From deb1682b6f049bf5e6c496b1b2d45395ee971f32 Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Tue, 21 Apr 2020 13:40:10 +0100 Subject: [PATCH] rpmsg: glink: smem: Ensure ordering during tx [ Upstream commit 9d32497361ff89d2fc8306407de6f04b2bfb2836 ] Ensure the ordering of the fifo write and the update of the write index, so that the index is not updated before the data has landed in the fifo. Acked-By: Chris Lew Reported-by: Arun Kumar Neelakantam Signed-off-by: Bjorn Andersson Signed-off-by: Lee Jones Signed-off-by: Greg Kroah-Hartman --- drivers/rpmsg/qcom_glink_smem.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/rpmsg/qcom_glink_smem.c b/drivers/rpmsg/qcom_glink_smem.c index 69a14041ef1fe..ed616b0bc563d 100644 --- a/drivers/rpmsg/qcom_glink_smem.c +++ b/drivers/rpmsg/qcom_glink_smem.c @@ -181,6 +181,9 @@ static void glink_smem_tx_write(struct qcom_glink_pipe *glink_pipe, if (head >= pipe->native.length) head -= pipe->native.length; + /* Ensure ordering of fifo and head update */ + wmb(); + *pipe->head = cpu_to_le32(head); } -- 2.47.3