From: Sascha Hauer <s.hauer@pengutronix.de>
Date: Mon, 16 Dec 2019 10:53:24 +0000 (+0100)
Subject: dmaengine: virt-dma: Add missing locking around list operations
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=9f91e6bfa8666270565fb76d883db2ba2e441585;p=openwrt%2Fstaging%2Fblogic.git

dmaengine: virt-dma: Add missing locking around list operations

All list operations are protected by &vc->lock. As vchan_vdesc_fini()
is called unlocked add the missing locking around the list operations.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191216105328.15198-6-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
---

diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index e213137b6bc1..e9f5250fbe4d 100644
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -113,10 +113,15 @@ static inline void vchan_vdesc_fini(struct virt_dma_desc *vd)
 {
 	struct virt_dma_chan *vc = to_virt_chan(vd->tx.chan);
 
-	if (dmaengine_desc_test_reuse(&vd->tx))
+	if (dmaengine_desc_test_reuse(&vd->tx)) {
+		unsigned long flags;
+
+		spin_lock_irqsave(&vc->lock, flags);
 		list_add(&vd->node, &vc->desc_allocated);
-	else
+		spin_unlock_irqrestore(&vc->lock, flags);
+	} else {
 		vc->desc_free(vd);
+	}
 }
 
 /**