From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) (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 5326B382F15; Wed, 2 Sep 2026 06:22:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=204.191.154.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788330158; cv=none; b=KlOHMRhtYZl5ami4wvXzpFDba7h1/A0ZbANvf9i1vW7Pj+TBBofxv6vF2K3uoDCM0Mcbc0m5NiaP0ZfDACEU8W6Cc11tcVQu+E+b66p657eEjan3ED1AwjnNwnDGF0GcoEhbHjDZZbp23Seo8XhnFlAyA0t3yEC2UtyaoF4gIlQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788330158; c=relaxed/simple; bh=ycRgV6qO1wDEZmcsG0HnqvCRpxdtAUy7b3nM+piqew4=; h=From:To:Cc:Date:Message-ID:In-Reply-To:References:MIME-Version: Subject; b=s+Y5UzIdT7tvSEEddbwqphYtWkEf+2AvGrXbsDlnMWVW8/8Dmf/0iz2G7iB+GXDp0oUleWh2ScTzWRZq77KfFGokOmD1Hye5LQYyhn6M045W3q24ddlrqzvcyQ7720p7sEn4OC+IauOg885dCHQoiKtX32Ujbu8Fq/V4TPd/xsU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com; spf=pass smtp.mailfrom=deltatee.com; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b=WDv/q3og; arc=none smtp.client-ip=204.191.154.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=deltatee.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b="WDv/q3og" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:MIME-Version:References:In-Reply-To: Message-ID:Date:Cc:To:From:content-disposition; bh=wfVFx652V47CW2/a10uYkNzuZ9R9O+SHTNbUJClacJA=; b=WDv/q3ogQynmjgpEn79GqLH8PC W73nqJwQMHbUGly5FfvqBrasdrC969WPL842Mx/odzgl5MzVk47jImm4U1XG4HVP7d3A0LcpFbbFn jFYng2LTr566xVfKhFbE6y9kGYUEsL+nK6BZBAFy3OytoB/sgzrZ6S5/ff6OPQnWUl/brhAg0lW98 Gf8LYwLIcKud2EoI3tIxEZCMTCiDROHWEh/KFFMn+JHzQt41TlIN+kA9IGRkwMf5gJ+mnZQfcUeRo yBwrDe2bzcmu0U0udMrPoghwRWdkqJQsfuoqJDoeO8vNmHA/b4ARx7/iO/E3QYKGU1xAH3r6HFL4q SRdo0Ftw==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1x1eMg-00000000Lqi-2Aqy; Wed, 02 Sep 2026 00:22:31 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.98.2) (envelope-from ) id 1x1eMA-0000000085N-3ArI; Wed, 02 Sep 2026 00:21:58 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, dmaengine@vger.kernel.org, Vinod Koul Cc: Frank Li , Kelvin Cao , =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= , Dave Jiang , George Ge , Jaeyoung Chung , Logan Gunthorpe , Sashiko , Frank Li Date: Wed, 2 Sep 2026 00:21:44 -0600 Message-ID: <20260902062153.31048-3-logang@deltatee.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260902062153.31048-1-logang@deltatee.com> References: <20260902062153.31048-1-logang@deltatee.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, dmaengine@vger.kernel.org, linux@weissschuh.net, dave.jiang@intel.com, kelvin.cao@microchip.com, george.ge@microchip.com, jjy600901@snu.ac.kr, logang@deltatee.com, vkoul@kernel.org, sashiko-bot@kernel.org, Frank.li@nxp.com, Frank.Li@nxp.com X-SA-Exim-Mail-From: gunthorp@deltatee.com X-Spam-Level: Subject: [PATCH v6 02/10] dmaengine: switchtec-dma: fix resource leak in alloc_chan_resources X-SA-Exim-Version: 4.2.1 (built Sun, 23 Feb 2025 07:57:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) switchtec_dma_alloc_chan_resources() returns directly on any later failure, without ever freeing the descriptor rings and coherent DMA memory it just allocated. The dmaengine core does not call device_free_chan_resources() when device_alloc_chan_resources() fails, so the driver has to unwind its own partial state. The device-removed check also runs after ring_active and comp_ring_active have already been set true, so a failure there left the channel marked active despite alloc_chan_resources() reporting failure. Add an error-unwind path that disables the channel and frees the descriptor rings on every failure after allocation. ring_active and comp_ring_active are cleared under the same locks switchtec_dma_free_chan_resources() already uses, since the completion tasklet checks comp_ring_active under complete_lock before touching the completion ring, and a stale IRQ can still be in flight when this unwind path runs. Reported-by: Sashiko Link: https://lore.kernel.org/dmaengine/20260707165555.350951F000E9@smtp.kernel.org Fixes: 30eba9df76ad ("dmaengine: switchtec-dma: Implement hardware initialization and cleanup") Reviewed-by: Frank Li Signed-off-by: Logan Gunthorpe --- drivers/dma/switchtec_dma.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/dma/switchtec_dma.c b/drivers/dma/switchtec_dma.c index a10818efba4e..e55fe9ff7e2c 100644 --- a/drivers/dma/switchtec_dma.c +++ b/drivers/dma/switchtec_dma.c @@ -988,15 +988,15 @@ static int switchtec_dma_alloc_chan_resources(struct dma_chan *chan) rc = enable_channel(swdma_chan); if (rc) - return rc; + goto err_free_desc; rc = reset_channel(swdma_chan); if (rc) - return rc; + goto err_disable_channel; rc = unhalt_channel(swdma_chan); if (rc) - return rc; + goto err_disable_channel; swdma_chan->ring_active = true; swdma_chan->comp_ring_active = true; @@ -1007,7 +1007,8 @@ static int switchtec_dma_alloc_chan_resources(struct dma_chan *chan) rcu_read_lock(); if (!rcu_dereference(swdma_dev->pdev)) { rcu_read_unlock(); - return -ENODEV; + rc = -ENODEV; + goto err_ring_inactive; } perf_cfg = readl(&swdma_chan->mmio_chan_fw->perf_cfg); @@ -1029,6 +1030,20 @@ static int switchtec_dma_alloc_chan_resources(struct dma_chan *chan) FIELD_GET(PERF_MRRS_MASK, perf_cfg)); return SWITCHTEC_DMA_SQ_SIZE; + +err_ring_inactive: + spin_lock_bh(&swdma_chan->submit_lock); + swdma_chan->ring_active = false; + spin_unlock_bh(&swdma_chan->submit_lock); + + spin_lock_bh(&swdma_chan->complete_lock); + swdma_chan->comp_ring_active = false; + spin_unlock_bh(&swdma_chan->complete_lock); +err_disable_channel: + disable_channel(swdma_chan); +err_free_desc: + switchtec_dma_free_desc(swdma_chan); + return rc; } static void switchtec_dma_free_chan_resources(struct dma_chan *chan) -- 2.47.3