From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-op-o11.zoho.com (sender4-op-o11.zoho.com [136.143.188.11]) (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 03169437467 for ; Mon, 13 Jul 2026 14:35:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.11 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783953319; cv=pass; b=LkaDtQ6MdugGBPTLkEYXz6UYT5y/jrCB21RHVCruScroGlEb+7GEInjtUo5t3VKir7HZVdAce32xjzwteMwbdXD6KI2+8TkK9QDGWsE1AKcgxUct+Yj6ccS5kWrlK78Dii9VbLBmkXDxYkZQE/ae5CmGohVBNWiDvHZFcX0C3iY= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783953319; c=relaxed/simple; bh=Fkim6C5ofoGrO2AlpvAXTsoLQpFE8yvDGzEzRjEn0r0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=A+CrLPbjI+JbD0zMhKFMZkmGgkIDms14kjnaWVRkCk0H2MdgxOcgFcIhQ3C0Ucq8nXQS9LwCr/y0s3HJsTkVMG+CR9i+l+bV6OGWjEOsyAaRlVni59stn6ZTSonmigtvWlCWcjabR/4kluYQ7vkfBJwn98UbUIPewe2iSNawYNE= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b=RwiSmt3s; arc=pass smtp.client-ip=136.143.188.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b="RwiSmt3s" ARC-Seal: i=1; a=rsa-sha256; t=1783953305; cv=none; d=zohomail.com; s=zohoarc; b=dtfwBb+KkqOk5LpS2l9XlY3Isr1cxSe4dyVL5LXR69Z6z6hzhLsQ+m6Y07qIuIS17sSwr/D1yxn8TWV+QxTy+IEpOglvePnj0u4uFfbxnFlGvGP47m7Zh8XlFdGD16tH+rePIikamDkj4VIfT8R2rq6qJTDeJR326ZA2cEPI4NY= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1783953305; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=Vt1ZxcDLSY0cCHvqeRxZcHXVOfGIWEo70HQ03fVvYCk=; b=AZGK5fCQYa6tk1H3Pvcm2xHvlkrhJVTPa6lPPkmtVxgW7BF3flDk03kkiXBIhXGeUtMRAEUQ31Ob3E6R+nWqHpSdHGCOOE78jDhBVuGdCgJCAYu95nz6y2JMJQGRUV6kyD/qc73/yGJZc1h/ZD6pvxUOUx/BlX8newOkg7nomNU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=dmitry.osipenko@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1783953305; s=zohomail; d=collabora.com; i=dmitry.osipenko@collabora.com; h=Message-ID:Date:Date:MIME-Version:Subject:Subject:To:To:Cc:Cc:References:From:From:In-Reply-To:Content-Type:Content-Transfer-Encoding:Message-Id:Reply-To; bh=Vt1ZxcDLSY0cCHvqeRxZcHXVOfGIWEo70HQ03fVvYCk=; b=RwiSmt3sorWaCVeer9aJuDH1LQXVyb8VzjGjVaZRnlvjljD7nuGEpWPmc0eghmr6 lmq2S6EmbamoRtgkK5hOhDRw19S2OOCZ8KX/fO1/q7FhSxsBAvdb2IgxcxoxW67tRHD hNpOiW12cxCm3iFze3vOjlv1rxrFCwCsOx1ELd4g= Received: by mx.zohomail.com with SMTPS id 1783953303349476.0443516936738; Mon, 13 Jul 2026 07:35:03 -0700 (PDT) Message-ID: <17764937-21dc-4b4a-8def-e738b361bcd1@collabora.com> Date: Mon, 13 Jul 2026 17:34:56 +0300 Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/3] drm/virtio: honor blob_alignment requirements To: Alyssa Ross , Sergio Lopez , Yiwei Zhang , Sergi Blanch Torne , Valentine Burley Cc: Chia-I Wu , Jason Wang , "Michael S. Tsirkin" , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , Xuan Zhuo , linux-kernel@vger.kernel.org, Simona Vetter , Thomas Zimmermann , David Airlie , Gurchetan Singh , Gerd Hoffmann , virtualization@lists.linux.dev, dri-devel@lists.freedesktop.org, Maxime Ripard , Maarten Lankhorst References: <20260428194450.518296-1-slp@redhat.com> <20260428194450.518296-3-slp@redhat.com> <87v7ajyw5j.fsf@alyssa.is> Content-Language: en-US From: Dmitry Osipenko In-Reply-To: <87v7ajyw5j.fsf@alyssa.is> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ZohoMailClient: External On 7/13/26 14:19, Alyssa Ross wrote: > Dmitry Osipenko writes: > >> On 7/1/26 14:10, Alyssa Ross wrote: >>> On Tue, Apr 28, 2026 at 09:44:49PM +0200, Sergio Lopez wrote: >>>> If VIRTIO_GPU_F_BLOB_ALIGNMENT has been negotiated, blob size must be >>>> aligned to blob_alignment. Validate this in verify_blob() so that >>>> invalid requests are rejected early. >>>> >>>> Signed-off-by: Sergio Lopez >>> >>> FYI: this change breaks crosvm, which is squatting the 5 and 6 values >>> of VIRTIO_GPU_F_* with different meanings. I've reported it as a >>> crosvm bug, so hopefully it can be taken care of there. >>> >>> https://issuetracker.google.com/issues/529852979 >>> >>>> --- >>>> drivers/gpu/drm/virtio/virtgpu_ioctl.c | 5 +++++ >>>> 1 file changed, 5 insertions(+) >>>> >>>> diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c >>>> index c33c057365f8..d0c4edf1eaf4 100644 >>>> --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c >>>> +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c >>>> @@ -489,6 +489,11 @@ static int verify_blob(struct virtio_gpu_device *vgdev, >>>> params->size = rc_blob->size; >>>> params->blob = true; >>>> params->blob_flags = rc_blob->blob_flags; >>>> + >>>> + if (vgdev->has_blob_alignment && >>>> + !IS_ALIGNED(params->size, vgdev->blob_alignment)) >>>> + return -EINVAL; >>>> + >>>> return 0; >>>> } >>>> >>>> -- >>>> 2.53.0 >>>> >> >> Thanks for the report. Indeed, crosvm will need to fix its experimental >> caps. CI will likely run into this problem first once it will update >> guest to 7.2+ kernel. > > I sent > https://chromium-review.googlesource.com/c/crosvm/crosvm/+/8064741 last > week but still waiting to hear anything. Do you have any insight into > whether it's still used / being pursued? The GUEST_HANDLE should be used by Android [1]. The FENCE_PASSING shouldn't be used in production, though don't know for sure. Crosvm should bump its experimental defines by +10 to prevent clash with upstream in future. [1] https://github.com/google/gfxstream/blob/main/host/vulkan/vk_decoder_global_state.cpp#L107 -- Best regards, Dmitry