This is a note to let you know that I've just added the patch titled
KVM: PPC: e500: Mark "struct page" pfn accessed before dropping mmu_lock
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-ppc-e500-mark-struct-page-pfn-accessed-before-dr.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2816dd4eaca5820f3b1b03238cfb205b0778c159
Author: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Thu Oct 10 11:23:55 2024 -0700
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@xxxxxxxxxx>
Tested-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Message-ID: <20241010182427.1434605-54-seanjc@xxxxxxxxxx>
Stable-dep-of: 87ecfdbc699c ("KVM: e500: always restore irqs")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
index b40d31cd44f7f..80f0b30abc74c 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;
}
