clear-pkgs-linux-iot-lts2018/1097-media-intel-ipu4-ICI-VIRT-add-locking-to-BE-request-.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Ong Hock Yu <ong.hock.yu@intel.com>
Date: Tue, 28 May 2019 23:48:53 +0000
Subject: [PATCH] media: intel-ipu4: [ICI/VIRT] add locking to BE request queue
 access

Under race condition, the request queue get messed up between
put and get call to the queue. The fix is to add spinlock to
these call.

Change-Id: I842b0a26b0864128b3b881411071595d41d758f4
Tracked-On: PKT-2287
Tracked-On: HSDES-1507210582
Signed-off-by: Ong Hock Yu <ong.hock.yu@intel.com>
---
 .../virtio/intel-ipu4-virtio-be-request-queue.c  | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/media/pci/intel/virtio/intel-ipu4-virtio-be-request-queue.c b/drivers/media/pci/intel/virtio/intel-ipu4-virtio-be-request-queue.c
index cee9b55518c1..53e059c62a7c 100644
--- a/drivers/media/pci/intel/virtio/intel-ipu4-virtio-be-request-queue.c
+++ b/drivers/media/pci/intel/virtio/intel-ipu4-virtio-be-request-queue.c
@@ -47,11 +47,23 @@ void ipu4_virtio_be_req_queue_free(void)
 
 struct ipu4_virtio_req_info *ipu4_virtio_be_req_queue_get(void)
 {
-	return ipu4_virtio_ring_pop(&ipu4_virtio_be_req_queue);
+	struct ipu4_virtio_req_info *req;
+	unsigned long flags = 0;
+
+	spin_lock_irqsave(&ipu4_virtio_be_req_queue.lock, flags);
+	req = ipu4_virtio_ring_pop(&ipu4_virtio_be_req_queue);
+	spin_unlock_irqrestore(&ipu4_virtio_be_req_queue.lock, flags);
+	return req;
 }
 
 int ipu4_virtio_be_req_queue_put(
 			struct ipu4_virtio_req_info *req)
 {
-	return ipu4_virtio_ring_push(&ipu4_virtio_be_req_queue, req);
+	unsigned long flags = 0;
+	int status;
+
+	spin_lock_irqsave(&ipu4_virtio_be_req_queue.lock, flags);
+	status = ipu4_virtio_ring_push(&ipu4_virtio_be_req_queue, req);
+	spin_unlock_irqrestore(&ipu4_virtio_be_req_queue.lock, flags);
+	return status;
 }
-- 
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