From nobody Tue Feb 10 20:30:49 2026 Received: from mail-pl1-f171.google.com (mail-pl1-f171.google.com [209.85.214.171]) (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 752431D90B3 for ; Wed, 15 Jan 2025 18:31:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.171 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736965866; cv=none; b=VqX3r2m59xDHemdYIY9hBW2Lf31S47m+oR9jbvDwbWZlbRbeWa78KadpJJatj+/ygtecWh8knx+ZavkMouxsjMZ/NrjkIaVkoq+VOSxuYQvxDbbanrepiNskm6Exzsw3rzT8yg0drW+JRIDswkcz17/We+txP2qLQxIyt75McXc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736965866; c=relaxed/simple; bh=2VZE7ahRiWFyeef1RfOaScKQMn6RmpORm+fo0poup2k=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=LxMCYDlDwvlsAppIoFgYVxM2aPiTs44n0fILYKyKfU+ftIGp35lpsx9i2vy5qtPMgijBvZ6GiwGKYiDG1v8WWYW+ETKP6NRwo+m95RB05f+dZv1ddLR/oMNOEZ+mV5sA9inl/MP0MGvtC2/QhJhU3SUJhln8AQ16dQi1Y7FKbpw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com; spf=pass smtp.mailfrom=rivosinc.com; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b=nkWp8jfH; arc=none smtp.client-ip=209.85.214.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rivosinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rivosinc-com.20230601.gappssmtp.com header.i=@rivosinc-com.20230601.gappssmtp.com header.b="nkWp8jfH" Received: by mail-pl1-f171.google.com with SMTP id d9443c01a7336-21661be2c2dso127640015ad.1 for ; Wed, 15 Jan 2025 10:31:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1736965864; x=1737570664; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=eGsO74qlfZsPi9kGTe6Mf3rItgKav5O5SJKk6N7d7+Y=; b=nkWp8jfHWt38tCi3A89AHaGElaPgfNyRMPfRv4RhE9DWQIIIeR1W4OmpSHrz4EbW6y Bqh7GxEOYJ8l7iKj9oVom+0EqYn6XaJ8/+gQfXiEaXuQ4uM7FHu1CP9RTolrfYDjj5AY VSDKg9JSdqeB6stLmPAMMvft+eHpBIObRSzVJC2PLMPYABIOQ06R5Zv9iKD/pt2C3jLW 1zUgcs7HG1j78dLCh/adaE1LF9ZJ1tsXKNCOwL5U9XaECPxxlPyTnpS6Vs3LLCFEECgx wJxEsGZNnILHRGsLPP3nO6X1m6+i8ZVxFj75POG0gDH4cfxNt0tc69Q4bxV2QdqpGZgW 5X0Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736965864; x=1737570664; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=eGsO74qlfZsPi9kGTe6Mf3rItgKav5O5SJKk6N7d7+Y=; b=Nef1phgoltRIqAv35WjzoXchtdilw/QcykT/S/UoQEMzlBlDLUd4j35BvNb3nKYyDy ZSuwS2sCATwt04Uw5FwF94ncbs2+gG1N+RMQuu7WmFfkS74/XhNzRBb7MLq33dKOKtF/ 819PscXZ2rg9KFX3LDyLYcP9JvOxOShw0nYS/6rrvmvgGwvFnLE5F5At9h1cImWhyJmf XdBn+o+cqE58rMLs8GKrlU+EG4JXXeanRdwK8k6u6tkq4wombzZ/7IRsJnWMaPZSU2Yw b481rsIt8LgeHMSLz8RsDFmVs/IcKOIpyvNThMy3vX6zVbqfhDfmXWkBDTPjCviomloQ JtDA== X-Forwarded-Encrypted: i=1; AJvYcCVHgZeNakT9rzBpwrKbjVFFBT4LKt53y3xY98jmDkza+rNOKvcJeovT4TVnOac5Ahi2KxFDHK5Y3GgzWeI=@vger.kernel.org X-Gm-Message-State: AOJu0YznrTjJoQg+eP4jJsgdNNsqTr3YkaZA9sLglFV2L0O5uh1gpf/0 LRa/e9U8pFKz0oPXeHEUqU/yPRcrnHI7kbt1yqXrJue5wRDOiWTCtl+dL5+0+LpkiRnYXxORvUB X X-Gm-Gg: ASbGncs3x1Lods78xqrNeE1LMROlMcrBec6YAMvu7dKodV3GIKbai8w1OT0MiRKjmHH Nnb9HasOOClFxWXhQWnGdMvh/F+8dErolz51RFyi2zwlEBq0uQU/Gtfc4MQtFn9QbUPJ0ldSjc9 JuTpZU8kklBkDekLlGyg1MxX2uEt++HdRyd6sUgdShAEcYn/1FUF6dpA1Mpxh9CPmcp4C5zOfwI wrpYXWn8f8R9DAH0g08P8rz6JB8vls1SVXAWNEg5kCwYKBELjuutzQHX3VTaxaUbsTfvw== X-Google-Smtp-Source: AGHT+IEVuy0zAtOEk7axH9BqkY46Q1CUJK/CsgMJYOIS0qmHtHOLlyWCGQnQHM7bf0KJ01YfA5xjlQ== X-Received: by 2002:a17:902:cccb:b0:216:6769:9eca with SMTP id d9443c01a7336-21a83fd35bdmr452990815ad.37.1736965862343; Wed, 15 Jan 2025 10:31:02 -0800 (PST) Received: from atishp.