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Subject[PATCH tip/core/rcu 17/24] kvm: mmu: page_track: Fix RCU list API usage
Date
From: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>

Use hlist_for_each_entry_srcu() instead of hlist_for_each_entry_rcu()
as it also checkes if the right lock is held.
Using hlist_for_each_entry_rcu() with a condition argument will not
report the cases where a SRCU protected list is traversed using
rcu_read_lock(). Hence, use hlist_for_each_entry_srcu().

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: <kvm@vger.kernel.org>
---
arch/x86/kvm/mmu/page_track.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c
index a84a141..8443a67 100644
--- a/arch/x86/kvm/mmu/page_track.c
+++ b/arch/x86/kvm/mmu/page_track.c
@@ -229,7 +229,8 @@ void kvm_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new,
return;

idx = srcu_read_lock(&head->track_srcu);
- hlist_for_each_entry_rcu(n, &head->track_notifier_list, node)
+ hlist_for_each_entry_srcu(n, &head->track_notifier_list, node,
+ srcu_read_lock_held(&head->track_srcu))
if (n->track_write)
n->track_write(vcpu, gpa, new, bytes, n);
srcu_read_unlock(&head->track_srcu, idx);
@@ -254,7 +255,8 @@ void kvm_page_track_flush_slot(struct kvm *kvm, struct kvm_memory_slot *slot)
return;

idx = srcu_read_lock(&head->track_srcu);
- hlist_for_each_entry_rcu(n, &head->track_notifier_list, node)
+ hlist_for_each_entry_srcu(n, &head->track_notifier_list, node,
+ srcu_read_lock_held(&head->track_srcu))
if (n->track_flush_slot)
n->track_flush_slot(kvm, slot, n);
srcu_read_unlock(&head->track_srcu, idx);
--
2.9.5
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