86/include/asm/kvm_host.h  | 4 ++--
 include/linux/kvm_host.h         | 4 ++--
 virt/kvm/kvm_main.c              | 2 +-
 5 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 2803c9c21ef9..849eb482ad15 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -896,7 +896,7 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
 static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
 static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
 
-#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
-int kvm_arch_flush_remote_tlb(struct kvm *kvm);
+#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
+int kvm_arch_flush_remote_tlbs(struct kvm *kvm);
 
 #endif /* __MIPS_KVM_HOST_H__ */
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 36c8991b5d39..2e54e5fd8daa 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -981,7 +981,7 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 
 }
 
-int kvm_arch_flush_remote_tlb(struct kvm *kvm)
+int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 {
 	kvm_mips_callbacks->prepare_flush_shadow(kvm);
 	return 1;
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4d2bc08794e4..1bacc3de2432 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1789,8 +1789,8 @@ static inline struct kvm *kvm_arch_alloc_vm(void)
 #define __KVM_HAVE_ARCH_VM_FREE
 void kvm_arch_free_vm(struct kvm *kvm);
 
-#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
-static inline int kvm_arch_flush_remote_tlb(struct kvm *kvm)
+#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
+static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 {
 	if (kvm_x86_ops.tlb_remote_flush &&
 	    !static_call(kvm_x86_tlb_remote_flush)(kvm))
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 109b18e2789c..76711afe4d17 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1477,8 +1477,8 @@ static inline void kvm_arch_free_vm(struct kvm *kvm)
 }
 #endif
 
-#ifndef __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
-static inline int kvm_arch_flush_remote_tlb(struct kvm *kvm)
+#ifndef __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
+static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 {
 	return -ENOTSUPP;
 }
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d255964ec331..277507463678 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -363,7 +363,7 @@ void kvm_flush_remote_tlbs(struct kvm *kvm)
 	 * kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
 	 * barrier here.
 	 */
-	if (!kvm_arch_flush_remote_tlb(kvm)
+	if (!kvm_arch_flush_remote_tlbs(kvm)
 	    || kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 		++kvm->stat.generic.remote_tlb_flush;
 }
-- 
2.39.0.246.g2a6d74b583-goog

[PATCH 2/7] KVM: arm64: Use kvm_arch_flush_remote_tlbs()

[David Matlack]

Use kvm_arch_flush_remote_tlbs() instead of
CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL. The two mechanisms solve the same
problem, allowing architecture-specific code to provide a non-IPI
implementation of remote TLB flushing.

Dropping CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL allows KVM to standardize
all architectures on kvm_arch_flush_remote_tlbs() instead of maintaining
two mechanisms.

Opt to standardize on kvm_arch_flush_remote_tlbs() since it avoids
duplicating the generic TLB stats across architectures that implement
their own remote TLB flush.

This adds an extra function call to the ARM64 kvm_flush_remote_tlbs()
path, but (I assume) that is a small cost in comparison to flushing
remote TLBs.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/arm64/include/asm/kvm_host.h | 3 +++
 arch/arm64/kvm/Kconfig            | 1 -
 arch/arm64/kvm/mmu.c              | 6 +++---
 virt/kvm/kvm_main.c               | 2 --
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 113e20fdbb56..062800f1dc54 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -998,6 +998,9 @@ int __init kvm_set_ipa_limit(void);
 #define __KVM_HAVE_ARCH_VM_ALLOC
 struct kvm *kvm_arch_alloc_vm(void);
 
+#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS
+int kvm_arch_flush_remote_tlbs(struct kvm *kvm);
+
 static inline bool kvm_vm_is_protected(struct kvm *kvm)
 {
 	return false;
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index ca6eadeb7d1a..e9ac57098a0b 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -25,7 +25,6 @@ menuconfig KVM
 	select MMU_NOTIFIER
 	select PREEMPT_NOTIFIERS
 	select HAVE_KVM_CPU_RELAX_INTERCEPT
-	select HAVE_KVM_ARCH_TLB_FLUSH_ALL
 	select KVM_MMIO
 	select KVM_GENERIC_DIRTYLOG_READ_PROTECT
 	select KVM_XFER_TO_GUEST_WORK
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 01352f5838a0..8840f65e0e40 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -80,15 +80,15 @@ static bool memslot_is_logging(struct kvm_memory_slot *memslot)
 }
 