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21a9f219f0dsm85333195ad.139.2025.01.15.10.31.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jan 2025 10:31:02 -0800 (PST) From: Atish Patra Date: Wed, 15 Jan 2025 10:30:46 -0800 Subject: [PATCH v2 6/9] KVM: Add a helper function to validate vcpu gpa range Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250115-pmu_event_info-v2-6-84815b70383b@rivosinc.com> References: <20250115-pmu_event_info-v2-0-84815b70383b@rivosinc.com> In-Reply-To: <20250115-pmu_event_info-v2-0-84815b70383b@rivosinc.com> To: Anup Patel , Will Deacon , Mark Rutland , Paul Walmsley , Palmer Dabbelt , Mayuresh Chitale Cc: linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Palmer Dabbelt , kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, Atish Patra X-Mailer: b4 0.15-dev-13183 The arch specific code may need to validate a gpa range if it is a shared memory between the host and the guest. Currently, there are few places where it is used in RISC-V implementation. Given the nature of the function it may be used for other architectures. Hence, a common helper function is added. Signed-off-by: Atish Patra --- include/linux/kvm_host.h | 2 ++ virt/kvm/kvm_main.c | 21 +++++++++++++++++++++ 2 files changed, 23 insertions(+) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 401439bb21e3..d999f80c7148 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1363,6 +1363,8 @@ static inline int kvm_vcpu_map_readonly(struct kvm_vc= pu *vcpu, gpa_t gpa, =20 unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn); unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, b= ool *writable); +int kvm_vcpu_validate_gpa_range(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned= long len, + bool write_access); int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,= int offset, int len); int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa, void *dat= a, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index de2c11dae231..b81522add27e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3283,6 +3283,27 @@ int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_= t gpa, const void *data, } EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest); =20 +int kvm_vcpu_validate_gpa_range(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned= long len, + bool write_access) +{ + gfn_t gfn =3D gpa >> PAGE_SHIFT; + int seg; + int offset =3D offset_in_page(gpa); + bool writable =3D false; + unsigned long hva; + + while ((seg =3D next_segment(len, offset)) !=3D 0) { + hva =3D kvm_vcpu_gfn_to_hva_prot(vcpu, gfn, &writable); + if (kvm_is_error_hva(hva) || (writable ^ write_access)) + return -EPERM; + offset =3D 0; + len -=3D seg; + ++gfn; + } + return 0; +} +EXPORT_SYMBOL_GPL(kvm_vcpu_validate_gpa_range); + static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots, struct gfn_to_hva_cache *ghc, gpa_t gpa, unsigned long len) --=20 2.34.1