From patchwork Tue Oct 25 09:02:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tudor Ambarus X-Patchwork-Id: 13018804 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 62EC7C38A2D for ; Tue, 25 Oct 2022 09:06:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=qxF+yDnKiKydxhuf/Z/mxe+asjuu28G6eNlyYPfKKjk=; b=pHLihI1jraQ4Tc 1apXenzOfYCirJQwWGuv3C4ySWTSmdn/G90DH6mqIPmaZ9ORgGZyd0KVK/9xRVthi2aovHf2YeaQh 9k/LDAp8pVucUE5YN0APpP0kUmfplHEOVSPIfk2HFDdTORGK2yDutTgZgzF8LmTjkuFiTc26CBNYk /BDx6vdoUwGyddwmedh9g2EQvAzWAOiTIT92wuIUT2oHLhJikx/dYo8+dr6WoOh/xXGJMA4dBdwdG gWZ0aUrzqBA7YUmRUQ45JTDNjvKQJBNC2vbzm1j8YS6KqfsENQ0RkfAsPZLvugby/RIvbFfAGLibU CkWuVks4KJy6HDF2cEhQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1onFs5-004Q8c-MA; Tue, 25 Oct 2022 09:05:18 +0000 Received: from esa.microchip.iphmx.com ([68.232.153.233]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1onFqH-004PCX-Ou for linux-arm-kernel@lists.infradead.org; Tue, 25 Oct 2022 09:03:28 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1666688605; x=1698224605; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=l7OewSpbHJXGmYf7pMLsslFC7RsyklewLjVzhb94scc=; b=DilI6tNfwHYVhBs6vw5VKo5veGYy+6HdRKgSEz8HIdYIro2zmmxrZXeu jJniAliOxF4QqDyZDOrdyyfeKUjJt4OtSeYKWwlC7pf5vYETlDFbqYsMW ZT/NfRqsEIQV4/5dT/kCmCpRVzno/Au0d6UxzOsUMK9vG/I9i2J4Nap9j xIjLry2LrOnXv7wubTWrZoi7OIbUMlaKjdxUUKXw7bW+y9orCJeEr70RR n+3eXRcx4HcHBkcVQ7MtPN/G/JOzGAHPkjkvSR9pjq53DQJ6DLX3YDNyx HuE8a+RGGxoABvDtQXpZ/cvVtT59E+olYfGoTJRp7IXN7gEH3FVHrbpTy A==; X-IronPort-AV: E=Sophos;i="5.95,211,1661842800"; d="scan'208";a="186273050" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa3.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 25 Oct 2022 02:03:25 -0700 Received: from chn-vm-ex03.mchp-main.com (10.10.85.151) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.12; Tue, 25 Oct 2022 02:03:24 -0700 Received: from ROB-ULT-M18064N.mchp-main.com (10.10.115.15) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server id 15.1.2507.12 via Frontend Transport; Tue, 25 Oct 2022 02:03:21 -0700 From: Tudor Ambarus To: , , Subject: [PATCH v2 04/32] dmaengine: at_hdmac: Fix premature completion of desc in issue_pending Date: Tue, 25 Oct 2022 12:02:38 +0300 Message-ID: <20221025090306.297886-5-tudor.ambarus@microchip.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221025090306.297886-1-tudor.ambarus@microchip.com> References: <20221025090306.297886-1-tudor.ambarus@microchip.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221025_020325_836465_88561DE1 X-CRM114-Status: GOOD ( 10.95 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tudor Ambarus , maciej.sosnowski@intel.com, linux-kernel@vger.kernel.org, mripard@kernel.org, linux-arm-kernel@lists.infradead.org, dmaengine@vger.kernel.org, stable@vger.kernel.org, torfl6749@gmail.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Multiple calls to atc_issue_pending() could result in a premature completion of a descriptor from the atchan->active list, as the method always completed the first active descriptor from the list. Instead, issue_pending() should just take the first transaction descriptor from the pending queue, move it to active_list and start the transfer. Fixes: dc78baa2b90b ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller") Reported-by: Peter Rosin Signed-off-by: Tudor Ambarus Cc: stable@vger.kernel.org Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/ --- drivers/dma/at_hdmac.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index e9d0c3632868..cb5522417db6 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -1527,16 +1527,26 @@ atc_tx_status(struct dma_chan *chan, } /** - * atc_issue_pending - try to finish work + * atc_issue_pending - takes the first transaction descriptor in the pending + * queue and starts the transfer. * @chan: target DMA channel */ static void atc_issue_pending(struct dma_chan *chan) { - struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct at_desc *desc; + unsigned long flags; dev_vdbg(chan2dev(chan), "issue_pending\n"); - atc_advance_work(atchan); + spin_lock_irqsave(&atchan->lock, flags); + if (atc_chan_is_enabled(atchan) || list_empty(&atchan->queue)) + return spin_unlock_irqrestore(&atchan->lock, flags); + + desc = atc_first_queued(atchan); + list_move_tail(&desc->desc_node, &atchan->active_list); + atc_dostart(atchan, desc); + spin_unlock_irqrestore(&atchan->lock, flags); } /**