 /**
- * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8
+ * kvm_arch_flush_remote_tlbs() - flush all VM TLB entries for v7/8
  * @kvm:	pointer to kvm structure.
  *
  * Interface to HYP function to flush all VM TLB entries
  */
-void kvm_flush_remote_tlbs(struct kvm *kvm)
+int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 {
-	++kvm->stat.generic.remote_tlb_flush_requests;
 	kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
+	return 0;
 }
 
 static bool kvm_is_device_pfn(unsigned long pfn)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 277507463678..fefd3e3c8fe1 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -347,7 +347,6 @@ bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
 }
 EXPORT_SYMBOL_GPL(kvm_make_all_cpus_request);
 
-#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
 void kvm_flush_remote_tlbs(struct kvm *kvm)
 {
 	++kvm->stat.generic.remote_tlb_flush_requests;
@@ -368,7 +367,6 @@ void kvm_flush_remote_tlbs(struct kvm *kvm)
 		++kvm->stat.generic.remote_tlb_flush;
 }
 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
-#endif
 
 static void kvm_flush_shadow_all(struct kvm *kvm)
 {
-- 
2.39.0.246.g2a6d74b583-goog

Re: [PATCH 2/7] KVM: arm64: Use kvm_arch_flush_remote_tlbs()

[Oliver Upton]

Hi David,

On Thu, Jan 19, 2023 at 09:35:54AM -0800, David Matlack wrote:
> Use kvm_arch_flush_remote_tlbs() instead of
> CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL. The two mechanisms solve the same
> problem, allowing architecture-specific code to provide a non-IPI
> implementation of remote TLB flushing.
> 
> Dropping CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL allows KVM to standardize
> all architectures on kvm_arch_flush_remote_tlbs() instead of maintaining
> two mechanisms.
> 
> Opt to standardize on kvm_arch_flush_remote_tlbs() since it avoids
> duplicating the generic TLB stats across architectures that implement
> their own remote TLB flush.
> 
> This adds an extra function call to the ARM64 kvm_flush_remote_tlbs()
> path, but (I assume) that is a small cost in comparison to flushing
> remote TLBs.

A fair assumption indeed. The real pile up occurs on the DSB subsequent
to the TLBI.

> No functional change intended.
> 
> Signed-off-by: David Matlack <dmatlack@google.com>
> ---
>  arch/arm64/include/asm/kvm_host.h | 3 +++
>  arch/arm64/kvm/Kconfig            | 1 -
>  arch/arm64/kvm/mmu.c              | 6 +++---
>  virt/kvm/kvm_main.c               | 2 --
>  4 files changed, 6 insertions(+), 6 deletions(-)

I think you're missing the diff that actually drops the Kconfig opton
from virt/kvm/Kconfig.

--
Thanks,
Oliver

Re: [PATCH 2/7] KVM: arm64: Use kvm_arch_flush_remote_tlbs()

[David Matlack]

On Tue, Jan 24, 2023 at 9:17 AM Oliver Upton <oliver.upton@linux.dev> wrote:
> On Thu, Jan 19, 2023 at 09:35:54AM -0800, David Matlack wrote:
> >
> >  arch/arm64/include/asm/kvm_host.h | 3 +++
> >  arch/arm64/kvm/Kconfig            | 1 -
> >  arch/arm64/kvm/mmu.c              | 6 +++---
> >  virt/kvm/kvm_main.c               | 2 --
> >  4 files changed, 6 insertions(+), 6 deletions(-)
>
> I think you're missing the diff that actually drops the Kconfig opton
> from virt/kvm/Kconfig.

Indeed I am, thanks for catching that!

[PATCH 3/7] KVM: x86/mmu: Collapse kvm_flush_remote_tlbs_with_{range,address}() together

[David Matlack]

Collapse kvm_flush_remote_tlbs_with_range() and
kvm_flush_remote_tlbs_with_address() into a single function. This
eliminates some lines of code and a useless NULL check on the range
struct.

Opportunistically switch from ENOTSUPP to EOPNOTSUPP to make checkpatch
happy.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/x86/kvm/mmu/mmu.c | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index aeb240b339f5..7740ca52dab4 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -246,27 +246,20 @@ static inline bool kvm_available_flush_tlb_with_range(void)
 	return kvm_x86_ops.tlb_remote_flush_with_range;
 }
 
-static void kvm_flush_remote_tlbs_with_range(struct kvm *kvm,
-		struct kvm_tlb_range *range)
-{
-	int ret = -ENOTSUPP;
-
-	if (range && kvm_x86_ops.tlb_remote_flush_with_range)
-		ret = static_call(kvm_x86_tlb_remote_flush_with_range)(kvm, range);
-
-	if (ret)
-		kvm_flush_remote_tlbs(kvm);
-}
-
 void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
 		u64 start_gfn, u64 pages)
 {
 	struct kvm_tlb_range range;
+	int ret = -EOPNOTSUPP;
 
 	range.start_gfn = start_gfn;
 	range.pages = pages;
 
