From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 F1031181CE1; Sun, 1 Sep 2024 16:31:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725208283; cv=none; b=k/D4sZ/flCBw7z2TMY4bgfBQOPtcndk1KhSvUkqDK4YqlkVkcf7wf/QqG2gMFrLD1mzecHbsqbYsHc4TZSZ1REQrCfXqK8gUOLaFaKaaLPcHnkrVOy6oC+xrh1PZY3uWtCosCIjpYOSpedTRowgbME5KBU419p31qWnEHQlESPg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725208283; c=relaxed/simple; bh=wWhDUtQWEEc59DnKnsPBWImRYCR/lCLBlJyYpyFRhKc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=acL2aaIESZyLAwryQMyDabXQpXVJPvExuCKKUMnp5mgB71oLgoUYSZV1WwcKowARky4zUGPc1C9IpQaDlM3PLZF9nS6Oqw7mRkv9Y0wd1hN1H3qAavhjpW1BeBRPljl9ffHhi7uSICypH3igdMJyyYboC4XwXOIlbtMSg6MgDTY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jSCcNHlG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jSCcNHlG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E55AC4CEC3; Sun, 1 Sep 2024 16:31:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1725208282; bh=wWhDUtQWEEc59DnKnsPBWImRYCR/lCLBlJyYpyFRhKc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jSCcNHlGnaKcbGh9gJKhpvZ+QIio07PGvvj73JM5JMT7ghjE2JfgEw/fmaqBvEUiu RoNQwihVlwv9xvZCXiXNHcZw87aIAYd81cYJ/E7d/29kCRsRKaP/+PFqdWTd9OsvCk 7n1AQeHCk2zruB4zhfa90FOyqcL/3Ad+0/bfpbFo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Ma=C3=ADra=20Canal?= , Tvrtko Ursulin Subject: [PATCH 6.10 035/149] drm/v3d: Disable preemption while updating GPU stats Date: Sun, 1 Sep 2024 18:15:46 +0200 Message-ID: <20240901160818.782119823@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240901160817.461957599@linuxfoundation.org> References: <20240901160817.461957599@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore 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 6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tvrtko Ursulin commit 9d824c7fce58f59982228aa85b0376b113cdfa35 upstream. We forgot to disable preemption around the write_seqcount_begin/end() pair while updating GPU stats: [ ] WARNING: CPU: 2 PID: 12 at include/linux/seqlock.h:221 __seqprop_assert.isra.0+0x128/0x150 [v3d] [ ] Workqueue: v3d_bin drm_sched_run_job_work [gpu_sched] <...snip...> [ ] Call trace: [ ] __seqprop_assert.isra.0+0x128/0x150 [v3d] [ ] v3d_job_start_stats.isra.0+0x90/0x218 [v3d] [ ] v3d_bin_job_run+0x23c/0x388 [v3d] [ ] drm_sched_run_job_work+0x520/0x6d0 [gpu_sched] [ ] process_one_work+0x62c/0xb48 [ ] worker_thread+0x468/0x5b0 [ ] kthread+0x1c4/0x1e0 [ ] ret_from_fork+0x10/0x20 Fix it. Cc: Maíra Canal Cc: stable@vger.kernel.org # v6.10+ Fixes: 6abe93b621ab ("drm/v3d: Fix race-condition between sysfs/fdinfo and interrupt handler") Signed-off-by: Tvrtko Ursulin Acked-by: Maíra Canal Signed-off-by: Maíra Canal Link: https://patchwork.freedesktop.org/patch/msgid/20240813102505.80512-1-tursulin@igalia.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/v3d/v3d_sched.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c index b8682818bafa..ad1e6236ff6f 100644 --- a/drivers/gpu/drm/v3d/v3d_sched.c +++ b/drivers/gpu/drm/v3d/v3d_sched.c @@ -134,6 +134,8 @@ v3d_job_start_stats(struct v3d_job *job, enum v3d_queue queue) struct v3d_stats *local_stats = &file->stats[queue]; u64 now = local_clock(); + preempt_disable(); + write_seqcount_begin(&local_stats->lock); local_stats->start_ns = now; write_seqcount_end(&local_stats->lock); @@ -141,6 +143,8 @@ v3d_job_start_stats(struct v3d_job *job, enum v3d_queue queue) write_seqcount_begin(&global_stats->lock); global_stats->start_ns = now; write_seqcount_end(&global_stats->lock); + + preempt_enable(); } static void @@ -162,8 +166,10 @@ v3d_job_update_stats(struct v3d_job *job, enum v3d_queue queue) struct v3d_stats *local_stats = &file->stats[queue]; u64 now = local_clock(); + preempt_disable(); v3d_stats_update(local_stats, now); v3d_stats_update(global_stats, now); + preempt_enable(); } static struct dma_fence *v3d_bin_job_run(struct drm_sched_job *sched_job) -- 2.46.0