From 86cb0defe0e275453bc39e856bb523eb425a6537 Mon Sep 17 00:00:00 2001
From: Ben Dooks <ben.dooks@sifive.com>
Date: Fri, 8 Jul 2022 18:01:52 +0100
Subject: [PATCH] dmaengine: dw-axi-dmac: do not print NULL LLI during error
Git-commit: 86cb0defe0e275453bc39e856bb523eb425a6537
Patch-mainline: v6.0-rc1
References: git-fixes

During debugging we have seen an issue where axi_chan_dump_lli()
is passed a NULL LLI pointer which ends up causing an OOPS due
to trying to get fields from it. Simply print NULL LLI and exit
to avoid this.

Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
Link: https://lore.kernel.org/r/20220708170153.269991-3-ben.dooks@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
index e9c9bcb1f5c2..abc2a919a11c 100644
--- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
+++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c
@@ -982,6 +982,11 @@ static int dw_axi_dma_chan_slave_config(struct dma_chan *dchan,
 static void axi_chan_dump_lli(struct axi_dma_chan *chan,
 			      struct axi_dma_hw_desc *desc)
 {
+	if (!desc->lli) {
+		dev_err(dchan2dev(&chan->vc.chan), "NULL LLI\n");
+		return;
+	}
+
 	dev_err(dchan2dev(&chan->vc.chan),
 		"SAR: 0x%llx DAR: 0x%llx LLP: 0x%llx BTS 0x%x CTL: 0x%x:%08x",
 		le64_to_cpu(desc->lli->sar),
-- 
2.35.3