-	kvm_flush_remote_tlbs_with_range(kvm, &range);
+	if (kvm_x86_ops.tlb_remote_flush_with_range)
+		ret = static_call(kvm_x86_tlb_remote_flush_with_range)(kvm, &range);
+
+	if (ret)
+		kvm_flush_remote_tlbs(kvm);
 }
 
 static void mark_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 gfn,
-- 
2.39.0.246.g2a6d74b583-goog

[PATCH 4/7] KVM: x86/mmu: Rename kvm_flush_remote_tlbs_with_address()

[David Matlack]

Rename kvm_flush_remote_tlbs_with_address() to
kvm_flush_remote_tlbs_range(). This name is shorter, which reduces the
number of callsites that need to be broken up across multiple lines, and
more readable since it conveys a range of memory is being flushed rather
than a single address.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/x86/kvm/mmu/mmu.c          | 36 +++++++++++++++------------------
 arch/x86/kvm/mmu/mmu_internal.h |  3 +--
 arch/x86/kvm/mmu/paging_tmpl.h  |  4 ++--
 arch/x86/kvm/mmu/tdp_mmu.c      |  7 +++----
 4 files changed, 22 insertions(+), 28 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 7740ca52dab4..36ce3110b7da 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -246,8 +246,7 @@ static inline bool kvm_available_flush_tlb_with_range(void)
 	return kvm_x86_ops.tlb_remote_flush_with_range;
 }
 
-void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
-		u64 start_gfn, u64 pages)
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, u64 start_gfn, u64 pages)
 {
 	struct kvm_tlb_range range;
 	int ret = -EOPNOTSUPP;
@@ -806,7 +805,7 @@ static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp)
 	kvm_mmu_gfn_disallow_lpage(slot, gfn);
 
 	if (kvm_mmu_slot_gfn_write_protect(kvm, slot, gfn, PG_LEVEL_4K))
-		kvm_flush_remote_tlbs_with_address(kvm, gfn, 1);
+		kvm_flush_remote_tlbs_range(kvm, gfn, 1);
 }
 
 void track_possible_nx_huge_page(struct kvm *kvm, struct kvm_mmu_page *sp)
@@ -1180,8 +1179,8 @@ static void drop_large_spte(struct kvm *kvm, u64 *sptep, bool flush)
 	drop_spte(kvm, sptep);
 
 	if (flush)
-		kvm_flush_remote_tlbs_with_address(kvm, sp->gfn,
-			KVM_PAGES_PER_HPAGE(sp->role.level));
+		kvm_flush_remote_tlbs_range(kvm, sp->gfn,
+					    KVM_PAGES_PER_HPAGE(sp->role.level));
 }
 
 /*
@@ -1462,7 +1461,7 @@ static bool kvm_set_pte_rmap(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
 	}
 
 	if (need_flush && kvm_available_flush_tlb_with_range()) {
-		kvm_flush_remote_tlbs_with_address(kvm, gfn, 1);
+		kvm_flush_remote_tlbs_range(kvm, gfn, 1);
 		return false;
 	}
 
@@ -1632,8 +1631,8 @@ static void __rmap_add(struct kvm *kvm,
 		kvm->stat.max_mmu_rmap_size = rmap_count;
 	if (rmap_count > RMAP_RECYCLE_THRESHOLD) {
 		kvm_zap_all_rmap_sptes(kvm, rmap_head);
-		kvm_flush_remote_tlbs_with_address(
-				kvm, sp->gfn, KVM_PAGES_PER_HPAGE(sp->role.level));
+		kvm_flush_remote_tlbs_range(kvm, sp->gfn,
+					    KVM_PAGES_PER_HPAGE(sp->role.level));
 	}
 }
 
@@ -2398,7 +2397,7 @@ static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep,
 			return;
 
 		drop_parent_pte(child, sptep);
-		kvm_flush_remote_tlbs_with_address(vcpu->kvm, child->gfn, 1);
+		kvm_flush_remote_tlbs_range(vcpu->kvm, child->gfn, 1);
 	}
 }
 
@@ -2882,8 +2881,8 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, struct kvm_memory_slot *slot,
 	}
 
 	if (flush)
-		kvm_flush_remote_tlbs_with_address(vcpu->kvm, gfn,
-				KVM_PAGES_PER_HPAGE(level));
+		kvm_flush_remote_tlbs_range(vcpu->kvm, gfn,
+					    KVM_PAGES_PER_HPAGE(level));
 
 	pgprintk("%s: setting spte %llx\n", __func__, *sptep);
 
