From nobody Tue Feb 10 06:04:54 2026 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 DD4EB20FAA7 for ; Mon, 16 Dec 2024 17:58:40 +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=1734371922; cv=none; b=dsjSIKOxE0/n2txf0ChXRg+67DAVcCpg2Mn3bWpijgCJf9+4vTVuqURxsL60/MyKqx+Mq2j9MO3WJ2KKRLzV8SH7mVvk766vRFeXVFoOKgD8sZcj82Uvf2MApqnPKdFxZLZTDayb0rQHm5v814MKIZMvcq277+Glg6n6gaM0dTA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734371922; c=relaxed/simple; bh=S5C7PA49mbBbYP0VC8WHfs83VKenKobir8rsTzZpXTE=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=kPij2P5WuBLsgQVmKIPl+AtpQVbOZGlk0ve8+q6BZdehf06IqKB+1qZmaZMMrwSst+tlZKOMt/0yAtf5sj3F5guQjmYzmNY+B6PKfW0uTQJ4y9gUbsZp4N/TlUarG6upuEXpeu/WQekS30sTEqoOY7GH+3Dkrw9rVjjW7w8HBYY= 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=0zXVX60f; 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="0zXVX60f" Received: by mail-ed1-f73.google.com with SMTP id 4fb4d7f45d1cf-5d3cef3ed56so3931308a12.1 for ; Mon, 16 Dec 2024 09:58:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1734371919; x=1734976719; 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=vLkxU7WF3J5Qh0Edw4/qg3eGiYkLZ2iXz4JSY5pi8io=; b=0zXVX60fzBTtnMLd4lvPJroPPfiIpJb6ZD6zMOphw5jhPpPeJH5de+O8tUq1UQawIr ZOpR0HuiGKv7pVf2lShNBk0eFVvQ6DL8eaJCQ/S0xjxn51BHuNV46ahYp/p6kTt7zJ04 EBHs8/z5CaEFOWl70mi7R0fJ179Hcw1HdgLGH2Injf1a4qrbJGo+lipHKO7gezslFMi0 Ji75ywrbp4wKUpXxdP+EVCxxhpjDDJWPyGOX6mybDjnFXtKMWMs+Dl9wvQFmcuUNFelc h1FepcWTja/MOWxkYoKVR3gFDC196d0umWC/WBcFDkYkFnyxqQcUEsDepxpl21+Do42Q dUyQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734371919; x=1734976719; 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=vLkxU7WF3J5Qh0Edw4/qg3eGiYkLZ2iXz4JSY5pi8io=; b=gnuv4ZG0w2oDAZbiVag6+ZzZYMWst8msM229myYrEBO3XURa1naaDadFvvgW2UOwaD Pg7iaDQBazRiSOzWBoAoJhE/YtqhDJQdBOibEWe/S44ZE02mi2xWqBSBlqzNsZR8zE2a RAK8wcVG0+aDwC1rjpa845Grz0RpwHlhT2M9hepMzSPMIWM8w8q0f3trEzzJp1LSx4Da Os5YkjTFvMcEcDIQQ8Vx/lg91poi7cHB5UJOeGyh4uxLr/C45mA0S5WwKlrrJ/DqRzkR /SEIL1mBHY2WoHq5o5QAkJ3gots5nXA7lyGY+kysh00UEk9hSna666CPVyfwYomhbIrW bIDQ== X-Forwarded-Encrypted: i=1; AJvYcCU8coiq0/udkr8fPXaFHfPBnW2r3w6ZLKlQwUvgT7SHrdrYpugggTFEOd7Kiz3iUt/ZUmQgLkC1yqCb0oM=@vger.kernel.org X-Gm-Message-State: AOJu0YzEU+/oDzUsaaUUjASCi0NsrO8m+Mz9CvxGBwG7iZNa3/cmMSBh PbUQ3sAninooZVLDuMVyYFmc43lHB747f97zja+xH8B2TnD2wNRaaJINXLvEOJPYNK+zqt/31zz gCmgTqQ== X-Google-Smtp-Source: AGHT+IGbIEoG5vbn6iQy08UEUu36i7r1jxdCnom039llyQo30KhKhUU2a+YhuuCdj1YaRdinsIVQTfjkxghQ X-Received: from edvu14.prod.google.com ([2002:a05:6402:110e:b0:5cf:ca3f:365]) (user=qperret job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:2807:b0:5d0:d610:caa2 with SMTP id 4fb4d7f45d1cf-5d63c3ad29cmr12773175a12.26.1734371919408; Mon, 16 Dec 2024 09:58:39 -0800 (PST) Date: Mon, 16 Dec 2024 17:58:01 +0000 In-Reply-To: <20241216175803.2716565-1-qperret@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241216175803.2716565-1-qperret@google.com> X-Mailer: git-send-email 2.47.1.613.gc27f4b7a9f-goog Message-ID: <20241216175803.2716565-17-qperret@google.com> Subject: [PATCH v3 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. Signed-off-by: Quentin Perret Reviewed-by: Fuad Tabba --- 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