diff mbox series

[2/2] bus: mhi: host: Take irqsave lock after TRE is generated

Message ID 1694426069-74140-3-git-send-email-quic_qianyu@quicinc.com (mailing list archive)
State Superseded
Headers show
Series Add lock to avoid race when ringing channel DB | expand

Commit Message

Qiang Yu Sept. 11, 2023, 9:54 a.m. UTC 
From: Hemant Kumar <quic_hemantk@quicinc.com>

Take irqsave lock after TRE is generated to avoid deadlock due to core
getting interrupts enabled as local_bh_enable must not be called with
irqs disabled based on upstream patch.

Signed-off-by: Hemant Kumar <quic_hemantk@quicinc.com>
Signed-off-by: Lazarus Motha <quic_lmotha@quicinc.com>
Signed-off-by: Qiang Yu <quic_qianyu@quicinc.com>
---
 drivers/bus/mhi/host/main.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c
index ce42205..0a0b205 100644
--- a/drivers/bus/mhi/host/main.c
+++ b/drivers/bus/mhi/host/main.c
@@ -1124,17 +1124,15 @@  static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info,
 	if (unlikely(MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)))
 		return -EIO;
 
-	read_lock_irqsave(&mhi_cntrl->pm_lock, flags);
-
 	ret = mhi_is_ring_full(mhi_cntrl, tre_ring);
-	if (unlikely(ret)) {
-		ret = -EAGAIN;
-		goto exit_unlock;
-	}
+	if (unlikely(ret))
+		return -EAGAIN;
 
 	ret = mhi_gen_tre(mhi_cntrl, mhi_chan, buf_info, mflags);
 	if (unlikely(ret))
-		goto exit_unlock;
+		return ret;
+
+	read_lock_irqsave(&mhi_cntrl->pm_lock, flags);
 
 	/* Packet is queued, take a usage ref to exit M3 if necessary
 	 * for host->device buffer, balanced put is done on buffer completion
@@ -1154,7 +1152,6 @@  static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info,
 	if (dir == DMA_FROM_DEVICE)
 		mhi_cntrl->runtime_put(mhi_cntrl);
 
-exit_unlock:
 	read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags);
 
 	return ret;