From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.215.181 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794325566; b=MOcvigBZ6rEd8BQMDcjpYkLZRoyKeFlHruzMnaV1Lel33vF0B057eruSFoF1Jf9ods7j GAvqE7QXwDr+dvGSkkxFYzEUbko04no6szbKLe6AAm1SEVvmqJkbGFQtZnQc91uG6ZKyM 3ZdTZBfGj1vzcJZYJfYpxepnXxSEQZSaEFkV0Q4uoIn4blSoZVnZRPshIBaKF5tm8hZqI bUb+d3yu5VKFNK3cnV7Ors9ahgS9sIgW6kUJNNOYoeaeLpo04ahck57+b7WQ3nTL0rHvD lEybcOxNtSumMIcu8w8FH2k7jsP56iHT2A+34MuRIljtoZb0nDYxT+WIAMcXoZTkErQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794325566; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; bh=I6jvLVTJ6/L/P1TOo+cN1ccJTZcH95Jo/fx+GgYHa7w=; b=vMBhyEeQybmq++vL8QCPyxoQIANRSBEfVWta+pPJHouHJWlyUsjShYD1BbBHjcvBFXuF mWhL4sRsja6esJkJfg0VVEI1YzFKNbeKPl/4kVBJAoVaiIV5rfn/cDg9dBJTh6Ncw8pzf 1dIaming+0LfoZflxu4/907HsqkNjCOxAhlngDGh2eUg7DN0r1K8mmo0XRZBFiDuKUNv+ 2goZUH4eriaV7cvxyivrx/B7jzm/KuOYmLJUznA2Pk9wb+Ip99z/Dekg8VrGoFM3VDAYb b9FEwaSds6Zy8hVwLaT3EvuSew1ALY/kXYZYKhHBPVnMLuff0fOUaEEmstm50lA1bGA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass header.d=linaro.org header.i=@linaro.org header.a=rsa-sha256 header.s=google header.b="TxW0Z/LW"; arc=none smtp.remote-ip=209.85.215.181 Received: from mail-pg1-f181.google.com (mail-pg1-f181.google.com [209.85.215.181]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B17AB606AB75 for ; Tue, 10 Nov 2026 15:46:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B17AB606AB75 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.a=rsa-sha256 header.s=google header.b=TxW0Z/LW Received: by mail-pg1-f181.google.com with SMTP id 41be03b00d2f7-cd6acc50b8dso1013177a12.3 for ; Tue, 10 Nov 2026 07:46:05 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1794325565; x=1794930365; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=I6jvLVTJ6/L/P1TOo+cN1ccJTZcH95Jo/fx+GgYHa7w=; b=TxW0Z/LWuMJ4ao/uG9mGPMndIv5WC3u70B6uIi8rUgqnmcROMdn9Sl0bVRAXmI59M4 /AycfUqZ0pFWfuRkTZyWmAmLqaPNQXOX5W9WGgBiOlmkKsTPL6Sx1k0opbLsIDTni2XS CRCzdKwHbXTTEcJCNQ5liJoYpkajPt4r8MVPmNjLlZYQOPAEQggPHOCuZQDTNChULRor ahABAHl81KNf9V3L/ToxTodxcpB8GsRxYtHCwuYwsc7ex1IYkms0uwl7+Lwe9BoYdtc9 NtM3Jj9BI3qZC1OcYx1l9fBWEsd7CSF0dm4d6iGz7gQehCPciPKJyH5cn18rcMALAOQT k2AQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794325565; x=1794930365; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=I6jvLVTJ6/L/P1TOo+cN1ccJTZcH95Jo/fx+GgYHa7w=; b=PlMZbhiDZ+lfvFfKSVlM/y1euofe2yChF+Qog2S1gYGf8lbhSHHAcrsE53shaBXDCW TZJpE0HgfNTMJkZhOO1ua23nVRvZPmxpg3CXg42ruRkvKA0WwKl7FXtgqXV3BGcU9MeT KdYkXC7jjTc1pp5r/PEKpHt7F+4NEMDqxHzHpSquiOM81++7LSkvQdT3QXSIuwN4B8AD yu6bxJQ9RfmJGWX2+zZwNWRsmWOkbAhMKYi6tTehzblOtl2ppxReoZusZPTYve3PTeOx WJyz2V1ZQwtloHrsPg3niGwCZROhfPXfcPIPXxNxgW8JOG2mM6Kp13xsda1/uMmR/quV hNmA== X-Forwarded-Encrypted: