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 7844B3C0A06; Wed, 30 Sep 2026 19:19:41 +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=1790795982; cv=none; b=pa7xlmqPNOXfWeT7nbuEWvVjcimVEQHjt3g5MB7rFam095YDyaL2Hab1Q1+QYds/MP7cy3qYUZmy8RLHYTDSYtlgFAHJ2Kmp2bPR5a2feZcpTR4OaWLtY/CamcziV3vXWCEFzp0qEh8RFuTK4ncLdIwB/ViVDPash4vfZpoQwP8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790795982; c=relaxed/simple; bh=fFfHfaaqdQ4yEXTdJZwr7h8R/unM70xC/++hcrWBqYE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cgMicUiDKCsmyzWyTnO/6ZpZ965ik0D69pQMWnp6BVpNZ6SQZSR8X1VRjcV67qM8XlupAZj8iVRm+Lz3j7tXTiuiAVUKQqlF0PMO6NFJlDUwhkJt09IH3l2F1vSOZKScoTLmvS6jwPcDJvQGgMXpAKR6F21tT49YeVdJneVJZCM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zmfFpF8A; 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="zmfFpF8A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D4A8E1F000FF; Wed, 30 Sep 2026 19:19:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790795981; bh=sveWny3ic3OJbxoLV9XchRymRCXZGfRlrIJtgAZOUEo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=zmfFpF8AJhffOkvaG3qJcB5Ue20ECKm70HcaF3sQDvyxccQmIqnpYYNHZMRtmrk1f jLlw7EsvM3Ustfnh31LIMxASGDE8tOubAUOlbg/KGBma41mTZQqANC3de+0MODHauW N38i5Cpg0LwBYP0AmobyvPqjV/ssyhAp1KUW9Dr4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Donggeun Yoo , Marek Szyprowski , Sasha Levin Subject: [PATCH 6.6 0750/1193] dma-coherent: report a failed reserved memory assignment Date: Wed, 30 Sep 2026 17:23:54 +0200 Message-ID: <20260930152450.913996832@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152434.301151190@linuxfoundation.org> References: <20260930152434.301151190@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Donggeun Yoo [ Upstream commit 504981db4f69bdd28054fb98c96a3a67f7248dde ] rmem_dma_device_init() drops the return value of dma_assign_coherent_memory() and always reports success. That call fails with -EBUSY when the device already has a coherent pool, and the file allows only "*one* such region of memory" per device. of_reserved_mem_device_init_by_idx() reads the zero as success. It logs "assigned reserved memory node" for a region that was not assigned and records the pairing, so of_reserved_mem_device_release() later runs rmem_dma_device_release() for it. That clears dev->dma_mem without looking at which region it was called for, dropping the pool the device did get and leaving it on ordinary memory. dma_declare_coherent_memory() checks the same call and releases the memory on failure, and rmem_swiotlb_device_init() propagates its own errors. Return the error here as well, so a device tree that assigns two pools to one device fails the probe instead of half working. Fixes: 7bfa5ab6fa1b ("drivers: dma-coherent: add initialization from device tree") Signed-off-by: Donggeun Yoo Link: https://lore.kernel.org/r/20260905074727.108029-1-donggeunyoo.kernel@gmail.com Signed-off-by: Marek Szyprowski Signed-off-by: Sasha Levin --- kernel/dma/coherent.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c index b3a6d904c0b92..133d13428714d 100644 --- a/kernel/dma/coherent.c +++ b/kernel/dma/coherent.c @@ -350,8 +350,7 @@ static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev) min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit)) dev_warn(dev, "reserved memory is beyond device's set DMA address range\n"); - dma_assign_coherent_memory(dev, mem); - return 0; + return dma_assign_coherent_memory(dev, mem); } static void rmem_dma_device_release(struct reserved_mem *rmem, -- 2.53.0