From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 D9BBB409621 for ; Mon, 15 Jun 2026 16:22:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781540529; cv=none; b=IigE5eE3x8CIgR7drhg/nLGg94oL9PSLdyX4ayTeWu10HLHyObp87KVsX3IHxs8/t88V1E3VBeKZVJ1oG8xkS265NcWpAGXcGvLNBMviB1r+oNqOUL4a4f0taPNrcCJl48XmDN9wOij0EFojFZmvhBzOYN38yllKT+eV145Olxw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781540529; c=relaxed/simple; bh=a5VPlCIfw73AxC2UWjalKClT1VYDWEVRJ5q6XeibAdo=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=nFL1BQRHr7JEPC+PdiAnjnoo2zh/dd17iqLBak3b/F7XcFVRBzIMzvvn3QVNQoQRniHnfql3WSge/AU4ciAeWjsDOBbekx06rAS7/j59C3kjM7SXYfHLM6LVvWP+HJENEAwUCyrEqqlvQ9j2HZrV/G/yXnefp1YX7k1VDqQeXI4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Ta7h7vO/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Ta7h7vO/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E55BD1F000E9; Mon, 15 Jun 2026 16:22:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781540528; bh=b95s2aau7bKrvjS1kyT8QnRyDF5VgDd3NuEMutyHXU0=; h=Subject:To:Cc:From:Date; b=Ta7h7vO/d/MP9yaGMy/DelxYbOAh43TA+Apqr/CMnMxKQihEtz1teHw4qlKXazzDJ 7MquujPJkM9TURDLB8Tr2bZrGCWptyAxqUNKUMT1v+lxOPzJUhUR0TieirRGJDN1AY uBErL7wNi0pTqJbCygp4H/nlp0gd/H4xQk5w6EQU= Subject: FAILED: patch "[PATCH] drm/v3d: Skip CSD when it has zeroed workgroups" failed to apply to 5.10-stable tree To: mcanal@igalia.com,itoral@igalia.com,jmcasanova@igalia.com Cc: From: Date: Mon, 15 Jun 2026 18:01:30 +0200 Message-ID: <2026061530-phoniness-operative-8a96@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 7f93fad5ea0affc9e1505dd0f7596c0fdb496213 # git commit -s git send-email --to '' --in-reply-to '2026061530-phoniness-operative-8a96@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 7f93fad5ea0affc9e1505dd0f7596c0fdb496213 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ma=C3=ADra=20Canal?= Date: Tue, 2 Jun 2026 14:50:15 -0300 Subject: [PATCH] drm/v3d: Skip CSD when it has zeroed workgroups MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit A compute shader dispatch encodes its workgroup counts in the CFG0..CFG2 registers. Kicking off a dispatch with a zero count in any of the three dimensions is invalid. First, the hardware will process 0 as 65536, while the user-space driver exposes a maximum of 65535. Over that, a submission with a zeroed workgroup dimension should be a no-op. These zeroed counts can reach the dispatch path through an indirect CSD job, whose workgroup counts are only known once the indirect buffer is read and may legitimately be zero, but such scenario should only result in a no-op. Overwrite the indirect CSD job workgroup counts with the indirect BO ones, even if they are zeroed, and don't submit the job to the hardware when any of the workgroup counts is zero, so the job completes immediately instead of running the shader. Cc: stable@vger.kernel.org Fixes: d223f98f0209 ("drm/v3d: Add support for compute shader dispatch.") Suggested-by: Jose Maria Casanova Crespo Reviewed-by: Iago Toral Quiroga Link: https://patch.msgid.link/20260602-v3d-fix-indirect-csd-v4-2-654309e32bc0@igalia.com Signed-off-by: Maíra Canal diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c index 47f83936cd73..8a635a9ec046 100644 --- a/drivers/gpu/drm/v3d/v3d_sched.c +++ b/drivers/gpu/drm/v3d/v3d_sched.c @@ -352,6 +352,16 @@ v3d_csd_job_run(struct drm_sched_job *sched_job) return NULL; } + /* The HW interprets a workgroup size of 0 as 65536; however, the + * user-space driver exposes a maximum of 65535. Therefore, a 0 in + * any dimension means that we have no workgroups and the compute + * shader should not be dispatched. + */ + if (!V3D_GET_FIELD(job->args.cfg[0], V3D_CSD_QUEUED_CFG0_NUM_WGS_X) || + !V3D_GET_FIELD(job->args.cfg[1], V3D_CSD_QUEUED_CFG1_NUM_WGS_Y) || + !V3D_GET_FIELD(job->args.cfg[2], V3D_CSD_QUEUED_CFG2_NUM_WGS_Z)) + return NULL; + v3d->queue[V3D_CSD].active_job = &job->base; v3d_invalidate_caches(v3d); @@ -402,13 +412,13 @@ v3d_rewrite_csd_job_wg_counts_from_indirect(struct v3d_cpu_job *job) wg_counts = (uint32_t *)(bo->vaddr + indirect_csd->offset); - if (wg_counts[0] == 0 || wg_counts[1] == 0 || wg_counts[2] == 0) - goto unmap_bo; - args->cfg[0] = wg_counts[0] << V3D_CSD_CFG012_WG_COUNT_SHIFT; args->cfg[1] = wg_counts[1] << V3D_CSD_CFG012_WG_COUNT_SHIFT; args->cfg[2] = wg_counts[2] << V3D_CSD_CFG012_WG_COUNT_SHIFT; + if (wg_counts[0] == 0 || wg_counts[1] == 0 || wg_counts[2] == 0) + goto unmap_bo; + num_batches = DIV_ROUND_UP(indirect_csd->wg_size, 16) * (wg_counts[0] * wg_counts[1] * wg_counts[2]);