1 From 0efa3334d65b7f421ba12382dfa58f6ff5bf83c4 Mon Sep 17 00:00:00 2001
2 From: Ross Zwisler <zwisler@chromium.org>
3 Date: Mon, 29 Apr 2019 12:25:17 -0600
4 Subject: ASoC: Intel: avoid Oops if DMA setup fails
6 From: Ross Zwisler <zwisler@chromium.org>
8 commit 0efa3334d65b7f421ba12382dfa58f6ff5bf83c4 upstream.
10 Currently in sst_dsp_new() if we get an error return from sst_dma_new()
11 we just print an error message and then still complete the function
12 successfully. This means that we are trying to run without sst->dma
13 properly set up, which will result in NULL pointer dereference when
14 sst->dma is later used. This was happening for me in
15 sst_dsp_dma_get_channel():
17 struct sst_dma *dma = dsp->dma;
19 dma->ch = dma_request_channel(mask, dma_chan_filter, dsp);
23 BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
24 IP: sst_dsp_dma_get_channel+0x4f/0x125 [snd_soc_sst_firmware]
26 Fix this by adding proper error handling for the case where we fail to
29 This change only affects Haswell and Broadwell systems. Baytrail
30 systems explicilty opt-out of DMA via sst->pdata->resindex_dma_base
33 Signed-off-by: Ross Zwisler <zwisler@google.com>
34 Cc: stable@vger.kernel.org
35 Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
36 Signed-off-by: Mark Brown <broonie@kernel.org>
37 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
40 sound/soc/intel/common/sst-firmware.c | 8 ++++++--
41 1 file changed, 6 insertions(+), 2 deletions(-)
43 --- a/sound/soc/intel/common/sst-firmware.c
44 +++ b/sound/soc/intel/common/sst-firmware.c
45 @@ -1251,11 +1251,15 @@ struct sst_dsp *sst_dsp_new(struct devic
48 err = sst_dma_new(sst);
50 - dev_warn(dev, "sst_dma_new failed %d\n", err);
52 + dev_err(dev, "sst_dma_new failed %d\n", err);
59 + free_irq(sst->irq, sst);