From dc94a0bbeb198f594d4f2e99cfb710d8c696eea2 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@google.com>
Date: Thu, 10 Oct 2024 11:23:55 -0700
Subject: [PATCH] KVM: PPC: e500: Mark "struct page" pfn accessed before
 dropping mmu_lock

[ Upstream commit 84cf78dcd9d65c45ab73998d4ad50f433d53fb93 ]

Mark pages accessed before dropping mmu_lock when faulting in guest memory
so that shadow_map() can convert to kvm_release_faultin_page() without
tripping its lockdep assertion on mmu_lock being held.  Marking pages
accessed outside of mmu_lock is ok (not great, but safe), but marking
pages _dirty_ outside of mmu_lock can make filesystems unhappy.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Tested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <20241010182427.1434605-54-seanjc@google.com>
Stable-dep-of: 87ecfdbc699c ("KVM: e500: always restore irqs")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/kvm/e500_mmu_host.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
index 4a086724db8c4..29f3e3463f400 100644
--- a/arch/powerpc/kvm/e500_mmu_host.c
+++ b/arch/powerpc/kvm/e500_mmu_host.c
@@ -498,11 +498,9 @@ static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 	kvmppc_mmu_flush_icache(pfn);
 
 out:
-	spin_unlock(&kvm->mmu_lock);
-
 	/* Drop refcount on page, so that mmu notifiers can clear it */
 	kvm_release_pfn_clean(pfn);
-
+	spin_unlock(&kvm->mmu_lock);
 	return ret;
 }
 
-- 
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