@@ -5814,9 +5813,8 @@ slot_handle_level_range(struct kvm *kvm, const struct kvm_memory_slot *memslot,
 
 		if (need_resched() || rwlock_needbreak(&kvm->mmu_lock)) {
 			if (flush && flush_on_yield) {
-				kvm_flush_remote_tlbs_with_address(kvm,
-						start_gfn,
-						iterator.gfn - start_gfn + 1);
+				kvm_flush_remote_tlbs_range(kvm, start_gfn,
+							    iterator.gfn - start_gfn + 1);
 				flush = false;
 			}
 			cond_resched_rwlock_write(&kvm->mmu_lock);
@@ -6171,8 +6169,7 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
 	}
 
 	if (flush)
-		kvm_flush_remote_tlbs_with_address(kvm, gfn_start,
-						   gfn_end - gfn_start);
+		kvm_flush_remote_tlbs_range(kvm, gfn_start, gfn_end - gfn_start);
 
 	kvm_mmu_invalidate_end(kvm, 0, -1ul);
 
@@ -6511,8 +6508,8 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
 			kvm_zap_one_rmap_spte(kvm, rmap_head, sptep);
 
 			if (kvm_available_flush_tlb_with_range())
-				kvm_flush_remote_tlbs_with_address(kvm, sp->gfn,
-					KVM_PAGES_PER_HPAGE(sp->role.level));
+				kvm_flush_remote_tlbs_range(kvm, sp->gfn,
+							    KVM_PAGES_PER_HPAGE(sp->role.level));
 			else
 				need_tlb_flush = 1;
 
@@ -6562,8 +6559,7 @@ void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
 	 * is observed by any other operation on the same memslot.
 	 */
 	lockdep_assert_held(&kvm->slots_lock);
-	kvm_flush_remote_tlbs_with_address(kvm, memslot->base_gfn,
-					   memslot->npages);
+	kvm_flush_remote_tlbs_range(kvm, memslot->base_gfn, memslot->npages);
 }
 
 void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm,
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index ac00bfbf32f6..e606a6d5e040 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -164,8 +164,7 @@ void kvm_mmu_gfn_allow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn);
 bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
 				    struct kvm_memory_slot *slot, u64 gfn,
 				    int min_level);
-void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
-					u64 start_gfn, u64 pages);
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, u64 start_gfn, u64 pages);
 unsigned int pte_list_count(struct kvm_rmap_head *rmap_head);
 
 extern int nx_huge_pages;
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index e5662dbd519c..fdad03f131c8 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -929,8 +929,8 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva, hpa_t root_hpa)
 
 			mmu_page_zap_pte(vcpu->kvm, sp, sptep, NULL);
 			if (is_shadow_present_pte(old_spte))
-				kvm_flush_remote_tlbs_with_address(vcpu->kvm,
-					sp->gfn, KVM_PAGES_PER_HPAGE(sp->role.level));
+				kvm_flush_remote_tlbs_range(vcpu->kvm, sp->gfn,
+							    KVM_PAGES_PER_HPAGE(sp->role.level));
 
 			if (!rmap_can_add(vcpu))
 				break;
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index bba33aea0fb0..7c21d15c58d8 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -680,8 +680,7 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
 	if (ret)
 		return ret;
 
-	kvm_flush_remote_tlbs_with_address(kvm, iter->gfn,
-					   KVM_PAGES_PER_HPAGE(iter->level));
+	kvm_flush_remote_tlbs_range(kvm, iter->gfn, KVM_PAGES_PER_HPAGE(iter->level));
 
 	/*
 	 * No other thread can overwrite the removed SPTE as they must either
@@ -1080,8 +1079,8 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu,
 		return RET_PF_RETRY;
 	else if (is_shadow_present_pte(iter->old_spte) &&
 		 !is_last_spte(iter->old_spte, iter->level))
-		kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn,
-						   KVM_PAGES_PER_HPAGE(iter->level + 1));
+		kvm_flush_remote_tlbs_range(vcpu->kvm, sp->gfn,
+					    KVM_PAGES_PER_HPAGE(iter->level + 1));
 
 	/*
 	 * If the page fault was caused by a write but the page is write
-- 
2.39.0.246.g2a6d74b583-goog

Re: [PATCH 4/7] KVM: x86/mmu: Rename kvm_flush_remote_tlbs_with_address()

[Sean Christopherson]

On Thu, Jan 19, 2023, David Matlack wrote:
> Rename kvm_flush_remote_tlbs_with_address() to
> kvm_flush_remote_tlbs_range(). This name is shorter, which reduces the
> number of callsites that need to be broken up across multiple lines, and
> more readable since it conveys a range of memory is being flushed rather
> than a single address.

