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 1FA093DFC77; Sat, 28 Feb 2026 17:41:13 +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=1772300474; cv=none; b=Uy59xACCQo/RLccuNIWeXVBBcY3ejonTY0KG/iCk37ACcFsa9I2bYNIegZaHj6LMNFqoZobXBlPNGldjapGonYV/o7zbTUGV1R5gSk62+KnSrul9q+WDzuO2PiqZDfNNShjl3yqCqTnHyvFTP5qhtI6VUEWqX0fMhZgQWQfMGZI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300474; c=relaxed/simple; bh=9XEM5KECmNQtwp7tgi+FFNvVL4pDMPVGmBujC3r2VIo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rmlSPMOdDEZfC4Znj1E5fuLvoet97iX+Xn56p9JqV/TpT2L1PPQH3jxD1yV0OAZb1LpLC5rR9BlQdRzG/E6gb8Z0BFoH1PgU8EmR0VQZzD+Q3wvr0UI+QO76odj2PoGUlmXskntp7I2MU6rUR6QOi+wf24ADdXUCl2BYZci4elA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=raU7AH67; 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="raU7AH67" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0437CC2BC87; Sat, 28 Feb 2026 17:41:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772300473; bh=9XEM5KECmNQtwp7tgi+FFNvVL4pDMPVGmBujC3r2VIo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=raU7AH67VPvWjb7YfXcsc/Mk1GF5cNLJkNfbYef+z3xwgPpVxBicNu678RecclFwE UkmqAiC+31cNwcnFSsqh5Xs0Tj8/nSGDlTXEfkajOHVT6UWFou5sN+A4yy8cvP1WXl WNEYD1NOxZLFl06QADbh4oaFryYw1iC5SiparVHrxzQr3OV+hHrErWAveyetUnQATf jBiI9yVjvMiwMAHVi3sg3KxGvuMxq1k8gnxkE0zEu6XEmXviL/Tnc0axv/KF19tpPC Xbb0YB5KVSnq/CtJ+wIbFYdmtMk6PuBE4VGX9kWfqLU02JkqEGqft0SO1gUcJzwUdZ YvxLlhyQVVLJw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Chia-I Wu , Boris Brezillon , Liviu Dudau , Steven Price , Sasha Levin Subject: [PATCH 6.19 512/844] drm/panthor: fix for dma-fence safe access rules Date: Sat, 28 Feb 2026 12:27:05 -0500 Message-ID: <20260228173244.1509663-513-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228173244.1509663-1-sashal@kernel.org> References: <20260228173244.1509663-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Chia-I Wu [ Upstream commit efe24898485c5c831e629d9c6fb9350c35cb576f ] Commit 506aa8b02a8d6 ("dma-fence: Add safe access helpers and document the rules") details the dma-fence safe access rules. The most common culprit is that drm_sched_fence_get_timeline_name may race with group_free_queue. Signed-off-by: Chia-I Wu Reviewed-by: Boris Brezillon Reviewed-by: Liviu Dudau Reviewed-by: Steven Price Cc: stable@vger.kernel.org # v6.17+ Signed-off-by: Steven Price Link: https://patch.msgid.link/20251204174545.399059-1-olvaffe@gmail.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/panthor/panthor_sched.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c index bd397d773d72b..5c55ba593b244 100644 --- a/drivers/gpu/drm/panthor/panthor_sched.c +++ b/drivers/gpu/drm/panthor/panthor_sched.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "panthor_devfreq.h" #include "panthor_device.h" @@ -939,6 +940,9 @@ static void group_release_work(struct work_struct *work) release_work); u32 i; + /* dma-fences may still be accessing group->queues under rcu lock. */ + synchronize_rcu(); + for (i = 0; i < group->queue_count; i++) group_free_queue(group, group->queues[i]); -- 2.51.0