From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792680140; b=SRvDlcJaa/4J9QK/8gCXo9Y3xIjLg4OnSlYmOyoEniWwshfC7Woe+tpAkglMI8kGCphC DxskkuFo42kMsFrgROzQBxNOrwAe5zpRM5nWNZsL6AgqI3Vo6hpaLofwB5lIxJn7IzfXW x/ao2IgiPvuRFqHLvGUQMWrxlyLsyw3eY06qHoJDSMw8tHKW86PYVqY3QjLjEW2qm8U7C 9suCqC9zbgUTPBw9uiSTbg3xU4yUuBuJQbvvCd3ahglnws1mH5HVtWNKenZ0FTLAZoLhE VH2V7V5MUpsptuPjUW5yX6nUA2QMfV3v8qHizjumFtDhIr7VU7cXTnZsJ3d44YvIdYQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792680140; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=Y/LUBFBKFZ6pOnoBKgntXD5HdgzoU+tx/ippvDPRFz8=; b=XosuQmf5vH2HQOxXXqXsWLXWITqnbrxofaWrytTSdtfhq/DGBZCtccsFhIEzWOp0+R12 dJJayXPXk0xA9btaPH2Li43hxXM1s23Pt1wHxYPSOpykA+JCE1g7OKuiAFbQkqwxix/9x MPTH1Ds9nvwQf/+izF5cUIenIxDIR9EdB2wqoCX1fMA7yDMCOhwNn0ay105sCxMA0x6KG crYFzX4NBAlrvhbLKtwRXKXvOkg7ukmIqgGOkxjp10UvamIiRPevU764lH3P55Mg5kFoR xY+GyYi7scNJ3C/Co9qAsf/eIwjvBLu24Hl3wPxPT8WJLzAWtH/yck7xNzT8yiSDpvg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QwWnv18G; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E2BAA606A319; Thu, 22 Oct 2026 14:42:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QwWnv18G Received: by smtp.kernel.org (Postfix) with ESMTPSA id E5D1F1F000C1; Thu, 22 Oct 2026 14:42:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792680139; bh=Y/LUBFBKFZ6pOnoBKgntXD5HdgzoU+tx/ippvDPRFz8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QwWnv18GDdspYldAzA7jwq1orZiwP7kwD51CJLmUI/hA7JOIigj13YSsCGdmecAvc 46Af8XgaSPB0/af488hSXMzWXBZVYhz8feqjz6tYcWXLwhnafFM9RDkg39VH8qCo88 5tE9J8PdRTbOpIYqlb8uDjAZ2Qj03gqPOknl6+GfjnlxGEq5DXEWXRPg4qsEq/kJ1A ud1/u0zwCXeBpft9qDuksliQChVPjBmBY9KSWVHGjLckqW6imzLu9eXF3Kd3bwkWip 9qq4z16OLDLz4mvuBRQYs+8RF3hME3KlSwqBioPcsuHFFkBOcWurQkDU9bXbu0ZLSs 7REL9rmOdlKLQ== From: Sasha Levin To: Paolo Bonzini , Anup Patel Cc: Mark Brown , Lorenzo Stoakes , Marc Zyngier , Jinyu Tang , Atish Patra , Palmer Dabbelt , Paul Walmsley , Albert Ou , Alexandre Ghiti , kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-next@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] KVM: riscv: Implement kvm_arch_pre_fault_allowed() Date: Thu, 22 Oct 2026 10:42:16 -0400 Message-ID: <36adc119db9b30984c0df4d1846c0f29e4e46c07.1792679974.git.sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: References: X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Commit caa63620f9e3 ("KVM: Allow architectures to disallow pre-fault") requires every architecture that selects KVM_GENERIC_PRE_FAULT_MEMORY to implement kvm_arch_pre_fault_allowed(), and there is no generic default. Commit e8b32e377951 ("KVM: riscv: Implement KVM_PRE_FAULT_MEMORY") was written before that hook existed, so it selects the option without implementing the hook. With both commits in the same tree, riscv builds with KVM enabled fail to link: ld.lld: error: undefined symbol: kvm_arch_pre_fault_allowed >>> referenced by kvm_main.c >>> virt/kvm/kvm_main.o:(kvm_vcpu_pre_fault_memory) in archive vmlinux.a The riscv implementation does not refuse pre-faulting in any state, so return 0 to keep its current behaviour. Fixes: e8b32e377951 ("KVM: riscv: Implement KVM_PRE_FAULT_MEMORY") Signed-off-by: Sasha Levin --- Paolo, this is needed when kvm-riscv-7.4-1 is merged into kvm/next. Feel free to squash it into the merge instead. Mark, next-20261022 already fails to link, so linux-next needs this on top of the kvm-riscv merge. Build-tested with a riscv tinyconfig plus KVM=y on next-20261022 and on kvm/next with kvm-riscv-7.4-1 merged. Not runtime tested. arch/riscv/kvm/mmu.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c index e8673cfa69668..738d9ee1eac9d 100644 --- a/arch/riscv/kvm/mmu.c +++ b/arch/riscv/kvm/mmu.c @@ -754,6 +754,11 @@ int kvm_riscv_mmu_map(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot, return ret; } +int kvm_arch_pre_fault_allowed(struct kvm_vcpu *vcpu) +{ + return 0; +} + long kvm_arch_vcpu_pre_fault_memory(struct kvm_vcpu *vcpu, struct kvm_pre_fault_memory *range) { -- 2.53.0