From: Ross Zwisler <zwis...@chromium.org> commit 0efa3334d65b7f421ba12382dfa58f6ff5bf83c4 upstream.
Currently in sst_dsp_new() if we get an error return from sst_dma_new() we just print an error message and then still complete the function successfully. This means that we are trying to run without sst->dma properly set up, which will result in NULL pointer dereference when sst->dma is later used. This was happening for me in sst_dsp_dma_get_channel(): struct sst_dma *dma = dsp->dma; ... dma->ch = dma_request_channel(mask, dma_chan_filter, dsp); This resulted in: BUG: unable to handle kernel NULL pointer dereference at 0000000000000018 IP: sst_dsp_dma_get_channel+0x4f/0x125 [snd_soc_sst_firmware] Fix this by adding proper error handling for the case where we fail to set up DMA. This change only affects Haswell and Broadwell systems. Baytrail systems explicilty opt-out of DMA via sst->pdata->resindex_dma_base being set to -1. Signed-off-by: Ross Zwisler <zwis...@google.com> Cc: sta...@vger.kernel.org Acked-by: Pierre-Louis Bossart <pierre-louis.boss...@linux.intel.com> Signed-off-by: Mark Brown <broo...@kernel.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- sound/soc/intel/common/sst-firmware.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/sound/soc/intel/common/sst-firmware.c +++ b/sound/soc/intel/common/sst-firmware.c @@ -1251,11 +1251,15 @@ struct sst_dsp *sst_dsp_new(struct devic goto irq_err; err = sst_dma_new(sst); - if (err) - dev_warn(dev, "sst_dma_new failed %d\n", err); + if (err) { + dev_err(dev, "sst_dma_new failed %d\n", err); + goto dma_err; + } return sst; +dma_err: + free_irq(sst->irq, sst); irq_err: if (sst->ops->free) sst->ops->free(sst);