From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (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 D14A83C3797; Wed, 13 May 2026 09:10:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778663431; cv=pass; b=Dn6iZt+rSILYQ1tUaBQn8C+wZsDB86S5UoRjhtmDILUV1j2A5X3q7NwvxzTmrXyoR4T6lU6ZiZjrxHN/svm7N+r27X5q5zsRKK1e0FXCWi/QUvvYPAoaOm8986G0VssYj9wypqz2tHcBvEk0iIcjZVldcNU+Cbbev01FJuwPiqE= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778663431; c=relaxed/simple; bh=BCkN3CWqi1Fou1vJgclLldEXybnXWRswFik3LuSrcf0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=rE5RO7oKRKuMMy/jGsewYoqTJruz0Smk6qVdQQlxbVn7Vwf2bpeXgbwWQYhNDVnFHUzS/w5brqCFFI9NItyejqG4cpxjuuREnA87xuLrjFIfzMq8NUN+qHqOiVvlvC18Djqj5WqNR4PXLE3BZ9GrZqXb2QCPsnos+c7ttUt4gVY= 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=Jf8V2eOO; arc=pass smtp.client-ip=136.143.188.112 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="Jf8V2eOO" ARC-Seal: i=1; a=rsa-sha256; t=1778663410; cv=none; d=zohomail.com; s=zohoarc; b=fKPVwADO8NoII5QZA/9nW44lDanjOSOPhHM423Zx+9+6zesDGOnMff+bl6Rvh35UgZazW4f6pUAJvbXAvKHqhZZYFdnmRXBF06iR1kPcV68F6IKn45f8ugIZ8e4PJ7XblV87S1FasZpuW7NarX5/YHkLXMUQ3iWeg5UVpuMhmHg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1778663410; 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=J+PeEpwgMGG+eT1L4WzFjaLfRNxviLWx3M2E/85kEME=; b=LWW9GtphE/fmKFD55IBBhxIMs4RggAQDNovGJ63G4XWnycQHO5zTbncfVhvn8bBHggKZZUhjQBOziPDbusIDx0usWV5F4GoxPV1yeIwUdB2LfIsVfiVpUaDZZ/xiaJLbZ2XE1NyxxM9w+i2ohLfDSfrQe3cfbQ6JjUt4B1rCsRQ= 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=1778663410; 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=J+PeEpwgMGG+eT1L4WzFjaLfRNxviLWx3M2E/85kEME=; b=Jf8V2eOOgD0CHQN4V+0lESC/eA0s1LNDholC2vph3WSKS4d0gSXu+TJW0UbFGg89 A/7jUvEcwwmIPXG2OJJQZoQi/h3CGidnrHf3CfQCPBsxoautZJNHcFBo8FbSwEEvaZW E4WUHbJwdUDYlCgS0OJ9jhB9OvEW+ZhL6xqB/ifM= Received: by mx.zohomail.com with SMTPS id 177866340828668.99618190513445; Wed, 13 May 2026 02:10:08 -0700 (PDT) Message-ID: <65da2ce9-a2ab-4800-a73e-1a26082d0605@collabora.com> Date: Wed, 13 May 2026 12:10:02 +0300 Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] drm/virtio: move cursor resv lock acquisition to prepare_fb To: Deepanshu Kartikey Cc: airlied@redhat.com, kraxel@redhat.com, gurchetansingh@chromium.org, olvaffe@gmail.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, simona@ffwll.ch, sumit.semwal@linaro.org, christian.koenig@amd.com, dri-devel@lists.freedesktop.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, syzbot+72bd3dd3a5d5f39a0271@syzkaller.appspotmail.com, stable@vger.kernel.org References: <20260512020718.108044-1-kartikey406@gmail.com> Content-Language: en-US From: Dmitry Osipenko In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ZohoMailClient: External On 5/13/26 04:55, Deepanshu Kartikey wrote: > On Tue, May 12, 2026 at 12:04 PM Dmitry Osipenko > wrote: >> >> I'm getting lockup with this patch applied and now see that >> virtio_gpu_resource_flush() also locks BO. >> >> Easiest option might be to add uninterruptible variant of >> virtio_gpu_array_lock_resv(). Could you please try it for v3? >> >> -- >> Best regards, >> Dmitry > > Hi Dmitry, > > Thanks for testing and catching the lockup. Before I send v3, want > to confirm the approach: > > 1. Revert v2's prepare_fb / cleanup_fb / plane_state changes; > keep the lock acquisition inside cursor_plane_update like > the original code. > > 2. Add virtio_gpu_array_lock_resv_uninterruptible() in > virtgpu_gem.c, mirroring the existing helper but using > dma_resv_lock() instead of dma_resv_lock_interruptible() on > the nents==1 path. Declare it in virtgpu_drv.h. > > 3. In cursor_plane_update, call the new helper and check its > return. The signal path is closed; -ENOMEM from > dma_resv_reserve_fences() remains and is handled by freeing > objs and skipping the cursor update for that frame. > > A skipped cursor frame on ENOMEM is the remaining failure mode in > .atomic_update; this avoids the lockup with virtio_gpu_resource_flush() > that v2's broader lock scope caused. > > Does that match what you had in mind? Sounds good. The virtio_gpu_resource_flush() also should be updated to use uninterruptible() variant. -- Best regards, Dmitry