FYI, this conflicts with Hou's series, which I'm in the process of queueing for
v6.3.

https://lore.kernel.org/all/cover.1665214747.git.houwenlong.hwl@antgroup.com

Re: [PATCH 4/7] KVM: x86/mmu: Rename kvm_flush_remote_tlbs_with_address()

[David Matlack]

On Thu, Jan 19, 2023 at 10:17 AM Sean Christopherson <seanjc@google.com> wrote:
>
> On Thu, Jan 19, 2023, David Matlack wrote:
> > Rename kvm_flush_remote_tlbs_with_address() to
> > kvm_flush_remote_tlbs_range(). This name is shorter, which reduces the
> > number of callsites that need to be broken up across multiple lines, and
> > more readable since it conveys a range of memory is being flushed rather
> > than a single address.
>
> FYI, this conflicts with Hou's series, which I'm in the process of queueing for
> v6.3.
>
> https://lore.kernel.org/all/cover.1665214747.git.houwenlong.hwl@antgroup.com

Ack. I can resend on top of Hou's once it's queued.

[PATCH 5/7] KVM: x86/MMU: Use gfn_t in kvm_flush_remote_tlbs_range()

[David Matlack]

Use gfn_t instead of u64 for the start_gfn parameter to
kvm_flush_remote_tlbs_range(), since that is the standard type for GFNs
throughout KVM.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/x86/kvm/mmu/mmu.c          | 2 +-
 arch/x86/kvm/mmu/mmu_internal.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 36ce3110b7da..1e2c2d711dbb 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -246,7 +246,7 @@ static inline bool kvm_available_flush_tlb_with_range(void)
 	return kvm_x86_ops.tlb_remote_flush_with_range;
 }
 
-void kvm_flush_remote_tlbs_range(struct kvm *kvm, u64 start_gfn, u64 pages)
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages)
 {
 	struct kvm_tlb_range range;
 	int ret = -EOPNOTSUPP;
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index e606a6d5e040..851982a25502 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -164,7 +164,7 @@ void kvm_mmu_gfn_allow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn);
 bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
 				    struct kvm_memory_slot *slot, u64 gfn,
 				    int min_level);
-void kvm_flush_remote_tlbs_range(struct kvm *kvm, u64 start_gfn, u64 pages);
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages);
 unsigned int pte_list_count(struct kvm_rmap_head *rmap_head);
 
 extern int nx_huge_pages;
-- 
2.39.0.246.g2a6d74b583-goog

[PATCH 6/7] KVM: Allow range-based TLB invalidation from common code

[David Matlack]

Make kvm_flush_remote_tlbs_range() visible in common code and create a
default implementation that just invalidates the whole TLB.

This paves the way for several future cleanups:
 - Introduction of range-based TLBI on ARM.
 - Eliminating kvm_arch_flush_remote_tlbs_memslot()
 - Moving the KVM/x86 TDP MMU to common code.

No functional change intended.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/x86/include/asm/kvm_host.h |  3 +++
 arch/x86/kvm/mmu/mmu.c          |  5 ++---
 arch/x86/kvm/mmu/mmu_internal.h |  1 -
 include/linux/kvm_host.h        |  9 +++++++++
 virt/kvm/kvm_main.c             | 13 +++++++++++++
 5 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1bacc3de2432..420713ac8916 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1799,6 +1799,9 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 		return -ENOTSUPP;
 }
 
+#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE
+int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages);
+
 #define kvm_arch_pmi_in_guest(vcpu) \
 	((vcpu) && (vcpu)->arch.handling_intr_from_guest)
 
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 1e2c2d711dbb..491c28d22cbe 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -246,7 +246,7 @@ static inline bool kvm_available_flush_tlb_with_range(void)
 	return kvm_x86_ops.tlb_remote_flush_with_range;
 }
 
-void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages)
+int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages)
 {
 	struct kvm_tlb_range range;
 	int ret = -EOPNOTSUPP;
@@ -257,8 +257,7 @@ void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages)
 	if (kvm_x86_ops.tlb_remote_flush_with_range)
 		ret = static_call(kvm_x86_tlb_remote_flush_with_range)(kvm, &range);
 
-	if (ret)
-		kvm_flush_remote_tlbs(kvm);
+	return ret;
 }
 
 static void mark_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 gfn,
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 851982a25502..d5599f2d3f96 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -164,7 +164,6 @@ void kvm_mmu_gfn_allow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn);
 bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
 				    struct kvm_memory_slot *slot, u64 gfn,
 				    int min_level);
-void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t start_gfn, u64 pages);
 unsigned int pte_list_count(struct kvm_rmap_head *rmap_head);
 
 extern int nx_huge_pages;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 76711afe4d17..acfb17d9b44d 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1356,6 +1356,7 @@ int kvm_vcpu_yield_to(struct kvm_vcpu *target);
 void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu, bool usermode_vcpu_not_eligible);
 
 void kvm_flush_remote_tlbs(struct kvm *kvm);
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 pages);
 
