This is a note to let you know that I've just added the patch titled
dmaengine: ti: k3-udma: Set bchan to NULL if a channel request fail
to the 5.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dmaengine-ti-k3-udma-set-bchan-to-null-if-a-channel-request-fail.patch
and it can be found in the queue-5.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 5c6c6d60e4b489308ae4da8424c869f7cc53cd12 Mon Sep 17 00:00:00 2001
From: Kishon Vijay Abraham I <kishon@xxxxxx>
Date: Sun, 31 Oct 2021 08:54:10 +0530
Subject: dmaengine: ti: k3-udma: Set bchan to NULL if a channel request fail
From: Kishon Vijay Abraham I <kishon@xxxxxx>
commit 5c6c6d60e4b489308ae4da8424c869f7cc53cd12 upstream.
bcdma_get_*() checks if bchan is already allocated by checking if it
has a NON NULL value. For the error cases, bchan will have error value
and bcdma_get_*() considers this as already allocated (PASS) since the
error values are NON NULL. This results in NULL pointer dereference
error while de-referencing bchan.
Reset the value of bchan to NULL if a channel request fails.
CC: stable@xxxxxxxxxxxxxxx
Acked-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxx>
Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
Link: https://lore.kernel.org/r/20211031032411.27235-2-kishon@xxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/dma/ti/k3-udma.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -1348,6 +1348,7 @@ static int bcdma_get_bchan(struct udma_c
{
struct udma_dev *ud = uc->ud;
enum udma_tp_level tpl;
+ int ret;
if (uc->bchan) {
dev_dbg(ud->dev, "chan%d: already have bchan%d allocated\n",
@@ -1365,8 +1366,11 @@ static int bcdma_get_bchan(struct udma_c
tpl = ud->bchan_tpl.levels - 1;
uc->bchan = __udma_reserve_bchan(ud, tpl, -1);
- if (IS_ERR(uc->bchan))
- return PTR_ERR(uc->bchan);
+ if (IS_ERR(uc->bchan)) {
+ ret = PTR_ERR(uc->bchan);
+ uc->bchan = NULL;
+ return ret;
+ }
uc->tchan = uc->bchan;
Patches currently in stable-queue which might be from kishon@xxxxxx are
queue-5.14/dmaengine-ti-k3-udma-set-bchan-to-null-if-a-channel-request-fail.patch
queue-5.14/arm64-dts-ti-k3-j721e-main-fix-max-virtual-functions.patch
queue-5.14/dmaengine-ti-k3-udma-set-r-tchan-or-rflow-to-null-if-request-fail.patch
queue-5.14/arm64-dts-ti-j7200-main-fix-bus-range-upto-256-bus-n.patch
queue-5.14/arm64-dts-ti-j7200-main-fix-vendor-id-device-id-prop.patch
queue-5.14/arm64-dts-ti-k3-j721e-main-fix-bus-range-upto-256-bu.patch
