From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Denis Bolotin , Michal Kalderon , "David S. Miller" , Sasha Levin Subject: [PATCH 4.19 021/118] qed: Fix reading wrong value in loop condition Date: Tue, 11 Dec 2018 16:40:40 +0100 Message-Id: <20181211151645.097394258@linuxfoundation.org> In-Reply-To: <20181211151644.216668863@linuxfoundation.org> References: <20181211151644.216668863@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit ed4eac20dcffdad47709422e0cb925981b056668 ] The value of "sb_index" is written by the hardware. Reading its value and writing it to "index" must finish before checking the loop condition. Signed-off-by: Denis Bolotin Signed-off-by: Michal Kalderon Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/qlogic/qed/qed_int.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/qlogic/qed/qed_int.c b/drivers/net/ethernet/qlogic/qed/qed_int.c index 0f0aba793352..b22f464ea3fa 100644 --- a/drivers/net/ethernet/qlogic/qed/qed_int.c +++ b/drivers/net/ethernet/qlogic/qed/qed_int.c @@ -992,6 +992,8 @@ static int qed_int_attentions(struct qed_hwfn *p_hwfn) */ do { index = p_sb_attn->sb_index; + /* finish reading index before the loop condition */ + dma_rmb(); attn_bits = le32_to_cpu(p_sb_attn->atten_bits); attn_acks = le32_to_cpu(p_sb_attn->atten_ack); } while (index != p_sb_attn->sb_index); -- 2.19.1