1. We need a write lock in mhi_gen_tre otherwise there is race of the WP used for ringing channel DB between mhi_queue and M0 transition. 2. We can not invoke local_bh_enable() when irqs are disabled, so move read_lock_irqsave() under the mhi_gen_tre() since we add write_lock_bh() in mhi_gen_tre(). 3. Unlock xfer_cb to prevent potential lockup v1 -> v2: Added write_unlock_bh(&mhi_chan->lock) in mhi_gen_tre() before return because of error process. v2 -> v3: 1. split protecting WP and unlocking xfer_cb into two patches 2. Add a new patch to stop processing buffer and eventof a disabled or stopped channel. v3 -> v4: 1. Modify commit message 2. Add unlock operation before return error v4 -> v5: 1. Squash "protecting WP" and "Take irqsave lock" into one patch 2. Drop patch 3/4 of patch v4 Bhaumik Bhatt (1): bus: mhi: host: Add spinlock to protect WP access when queueing TREs Qiang Yu (1): bus: mhi: host: Drop chan lock before queuing buffers drivers/bus/mhi/host/main.c | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) -- 2.7.4