i=1; AL+hErG8LU/B4dUQHHKpAU6TSVSWygB/h3VxA2dIfLjlt5KEnjEZ/Lr2VK01RdeK/Jqly7kFHwKunZuRBME=@vger.kernel.org X-Gm-Message-State: APuU4Z+349Bzuu5QRvBZlclNSw1qwhVkSMTfRIf/yW97bMjXpqkRlD25 FH3zjViOZREq5aXla162aEMaQl5t4UTv43np/k/u2Ke3jSpsrY+unc7JP3GXKJywMAQ= X-Gm-Gg: AYBFou3VqxVLdzUxMibI4aLXBUGidOrmZN97b75Jgb0lB0jqryjaDtv9YvVLi6JEsfo uUoK1ITJMDU7iJraiVKz3SlJxMgOEnCDmzq2nIInLtZOAC9BEDceILJc4X1whln7pS/hbnc2upT y4Zv5LABRl4SF8JBdVHaSmqg4dk/JiwaMvi2BHxApyoEatgUYaLm7RD+YrQFxidzl4oKXqecei/ hxy2zFnN6XhjQpwdiTZn81sYggcBQnVx+dzpKjh7E9Fc3WEMBYSEXTn54Jt2Ry+KSsAcdCQubhZ cWpQ+m3vsMj4yhhJyrdMJHvtMRPOAZpyiQT9DiaSpI248L8w6CUzFqJvkXUhf5nHrzXmz09Uc3C KGcvybcXd3ZeWE2fxIqjxJ0G2vdWd1lv+vPYrPl5cJRPZ4JGUdD5x2w3NkyXkJWRiM7EB7x5xj0 A6gOkwUxO/VesXzTMPB1BcPEW2AfX41rMOt8DcDQOJs0T9sOJrOv68Xpbjf1OjE+GIozeCbLlD0 5L/giVhlRRHhKqOpX9Zvy6hrknjjv1b+8x8UMcAO63ygygFRJPJl8RpYupikP1iB1i4QdgUwPHO SC0JeCz3iGDjOu8xXh5EQ50KUfpOOYa4tUPxyapdbo5ZkFQxxbaj5Q== X-Received: by 2002:a17:90b:57cf:b0:3b0:b64e:1e34 with SMTP id 98e67ed59e1d1-3b166ce8e72mr3333472a91.51.1794325564896; Tue, 10 Nov 2026 07:46:04 -0800 (PST) Received: from p14s ([2604:3d09:148c:c800:a917:5683:7f92:9eda]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3b17db2fcfesm325724a91.4.2026.11.10.07.46.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Nov 2026 07:46:04 -0800 (PST) Date: Tue, 10 Nov 2026 09:46:01 -0600 From: Mathieu Poirier To: Francesco Valla Cc: Bjorn Andersson , Kees Cook , "Gustavo A. R. Silva" , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Corbet , Shuah Khan , Randy Dunlap , Frank Li , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Peng Fan , Robin Murphy , linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH RFC v2 04/11] remoteproc: report VIRTIO_F_VERSION_1 for non-rproc-specific vdevs Message-ID: References: <20261102-remoteproc_virtio_map-v2-0-26b300e01c62@valla.it> <20261102-remoteproc_virtio_map-v2-4-26b300e01c62@valla.it> X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261102-remoteproc_virtio_map-v2-4-26b300e01c62@valla.it> Hi, I started reviewing this set, making it to this patch. I will continue tomorrow but due to the KVM forum later this week, I may not finish before next week. That said, I applied the first 2 patches so no need to include them in the next revision. Thanks, Mathieu On Mon, Nov 02, 2026 at 12:26:41AM +0100, Francesco Valla wrote: > There is currently no way to report the VIRTIO_F_VERSION_1 using the > resource table alone, as the per-vdev feature array is limited to 32 > bits. > > Considering that the VIRTIO 1.0 specification is now ~10 years old, > always report the VIRTIO_F_VERSION_1 feature for virtio devices that > are not specific for remoteproc usage. These latter, which as of today > are rpmsg and rproc-serial, are excluded to avoid impacting the existing > usecases, since VIRTIO_F_VERSION_1 