4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 99c66bc051e7407fe0bf0607b142ec0be1a1d1dd ]
Prevents deadlock when fifo is full and reader closes file.
Signed-off-by: Kristian H. Kristensen hoegsberg@chromium.org Signed-off-by: Rob Clark robdclark@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 0c2c8d2c631f3..25fc161ab6181 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; }