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Peter Anvin" , Ard Biesheuvel , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Jim Mattson , Andy Lutomirski , Dave Hansen , Sergio Lopez , Peter Zijlstra , Srinivas Pandruvada , David Rientjes , Dov Murik , Tobin Feldman-Fitzthum , Borislav Petkov , Michael Roth , Vlastimil Babka , "Kirill A . Shutemov" , Andi Kleen , Tony Luck , Marc Orr , Sathyanarayanan Kuppuswamy , Alper Gun , "Dr. David Alan Gilbert" , jarkko@kernel.org Content-Type: text/plain; charset="UTF-8" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1660928060; a=rsa-sha256; cv=none; b=gHpddJl2Vp8pTkQt27htXhom2Tle8cd3+Ov77hNgBrkpLXYRKkknjbxBCY1Bo0FLTieMGp EV1J6r1AlvHjP5jjC/jwPjwIsMd8yU8FpMtsh+KpLitwcNeNN6gZbm2i5P0UQ092WL98E5 w7IcXBNqXwzKh0cQ8Ye5pq9wORtDcxQ= ARC-Authentication-Results: i=1; imf29.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=rev22bDg; spf=pass (imf29.hostedemail.com: domain of pgonda@google.com designates 209.85.208.169 as permitted sender) smtp.mailfrom=pgonda@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1660928060; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=AhTWQcbRqLOHVkblJK8G++davTd8BoOGzTOxaJ8TciQ=; b=vB6mvQoIrr6kelj9qV2OLde5kuGWcHlLbqkxsrDOPQQwV2NjfKV33llKScIPRZXe/GbnI9 o0tvS06XWWaWpwbg0bAG0Jke6pBzVCZmyMniW+820qXMkly7FK9IBksTLdNCh8SBbl9FE2 dVlo+ayZLzrX6w8e702HRVCF2bR7xg8= X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 0C5B4120019 X-Rspam-User: Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=rev22bDg; spf=pass (imf29.hostedemail.com: domain of pgonda@google.com designates 209.85.208.169 as permitted sender) smtp.mailfrom=pgonda@google.com; dmarc=pass (policy=reject) header.from=google.com X-Stat-Signature: rgk3thmxxg8g87ifmcwxe5wubrn4tp38 X-HE-Tag: 1660928059-17352 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > + > +static int __snp_handle_page_state_change(struct kvm_vcpu *vcpu, enum psc_op op, gpa_t gpa, > + int level) > +{ > + struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; > + struct kvm *kvm = vcpu->kvm; > + int rc, npt_level; > + kvm_pfn_t pfn; > + gpa_t gpa_end; > + > + gpa_end = gpa + page_level_size(level); > + > + while (gpa < gpa_end) { > + /* > + * If the gpa is not present in the NPT then build the NPT. > + */ > + rc = snp_check_and_build_npt(vcpu, gpa, level); > + if (rc) > + return -EINVAL; > + > + if (op == SNP_PAGE_STATE_PRIVATE) { > + hva_t hva; > + > + if (snp_gpa_to_hva(kvm, gpa, &hva)) > + return -EINVAL; > + > + /* > + * Verify that the hva range is registered. This enforcement is > + * required to avoid the cases where a page is marked private > + * in the RMP table but never gets cleanup during the VM > + * termination path. > + */ > + mutex_lock(&kvm->lock); > + rc = is_hva_registered(kvm, hva, page_level_size(level)); > + mutex_unlock(&kvm->lock); > + if (!rc) > + return -EINVAL; > + > + /* > + * Mark the userspace range unmerable before adding the pages > + * in the RMP table. > + */ > + mmap_write_lock(kvm->mm); > + rc = snp_mark_unmergable(kvm, hva, page_level_size(level)); > + mmap_write_unlock(kvm->mm); > + if (rc) > + return -EINVAL; > + } > + > + write_lock(&kvm->mmu_lock); > + > + rc = kvm_mmu_get_tdp_walk(vcpu, gpa, &pfn, &npt_level); > + if (!rc) { > + /* > + * This may happen if another vCPU unmapped the page > + * before we acquire the lock. Retry the PSC. > + */ > + write_unlock(&kvm->mmu_lock); > + return 0; > + } I think we want to return -EAGAIN or similar if we want the caller to retry, right? I think returning 0 here hides the error. > + > + /* > + * Adjust the level so that we don't go higher than the backing > + * page level. > + */ > + level = min_t(size_t, level, npt_level); > + > + trace_kvm_snp_psc(vcpu->vcpu_id, pfn, gpa, op, level); > + > + switch (op) { > + case SNP_PAGE_STATE_SHARED: > + rc = snp_make_page_shared(kvm, gpa, pfn, level); > + break; > + case SNP_PAGE_STATE_PRIVATE: > + rc = rmp_make_private(pfn, gpa, level, sev->asid, false); > + break; > + default: > + rc = -EINVAL; > + break; > + } > + > + write_unlock(&kvm->mmu_lock); > + > + if (rc) { > + pr_err_ratelimited("Error op %d gpa %llx pfn %llx level %d rc %d\n", > + op, gpa, pfn, level, rc); > + return rc; > + } > + > + gpa = gpa + page_level_size(level); > + } > + > + return 0; > +} > +