From nobody Fri Dec 19 04:53:43 2025 Received: from mail-ed1-f73.google.com (mail-ed1-f73.google.com [209.85.208.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 332AC1FF1C8 for ; Wed, 18 Dec 2024 19:41:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734550900; cv=none; b=c/bw0ebppR6UJtItMGqwUkpX1/kSfjm6JUZn5lAay9hMPkFGeCJZvn0V4uK4nrRfh9yeIZj2JgNzznWUiX9xl3VoXtyz/7gmW5VV4hUOpOpN0vrbFxyXttPtVB/RmX2vDfiyxxt6UO4vigqtfZcgGLKMNaEu68zMf3hQJXk3hmI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734550900; c=relaxed/simple; bh=2tobAH5K5EZR3mMhXSKXYYFzfChriI1rgilcYZ+TGx0=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=nd/2EkBPcyCec7vXHczBIhltk5zOzU1cY4DFcH3yKUhjObzjbbdQVNeVhG/POohyrLdFZxJ/aHunqEKB3Sck9fnuws03oz0uf/tvtEP+zBhp9OD7llTFRAxGI4KKzcostbQLpt8U+TdKGspw+THEBffzYX1QO0vzM2q8mOj/qSQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--qperret.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=GVeMVOYA; arc=none smtp.client-ip=209.85.208.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--qperret.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="GVeMVOYA" Received: by mail-ed1-f73.google.com with SMTP id 4fb4d7f45d1cf-5d124077928so6350a12.0 for ; Wed, 18 Dec 2024 11:41:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1734550897; x=1735155697; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=hkfvAMeAqasaarDCC25uz9tXymaAjZWepO/HImSI4Yg=; b=GVeMVOYAXL2/NIiRbRUkEyfJ1ymJNsHZfzCUa8j9Zcet1E95QlrrY31V8CLTypDuHr g2rAHiuVqxhtWHHA8STZvoX6KTOfelQPc+Me3/EXm0Q4k/pcCTXLVdgfmsz6MxqWyfcQ KYc3PPtocBxswYwXXELi5kdnf+/nXxKdTFOSDzRyCPc+hzYVJPR85pN+CLwoHjDw5xfM 0yUUJ857NDYxw16j6CBXPiZe9WVAOAjBx/Ol5vvwErGU9zHE/EV9OwCukfLgRW87B6ql RV60x+uhyJMqoC5ZBGquSjmSvGdf/7gR8dFAdYTX3spO2thno0fFgz9okHikoKiKTeZq ekJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734550897; x=1735155697; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=hkfvAMeAqasaarDCC25uz9tXymaAjZWepO/HImSI4Yg=; b=XijMWX8iZkFHd4wGT0nKVu1j5jNmVKMURySpj7BJnKEK37dUdPpcC9oJmANZ04pQ2O SBKY8ppJmvzyhwMj1dCZXR9rXl+BfstgXLUoZCgyl+Fwc9eJ23EIBjJiruTC/Neau9Cc O/NUPi7bUPyETyZxmIIxre0ahKo4Sv5iouiDrDwjX8xScVW7iyYaZPLPU8gAdVcD6sx0 tnSgpc9ZjvtcJ1y0/oVAcPv+2rJMCcfk48e+pXu7n95rlTaGq4dlXpQJnqPL/Oo7RPsp BdjH1+NQI+oKS7vCObCch6omPaT4l/9Fp2WpP4XsyL8DPOZontEjw7LTFvc93nVoJwI7 Ec4Q== X-Forwarded-Encrypted: i=1; AJvYcCV1a6TahprQj03xgHlITYQisSnZ5KkkzXA4jwwl+jPFqke76SlyKg/IWXLT1p3LJHS9/9I0CSg+c1avFdQ=@vger.kernel.org X-Gm-Message-State: AOJu0YzO0bgfhDn95JfVvMkVvnfJHXuDXKIVIqtX7rvwghL/6QGyEWHX EXTMm8dvZu73zzDEi+nYtxtwxP5vh6Hd4Y7FBJuv+xvCnVu79yCOkje8gNGn5oUWJaR4CN7RiJc XdwCH8w== X-Google-Smtp-Source: AGHT+IGSBECViplx1U+nRtyXTDKvrUbyI+0W4ITB//TrX14agtn1suD5UatvN7l8zoDc+3G2GrjvLEAvKgAZ X-Received: from edb22.prod.google.com ([2002:a05:6402:2396:b0:5d7:f279:523e]) (user=qperret job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:2550:b0:5d2:7270:611f with SMTP id 4fb4d7f45d1cf-5d7ee3ff1famr4439977a12.22.1734550897647; Wed, 18 Dec 2024 11:41:37 -0800 (PST) Date: Wed, 18 Dec 2024 19:40:57 +0000 In-Reply-To: <20241218194059.3670226-1-qperret@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241218194059.3670226-1-qperret@google.com> X-Mailer: git-send-email 2.47.1.613.gc27f4b7a9f-goog Message-ID: <20241218194059.3670226-17-qperret@google.com> Subject: [PATCH v4 16/18] KVM: arm64: Introduce __pkvm_tlb_flush_vmid() From: Quentin Perret To: Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon Cc: Fuad Tabba , Vincent Donnefort , Sebastian Ene , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Introduce a new hypercall to flush the TLBs of non-protected guests. The host kernel will be responsible for issuing this hypercall after changing stage-2 permissions using the __pkvm_host_relax_guest_perms() or __pkvm_host_wrprotect_guest() paths. This is left under the host's responsibility for performance reasons. Note however that the TLB maintenance for all *unmap* operations still remains entirely under the hypervisor's responsibility for security reasons -- an unmapped page may be donated to another entity, so a stale TLB entry could be used to leak private data. Tested-by: Fuad Tabba Reviewed-by: Fuad Tabba Signed-off-by: Quentin Perret --- arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/kvm/hyp/nvhe/hyp-main.c | 17 +++++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_= asm.h index a3b07db2776c..002088c6e297 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -87,6 +87,7 @@ enum __kvm_host_smccc_func { __KVM_HOST_SMCCC_FUNC___pkvm_teardown_vm, __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_load, __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_put, + __KVM_HOST_SMCCC_FUNC___pkvm_tlb_flush_vmid, }; =20 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/h= yp-main.c index 32c4627b5b5b..130f5f23bcb5 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -389,6 +389,22 @@ static void handle___kvm_tlb_flush_vmid(struct kvm_cpu= _context *host_ctxt) __kvm_tlb_flush_vmid(kern_hyp_va(mmu)); } =20 +static void handle___pkvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1); + struct pkvm_hyp_vm *hyp_vm; + + if (!is_protected_kvm_enabled()) + return; + + hyp_vm =3D get_np_pkvm_hyp_vm(handle); + if (!hyp_vm) + return; + + __kvm_tlb_flush_vmid(&hyp_vm->kvm.arch.mmu); + put_pkvm_hyp_vm(hyp_vm); +} + static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ct= xt) { DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); @@ -573,6 +589,7 @@ static const hcall_t host_hcall[] =3D { HANDLE_FUNC(__pkvm_teardown_vm), HANDLE_FUNC(__pkvm_vcpu_load), HANDLE_FUNC(__pkvm_vcpu_put), + HANDLE_FUNC(__pkvm_tlb_flush_vmid), }; =20 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) --=20 2.47.1.613.gc27f4b7a9f-goog