Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751409AbaKYOu2 (ORCPT ); Tue, 25 Nov 2014 09:50:28 -0500 Received: from cpanel09.rubas.ch ([195.182.222.79]:59386 "EHLO cpanel09.tophost.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751270AbaKYOuX (ORCPT ); Tue, 25 Nov 2014 09:50:23 -0500 X-Greylist: delayed 2320 seconds by postgrey-1.27 at vger.kernel.org; Tue, 25 Nov 2014 09:50:22 EST From: =?UTF-8?q?J=C3=BCrg=20Billeter?= To: Laurent Pinchart Cc: Simon Horman , Magnus Damm , Vinod Koul , Phil Edworthy , Kuninori Morimoto , linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org, dmaengine@vger.kernel.org, =?UTF-8?q?J=C3=BCrg=20Billeter?= Subject: [PATCH] dmaengine: rcar-dmac: Handle hardware descriptor allocation failure Date: Tue, 25 Nov 2014 15:10:17 +0100 Message-Id: <1416924617-15939-1-git-send-email-j@bitron.ch> X-Mailer: git-send-email 2.1.3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cpanel09.tophost.ch X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - bitron.ch X-Get-Message-Sender-Via: cpanel09.tophost.ch: authenticated_id: juerg@bitron.ch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the atomic DMA coherent pool is too small, disable use of hardware descriptor lists instead of crashing the system: ERROR: 256 KiB atomic DMA coherent pool is too small! Please increase it with coherent_pool= kernel parameter! Unable to handle kernel NULL pointer dereference at virtual address 00000004 Internal error: Oops: a07 [#1] PREEMPT SMP ARM PC is at rcar_dmac_chan_reinit+0x3c/0x160 LR is at _raw_spin_lock_irqsave+0x18/0x5c [<802132c0>] (rcar_dmac_chan_reinit) from [<80214818>] (rcar_dmac_isr_error+0x84/0xa0) [<80214818>] (rcar_dmac_isr_error) from [<80060484>] (handle_irq_event_percpu+0x50/0x150) [<80060484>] (handle_irq_event_percpu) from [<800605c0>] (handle_irq_event+0x3c/0x5c) [<800605c0>] (handle_irq_event) from [<8006350c>] (handle_fasteoi_irq+0xb8/0x198) [<8006350c>] (handle_fasteoi_irq) from [<8005fdb0>] (generic_handle_irq+0x20/0x30) [<8005fdb0>] (generic_handle_irq) from [<8000fcd0>] (handle_IRQ+0x50/0xc4) [<8000fcd0>] (handle_IRQ) from [<800092cc>] (gic_handle_irq+0x28/0x5c) [<800092cc>] (gic_handle_irq) from [<80012700>] (__irq_svc+0x40/0x70) Kernel panic - not syncing: Fatal exception in interrupt Signed-off-by: Jürg Billeter --- drivers/dma/sh/rcar-dmac.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index f8f70eb..f18b1b6 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -679,8 +679,8 @@ static void rcar_dmac_realloc_hwdesc(struct rcar_dmac_chan *chan, desc->hwdescs.size = size; } -static void rcar_dmac_fill_hwdesc(struct rcar_dmac_chan *chan, - struct rcar_dmac_desc *desc) +static int rcar_dmac_fill_hwdesc(struct rcar_dmac_chan *chan, + struct rcar_dmac_desc *desc) { struct rcar_dmac_xfer_chunk *chunk; struct rcar_dmac_hw_desc *hwdesc; @@ -689,7 +689,7 @@ static void rcar_dmac_fill_hwdesc(struct rcar_dmac_chan *chan, hwdesc = desc->hwdescs.mem; if (!hwdesc) - return; + return -ENOMEM; list_for_each_entry(chunk, &desc->chunks, node) { hwdesc->sar = chunk->src_addr; @@ -697,6 +697,8 @@ static void rcar_dmac_fill_hwdesc(struct rcar_dmac_chan *chan, hwdesc->tcr = chunk->size >> desc->xfer_shift; hwdesc++; } + + return 0; } /* ----------------------------------------------------------------------------- @@ -933,8 +935,10 @@ rcar_dmac_chan_prep_sg(struct rcar_dmac_chan *chan, struct scatterlist *sgl, * additional complexity remains to be investigated. */ desc->hwdescs.use = !highmem && nchunks > 1; - if (desc->hwdescs.use) - rcar_dmac_fill_hwdesc(chan, desc); + if (desc->hwdescs.use) { + if (rcar_dmac_fill_hwdesc(chan, desc) < 0) + desc->hwdescs.use = false; + } return &desc->async_tx; } -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/