 #ifdef KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE
 int kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int min);
@@ -1484,6 +1485,14 @@ static inline int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 }
 #endif
 
+#ifndef __KVM_HAVE_ARCH_FLUSH_REMOTE_TLBS_RANGE
+static inline int kvm_arch_flush_remote_tlbs_range(struct kvm *kvm,
+						   gfn_t gfn, u64 pages)
+{
+	return -EOPNOTSUPP;
+}
+#endif
+
 #ifdef __KVM_HAVE_ARCH_NONCOHERENT_DMA
 void kvm_arch_register_noncoherent_dma(struct kvm *kvm);
 void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index fefd3e3c8fe1..c9fc693a39d9 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -368,6 +368,19 @@ void kvm_flush_remote_tlbs(struct kvm *kvm)
 }
 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
 
+void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 pages)
+{
+	if (!kvm_arch_flush_remote_tlbs_range(kvm, gfn, pages))
+		return;
+
+	/*
+	 * Fall back to a flushing entire TLBs if the architecture range-based
+	 * TLB invalidation is unsupported or can't be performed for whatever
+	 * reason.
+	 */
+	kvm_flush_remote_tlbs(kvm);
+}
+
 static void kvm_flush_shadow_all(struct kvm *kvm)
 {
 	kvm_arch_flush_shadow_all(kvm);
-- 
2.39.0.246.g2a6d74b583-goog

Re: [PATCH 6/7] KVM: Allow range-based TLB invalidation from common code

[Oliver Upton]

On Thu, Jan 19, 2023 at 09:35:58AM -0800, David Matlack wrote:
> Make kvm_flush_remote_tlbs_range() visible in common code and create a
> default implementation that just invalidates the whole TLB.
> 
> This paves the way for several future cleanups:
>  - Introduction of range-based TLBI on ARM.

nit: this is definitely a new feature, not a cleanup :)

--
Thanks,
Oliver

[PATCH 7/7] KVM: Move kvm_arch_flush_remote_tlbs_memslot() to common code

[David Matlack]

Move kvm_arch_flush_remote_tlbs_memslot() to common code and drop
"arch_" from the name. kvm_arch_flush_remote_tlbs_memslot() is just a
range-based TLB invalidation where the range is defined by the memslot.
Now that kvm_flush_remote_tlbs_range() can be called from common code we
can just use that and drop a bunch of duplicate code from the arch
directories.

Note this adds a lockdep assertion for slots_lock being held when
calling kvm_flush_remote_tlbs_memslot(), which was previously only
asserted on x86. MIPS has calls to kvm_flush_remote_tlbs_memslot(),
but they all hold the slots_lock, so the lockdep assertion continues to
hold true.

Also drop the CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT ifdef gating
kvm_flush_remote_tlbs_memslot(), since it is no longer necessary.

Signed-off-by: David Matlack <dmatlack@google.com>
---
 arch/arm64/kvm/arm.c     |  6 ------
 arch/mips/kvm/mips.c     | 10 ++--------
 arch/riscv/kvm/mmu.c     |  6 ------
 arch/x86/kvm/mmu/mmu.c   | 16 +---------------
 arch/x86/kvm/x86.c       |  2 +-
 include/linux/kvm_host.h |  7 +++----
 virt/kvm/kvm_main.c      | 18 ++++++++++++++++--
 7 files changed, 23 insertions(+), 42 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 698787ed87e9..54d5d0733b98 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1420,12 +1420,6 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 
 }
 
-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
-					const struct kvm_memory_slot *memslot)
-{
-	kvm_flush_remote_tlbs(kvm);
-}
-
 static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
 					struct kvm_arm_device_addr *dev_addr)
 {
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 2e54e5fd8daa..9f9a7ba7eb2b 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -199,7 +199,7 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
 	/* Flush slot from GPA */
 	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
 			      slot->base_gfn + slot->npages - 1);
-	kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
+	kvm_flush_remote_tlbs_memslot(kvm, slot);
 	spin_unlock(&kvm->mmu_lock);
 }
 
@@ -235,7 +235,7 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
 					new->base_gfn + new->npages - 1);
 		if (needs_flush)
-			kvm_arch_flush_remote_tlbs_memslot(kvm, new);
+			kvm_flush_remote_tlbs_memslot(kvm, new);
 		spin_unlock(&kvm->mmu_lock);
 	}
 }
@@ -987,12 +987,6 @@ int kvm_arch_flush_remote_tlbs(struct kvm *kvm)
 	return 1;
 }
 
