From nobody Sat Oct 4 12:46:54 2025 Received: from out30-118.freemail.mail.aliyun.com (out30-118.freemail.mail.aliyun.com [115.124.30.118]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EB1FF26FA5E; Mon, 18 Aug 2025 05:42:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.118 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755495746; cv=none; b=fhcJUVPbsPg738GAuF2bgq4m6iGnVVYONJFOCrIXYtRXLqSEPp0L3LxYGrvv/5P0oVQ+X/T+d8qIjWteiSvDlj2jaM4yHUlmKKGoENFoHwmLWcP9weNPnB/0t9nDG43yA3twiGSDKSIb+H0v1ZJ/Nn+2haQ+HIGAzhfv10PprZY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755495746; c=relaxed/simple; bh=XExVPFjM+tFXne7pcUVaqjrlJWN5Mo3/9a3ND1Rmit8=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=eGge0zMPA5lHMAcA2+RIG3Rua6NImghvT5mjQ+vVYSXFwSpPsLUofmoiXufQs9ikBAuLfG5z8ApsfF1wKtmdCOx2sxirIlAeuR0K6kiQ1Mo8GjKZT1vGPbAmNovECwei1kkoFt17/2zjlJh/L5hnsJNU6lbpXNMu70tHghoJpIc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=hPIwl/x4; arc=none smtp.client-ip=115.124.30.118 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="hPIwl/x4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1755495734; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=W4lHP3UjuHeCBUcDEIF9ZeVamIkRm6NrjeDmREzHBUM=; b=hPIwl/x466LMKdD2zsBK0SqUCtPuPve8LARSTo62NI9PQqaVxjM8k5nih0mUEbv/1RcV2gs18W9L+S0P8GQi7JFfDwCgyaraHjPkBm93TefAKdtiD4j1WV/whZ3GDR8O9tuK0/GL8rHfKMYSG5k17coXXv52LIoCHCfXk/67ArQ= Received: from localhost.localdomain(mailfrom:fangyu.yu@linux.alibaba.com fp:SMTPD_---0Wlvjb0u_1755495732 cluster:ay36) by smtp.aliyun-inc.com; Mon, 18 Aug 2025 13:42:14 +0800 From: fangyu.yu@linux.alibaba.com To: anup@brainfault.org, atish.patra@linux.dev, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr Cc: guoren@linux.alibaba.com, guoren@kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Fangyu Yu Subject: [PATCH V2] RISC-V: KVM: Write hgatp register with valid mode bits Date: Mon, 18 Aug 2025 13:42:07 +0800 Message-Id: <20250818054207.21532-1-fangyu.yu@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Fangyu Yu According to the RISC-V Privileged Architecture Spec, when MODE=3DBare is selected,software must write zero to the remaining fields of hgatp. We have detected the valid mode supported by the HW before, So using a valid mode to detect how many vmid bits are supported. Signed-off-by: Fangyu Yu Reviewed-by: Guo Ren Reviewed-by: Troy Mitchell --- Changes in v2: - Fixed build error since kvm_riscv_gstage_mode() has been modified. --- arch/riscv/kvm/vmid.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c index 3b426c800480..5f33625f4070 100644 --- a/arch/riscv/kvm/vmid.c +++ b/arch/riscv/kvm/vmid.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include =20 @@ -28,7 +29,7 @@ void __init kvm_riscv_gstage_vmid_detect(void) =20 /* Figure-out number of VMID bits in HW */ old =3D csr_read(CSR_HGATP); - csr_write(CSR_HGATP, old | HGATP_VMID); + csr_write(CSR_HGATP, (kvm_riscv_gstage_mode << HGATP_MODE_SHIFT) | HGATP_= VMID); vmid_bits =3D csr_read(CSR_HGATP); vmid_bits =3D (vmid_bits & HGATP_VMID) >> HGATP_VMID_SHIFT; vmid_bits =3D fls_long(vmid_bits); --=20 2.49.0