changes the semantics of the > communication (e.g., the configuration space is assumed to be > little-endian rather than follow the device's endianness). > > While at it, replace BUG_ON() with WARN_ON() and return an appropriate > error in case of features that would overflow the 32 bits limit. > > Signed-off-by: Francesco Valla > --- > drivers/remoteproc/remoteproc_virtio.c | 28 +++++++++++++++++++++++++--- > 1 file changed, 25 insertions(+), 3 deletions(-) > > diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c > index c56d3330adfe..f1b362158a9c 100644 > --- a/drivers/remoteproc/remoteproc_virtio.c > +++ b/drivers/remoteproc/remoteproc_virtio.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -27,6 +28,11 @@ > > #include "remoteproc_internal.h" > > +static bool rproc_virtio_rsc_vdev_rproc_specific(struct fw_rsc_vdev *rsc) > +{ > + return (rsc->id == VIRTIO_ID_RPMSG || rsc->id == VIRTIO_ID_RPROC_SERIAL); > +} > + > static int copy_dma_range_map(struct device *to, struct device *from) > { > const struct bus_dma_region *map = from->dma_range_map, *new_map, *r; > @@ -268,8 +274,17 @@ static void rproc_virtio_synchronize_cbs(struct virtio_device *vdev) > static u64 rproc_virtio_get_features(struct virtio_device *vdev) > { > struct fw_rsc_vdev *rsc = vdev_to_rsc(vdev); > + u64 features = (u64)rsc->dfeatures; > > - return rsc->dfeatures; > + /* > + * All non-remoteproc-specific virtio devices are assumed to be > + * compliant with virtio specifications 1.x; there is no other method > + * to transmit this capability from the remote processor to the host. > + */ > + if (!rproc_virtio_rsc_vdev_rproc_specific(rsc)) > + features |= (1ULL << VIRTIO_F_VERSION_1); > + > + return features; > } > > static void rproc_transport_features(struct virtio_device *vdev) > @@ -285,6 +300,7 @@ static void rproc_transport_features(struct virtio_device *vdev) > static int rproc_virtio_finalize_features(struct virtio_device *vdev) > { > struct fw_rsc_vdev *rsc = vdev_to_rsc(vdev); > + u64 features; > > /* Give virtio_ring a chance to accept features */ > vring_transport_features(vdev); > @@ -292,8 +308,14 @@ static int rproc_virtio_finalize_features(struct virtio_device *vdev) > /* Give virtio_rproc a chance to accept features. */ > rproc_transport_features(vdev); > > - /* Make sure we don't have any features > 32 bits! */ > - BUG_ON((u32)vdev->features != vdev->features); > + /* Make sure we don't have any features > 32 bits except the expected ones. */ > + features = vdev->features; > + > + if (!rproc_virtio_rsc_vdev_rproc_specific(rsc)) > + features &= ~(1ULL << VIRTIO_F_VERSION_1); > + > + if (WARN_ON((u32)vdev->features != features)) > + return -EINVAL; > > /* > * Remember the finalized features of our vdev, and provide it > > -- > 2.56.0 >