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Shutemov" Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, x86@kernel.org, linux-coco@lists.linux.dev, linux-kernel@vger.kernel.org, Ira Weiny , Kai Huang , Michael Roth , Yan Zhao , Vishal Annapurve , Rick Edgecombe , Ackerley Tng , Binbin Wu Content-Type: text/plain; charset="UTF-8" Return -EIO immediately from tdx_sept_zap_private_spte() if the number of to-be-added pages underflows, so that the following "KVM_BUG_ON(err, kvm)" isn't also triggered. Isolating the check from the "is premap error" if-statement will also allow adding a lockdep assertion that premap errors are encountered if and only if slots_lock is held. Reviewed-by: Rick Edgecombe Reviewed-by: Binbin Wu Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/tdx.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index f5cbcbf4e663..220989a1e085 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1721,8 +1721,10 @@ static int tdx_sept_zap_private_spte(struct kvm *kvm, gfn_t gfn, err = tdh_mem_range_block(&kvm_tdx->td, gpa, tdx_level, &entry, &level_state); tdx_no_vcpus_enter_stop(kvm); } - if (tdx_is_sept_zap_err_due_to_premap(kvm_tdx, err, entry, level) && - !KVM_BUG_ON(!atomic64_read(&kvm_tdx->nr_premapped), kvm)) { + if (tdx_is_sept_zap_err_due_to_premap(kvm_tdx, err, entry, level)) { + if (KVM_BUG_ON(!atomic64_read(&kvm_tdx->nr_premapped), kvm)) + return -EIO; + atomic64_dec(&kvm_tdx->nr_premapped); return 0; } -- 2.51.0.858.gf9c4a03a3a-goog