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 2307D41C72 for ; Mon, 3 Nov 2025 12:44:55 +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=1762173896; cv=none; b=ZXLtFC7QWz5C2A0EMQzrvS/gc7MGnih/DUHo6hAM1HIy7DTjYErdpksV8UotORVan+wpOPLtmbjOwiY4omZLIYx4AQMeA2xRC8DyPqftl7Cmmb6bmxNY5ZZj7+9Nd5+bWT9kB8zlus/MikyQN7+5vLvXqO1vFBq3rntcv/v1y/U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762173896; c=relaxed/simple; bh=n77TQYVTX6kaVPbYK6QUg+dmPAHNZfPVi2fidSFY7/A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YLxILQiJWZoM8ZXdu/e/8XfloaZvz28fX3qppJ0odTrSXTkGEJgCQNwSZsO4olsRG7ZBnnqD0qvAX7F5m2oqGV5ADUnVLJk3kSoMLtxntYkuZyiX8KKBncFdGr9TsGITSSFJr71LPyX98l5ZeKwy6GU3xn8Jn0FFMySUPUONK64= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bXVj6R0A; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bXVj6R0A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B5C0C4CEFD; Mon, 3 Nov 2025 12:44:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762173895; bh=n77TQYVTX6kaVPbYK6QUg+dmPAHNZfPVi2fidSFY7/A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bXVj6R0At7nl27eafmUtN6l1eLkBUx5M6S5j7OgWGzq4OqKc+t8ImO20tgF1ARNUG fY/1WDSSy+oGUR/Go5Qnsmvai2uWuH+0kv/7fqiclmzt0XNYmePY5Y190o4qBsIU+3 1njhJinf4utqdYSLHq5jMvkqGhFRi+MYmGbJL7yh9qGeXQ/yS/A2ygaLBatQHlTVW1 rHa4MRU86snT/RXElbKLPgJLw3bw8kKxkHvs+QCH7OItumN76DO3H6mRIepQyYY37x Vx2PMJ7Kt18tCuAbgZSB4+AupoTOaHtm+OHSACByMib0dyJrbyw668wmJt0JA+9oBX EtFreJxsS1GHA== From: Sasha Levin To: stable@vger.kernel.org Cc: Philipp Stanner , Tvrtko Ursulin , Sasha Levin Subject: [PATCH 6.12.y 3/3] drm/sched: Fix race in drm_sched_entity_select_rq() Date: Mon, 3 Nov 2025 07:44:50 -0500 Message-ID: <20251103124450.4002293-3-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251103124450.4002293-1-sashal@kernel.org> References: <2025110342-exhume-mankind-5952@gregkh> <20251103124450.4002293-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Philipp Stanner [ Upstream commit d25e3a610bae03bffc5c14b5d944a5d0cd844678 ] In a past bug fix it was forgotten that entity access must be protected by the entity lock. That's a data race and potentially UB. Move the spin_unlock() to the appropriate position. Cc: stable@vger.kernel.org # v5.13+ Fixes: ac4eb83ab255 ("drm/sched: select new rq even if there is only one v3") Reviewed-by: Tvrtko Ursulin Signed-off-by: Philipp Stanner Link: https://patch.msgid.link/20251022063402.87318-2-phasta@kernel.org Signed-off-by: Sasha Levin --- drivers/gpu/drm/scheduler/sched_entity.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 089e8ba0435b8..f5b5729433cbb 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -557,10 +557,11 @@ void drm_sched_entity_select_rq(struct drm_sched_entity *entity) drm_sched_rq_remove_entity(entity->rq, entity); entity->rq = rq; } - spin_unlock(&entity->lock); if (entity->num_sched_list == 1) entity->sched_list = NULL; + + spin_unlock(&entity->lock); } /** -- 2.51.0