From bce1b24d66af1e19b0483816013c5345fd96eae7 Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Thu, 26 May 2022 15:51:11 +0200 Subject: [PATCH] dmaengine: at_xdma: handle errors of at_xdmac_alloc_desc() correctly commit 3770d92bd5237d686e49da7b2fb86f53ee6ed259 upstream. It seems that it is valid to have less than the requested number of descriptors. But what is not valid and leads to subsequent errors is to have zero descriptors. In that case, abort the probing. Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver") Signed-off-by: Michael Walle Link: https://lore.kernel.org/r/20220526135111.1470926-1-michael@walle.cc Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/at_xdmac.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 2af0e151b31b8..c8dd0eef0b67b 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -1804,6 +1804,11 @@ static int at_xdmac_alloc_chan_resources(struct dma_chan *chan) for (i = 0; i < init_nr_desc_per_channel; i++) { desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC); if (!desc) { + if (i == 0) { + dev_warn(chan2dev(chan), + "can't allocate any descriptors\n"); + return -EIO; + } dev_warn(chan2dev(chan), "only %d descriptors have been allocated\n", i); break;