-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
-					const struct kvm_memory_slot *memslot)
-{
-	kvm_flush_remote_tlbs(kvm);
-}
-
 long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
 {
 	long r;
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index 66ef19676fe4..87f30487f59f 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -406,12 +406,6 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 {
 }
 
-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
-					const struct kvm_memory_slot *memslot)
-{
-	kvm_flush_remote_tlbs(kvm);
-}
-
 void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free)
 {
 }
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 491c28d22cbe..4af85888c98b 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6528,7 +6528,7 @@ static void kvm_rmap_zap_collapsible_sptes(struct kvm *kvm,
 	 */
 	if (slot_handle_level(kvm, slot, kvm_mmu_zap_collapsible_spte,
 			      PG_LEVEL_4K, KVM_MAX_HUGEPAGE_LEVEL - 1, true))
-		kvm_arch_flush_remote_tlbs_memslot(kvm, slot);
+		kvm_flush_remote_tlbs_memslot(kvm, slot);
 }
 
 void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm,
@@ -6547,20 +6547,6 @@ void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm,
 	}
 }
 
-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
-					const struct kvm_memory_slot *memslot)
-{
-	/*
-	 * All current use cases for flushing the TLBs for a specific memslot
-	 * related to dirty logging, and many do the TLB flush out of mmu_lock.
-	 * The interaction between the various operations on memslot must be
-	 * serialized by slots_locks to ensure the TLB flush from one operation
-	 * is observed by any other operation on the same memslot.
-	 */
-	lockdep_assert_held(&kvm->slots_lock);
-	kvm_flush_remote_tlbs_range(kvm, memslot->base_gfn, memslot->npages);
-}
-
 void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm,
 				   const struct kvm_memory_slot *memslot)
 {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 508074e47bc0..ea7bb4035a60 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12617,7 +12617,7 @@ static void kvm_mmu_slot_apply_flags(struct kvm *kvm,
 		 * See is_writable_pte() for more details (the case involving
 		 * access-tracked SPTEs is particularly relevant).
 		 */
-		kvm_arch_flush_remote_tlbs_memslot(kvm, new);
+		kvm_flush_remote_tlbs_memslot(kvm, new);
 	}
 }
 
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index acfb17d9b44d..12dfecd27c9d 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1357,6 +1357,8 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu, bool usermode_vcpu_not_eligible);
 
 void kvm_flush_remote_tlbs(struct kvm *kvm);
 void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 pages);
+void kvm_flush_remote_tlbs_memslot(struct kvm *kvm,
+				   const struct kvm_memory_slot *memslot);
 
 #ifdef KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE
 int kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int min);
@@ -1385,10 +1387,7 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
 					unsigned long mask);
 void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot);
 
-#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
-void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
-					const struct kvm_memory_slot *memslot);
-#else /* !CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
+#ifndef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log);
 int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log,
 		      int *is_dirty, struct kvm_memory_slot **memslot);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c9fc693a39d9..9c10cd191a71 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -381,6 +381,20 @@ void kvm_flush_remote_tlbs_range(struct kvm *kvm, gfn_t gfn, u64 pages)
 	kvm_flush_remote_tlbs(kvm);
 }
 
+void kvm_flush_remote_tlbs_memslot(struct kvm *kvm,
+				   const struct kvm_memory_slot *memslot)
+{
+	/*
+	 * All current use cases for flushing the TLBs for a specific memslot
+	 * related to dirty logging, and many do the TLB flush out of mmu_lock.
+	 * The interaction between the various operations on memslot must be
+	 * serialized by slots_locks to ensure the TLB flush from one operation
+	 * is observed by any other operation on the same memslot.
+	 */
+	lockdep_assert_held(&kvm->slots_lock);
+	kvm_flush_remote_tlbs_range(kvm, memslot->base_gfn, memslot->npages);
+}
+
 static void kvm_flush_shadow_all(struct kvm *kvm)
 {
 	kvm_arch_flush_shadow_all(kvm);
@@ -2188,7 +2202,7 @@ static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log)
 	}
 
 	if (flush)
-		kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
+		kvm_flush_remote_tlbs_memslot(kvm, memslot);
 
 	if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
 		return -EFAULT;
@@ -2305,7 +2319,7 @@ static int kvm_clear_dirty_log_protect(struct kvm *kvm,
 	KVM_MMU_UNLOCK(kvm);
 
 	if (flush)
-		kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
+		kvm_flush_remote_tlbs_memslot(kvm, memslot);
 
 	return 0;
 }
-- 
2.39.0.246.g2a6d74b583-goog

Re: [PATCH 0/7] KVM: Add a common API for range-based TLB invalidation

[Sean Christopherson]

