[PATCH 3.19.y-ckt 058/130] mmc: sdhci check parameters before call dma_free_coherent

[Kamal Mostafa]

3.19.8-ckt6 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Peng Fan <van.freenix at gmail.com>

commit 7ac020366b0a436d726408841160b5dc32c19214 upstream.

We should not call dma_free_coherent if host->adma_table is NULL,
otherwise may trigger panic.

Fixes: d1e49f77d7c7 ("mmc: sdhci: convert ADMA descriptors to a...")
Signed-off-by: Peng Fan <van.freenix at gmail.com>
Acked-by: Adrian Hunter <adrian.hunter at intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/mmc/host/sdhci.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 5c8b463..afb477a 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2971,8 +2971,11 @@ int sdhci_add_host(struct sdhci_host *host)
 						      GFP_KERNEL);
 		host->align_buffer = kmalloc(host->align_buffer_sz, GFP_KERNEL);
 		if (!host->adma_table || !host->align_buffer) {
-			dma_free_coherent(mmc_dev(mmc), host->adma_table_sz,
-					  host->adma_table, host->adma_addr);
+			if (host->adma_table)
+				dma_free_coherent(mmc_dev(mmc),
+						  host->adma_table_sz,
+						  host->adma_table,
+						  host->adma_addr);
 			kfree(host->align_buffer);
 			pr_warn("%s: Unable to allocate ADMA buffers - falling back to standard DMA\n",
 				mmc_hostname(mmc));
-- 
1.9.1