[v13,58/85] KVM: RISC-V: Mark "struct page" pfns accessed before dropping mmu_lock

Commit Message

Sean Christopherson Oct. 10, 2024, 6:24 p.m. UTC

Mark pages accessed before dropping mmu_lock when faulting in guest memory
so that RISC-V 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 (see the link below).
Do both under mmu_lock to minimize the chances of doing the wrong thing in
the future.

Link: https://lore.kernel.org/all/[e-mail]
Reviewed-by: Andrew Jones <[e-mail]>
Acked-by: Anup Patel <[e-mail]>
Signed-off-by: Sean Christopherson <[e-mail]>
---
 arch/riscv/kvm/mmu.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Patch

diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index 06aa5a0d056d..2e9aee518142 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -682,11 +682,11 @@  int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
 
 out_unlock:
 	if ((!ret || ret == -EEXIST) && writable)
-		kvm_set_pfn_dirty(hfn);
+		kvm_release_pfn_dirty(hfn);
+	else
+		kvm_release_pfn_clean(hfn);
 
 	spin_unlock(&kvm->mmu_lock);
-	kvm_set_pfn_accessed(hfn);
-	kvm_release_pfn_clean(hfn);
 	return ret;
 }