On Thu, Jan 19, 2023, David Matlack wrote:
> This series introduces a common API for performing range-based TLB
> invalidation. This is then used to supplant
> kvm_arch_flush_remote_tlbs_memslot() and pave the way for two other
> patch series:
> 
> 1. https://lore.kernel.org/kvm/20230109215347.3119271-1-rananta@google.com/
> 
>   Adds ARM support for range-based TLB invalidation and needs a
>   mechanism to invoke it from common code. This series provides such a
>   mechanism via kvm_arch_flush_remote_tlbs_range().
> 
> 2. https://lore.kernel.org/kvm/20221208193857.4090582-1-dmatlack@google.com/
> 
>   Refactors the TDP MMU into common code, which requires an API for
>   range-based TLB invaliation.
> 
> This series is based on patches 29-33 from (2.), but I made some further
> cleanups after looking at it a second time.
> 
> Tested on x86_64 and ARM64 using KVM selftests.

Did a quick read through, didn't see anything I disagree with.

Is there any urgency to getting this merged?  If not, due to the dependencies
with x86 stuff queued for 6.3, and because of the cross-architecture changes, it
might be easiest to plan on landing this in 6.4.  That would allow Paolo to create
an immutable topic branch fairly early on.

Re: [PATCH 0/7] KVM: Add a common API for range-based TLB invalidation

[Oliver Upton]

On Wed, Jan 25, 2023 at 12:46:59AM +0000, Sean Christopherson wrote:
> On Thu, Jan 19, 2023, David Matlack wrote:
> > This series introduces a common API for performing range-based TLB
> > invalidation. This is then used to supplant
> > kvm_arch_flush_remote_tlbs_memslot() and pave the way for two other
> > patch series:
> > 
> > 1. https://lore.kernel.org/kvm/20230109215347.3119271-1-rananta@google.com/
> > 
> >   Adds ARM support for range-based TLB invalidation and needs a
> >   mechanism to invoke it from common code. This series provides such a
> >   mechanism via kvm_arch_flush_remote_tlbs_range().
> > 
> > 2. https://lore.kernel.org/kvm/20221208193857.4090582-1-dmatlack@google.com/
> > 
> >   Refactors the TDP MMU into common code, which requires an API for
> >   range-based TLB invaliation.
> > 
> > This series is based on patches 29-33 from (2.), but I made some further
> > cleanups after looking at it a second time.
> > 
> > Tested on x86_64 and ARM64 using KVM selftests.
> 
> Did a quick read through, didn't see anything I disagree with.

LGTM for the tiny amount of arm64 changes, though I imagine David will
do a v2 to completely get rid of the affected Kconfig.

> Is there any urgency to getting this merged?  If not, due to the dependencies
> with x86 stuff queued for 6.3, and because of the cross-architecture changes, it
> might be easiest to plan on landing this in 6.4.  That would allow Paolo to create
> an immutable topic branch fairly early on.

+1, that buys us some time to go through the rounds on the arm64 side
such that we could possibly stack the TLBIRANGE work on top.

--
Thanks,
Oliver

Re: [PATCH 0/7] KVM: Add a common API for range-based TLB invalidation

[David Matlack]

On Tue, Jan 24, 2023 at 4:51 PM Oliver Upton <oliver.upton@linux.dev> wrote:
> On Wed, Jan 25, 2023 at 12:46:59AM +0000, Sean Christopherson wrote:
> > On Thu, Jan 19, 2023, David Matlack wrote:
> >
> > Did a quick read through, didn't see anything I disagree with.
>
> LGTM for the tiny amount of arm64 changes, though I imagine David will
> do a v2 to completely get rid of the affected Kconfig.

Thanks both for taking a look.

> > Is there any urgency to getting this merged?  If not, due to the dependencies
> > with x86 stuff queued for 6.3, and because of the cross-architecture changes, it
> > might be easiest to plan on landing this in 6.4.  That would allow Paolo to create
> > an immutable topic branch fairly early on.
>
> +1, that buys us some time to go through the rounds on the arm64 side
> such that we could possibly stack the TLBIRANGE work on top.

The main benefit of merging in 6.3 would be to make Raghavendra's life
simpler/easier so he can build the next version of his arm64 TLBI
series on top. But I guess he can still do that with a topic branch.

I'll go ahead and send a v2 on top of the changes from Hou you queued
for 6.3, Sean, and we can plan on landing that in 6.4 (barring any
further feedback or conflicts).