From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 4.20 01/77] drm/msm: Unblock writer if reader closes file Date: Thu, 14 Feb 2019 21:07:39 -0500 Message-ID: <20190215020855.176727-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Sender: stable-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Kristian H. Kristensen" , "Kristian H . Kristensen" , Rob Clark , Sasha Levin , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org From: "Kristian H. Kristensen" [ Upstream commit 99c66bc051e7407fe0bf0607b142ec0be1a1d1dd ] Prevents deadlock when fifo is full and reader closes file. Signed-off-by: Kristian H. Kristensen Signed-off-by: Rob Clark Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/msm_rd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/msm_rd.c b/drivers/gpu/drm/msm/msm_rd.c index 0c2c8d2c631f..25fc161ab618 100644 --- a/drivers/gpu/drm/msm/msm_rd.c +++ b/drivers/gpu/drm/msm/msm_rd.c @@ -115,7 +115,9 @@ static void rd_write(struct msm_rd_state *rd, const void *buf, int sz) char *fptr = &fifo->buf[fifo->head]; int n; - wait_event(rd->fifo_event, circ_space(&rd->fifo) > 0); + wait_event(rd->fifo_event, circ_space(&rd->fifo) > 0 || !rd->open); + if (!rd->open) + return; /* Note that smp_load_acquire() is not strictly required * as CIRC_SPACE_TO_END() does not access the tail more @@ -213,7 +215,10 @@ static int rd_open(struct inode *inode, struct file *file) static int rd_release(struct inode *inode, struct file *file) { struct msm_rd_state *rd = inode->i_private; + rd->open = false; + wake_up_all(&rd->fifo_event); + return 0; } -- 2.19.1