diff options
| author | Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> | 2023-01-23 10:29:45 +0300 |
|---|---|---|
| committer | Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> | 2023-01-27 10:01:41 +0300 |
| commit | 1ddc7618294084fff8d673217a9479550990ee84 (patch) | |
| tree | a1c166517bd8d83b03148acd64d76d7d0cbf551a /include/linux/mhi_ep.h | |
| parent | 8a1c24bb908f9ecbc4be0fea014df67d43161551 (diff) | |
| download | linux-1ddc7618294084fff8d673217a9479550990ee84.tar.xz | |
bus: mhi: ep: Change state_lock to mutex
state_lock, the spinlock type is meant to protect race against concurrent
MHI state transitions. In mhi_ep_set_m0_state(), while the state_lock is
being held, the channels are resumed in mhi_ep_resume_channels() if the
previous state was M3. This causes sleeping in atomic bug, since
mhi_ep_resume_channels() use mutex internally.
Since the state_lock is supposed to be held throughout the state change,
it is not ideal to drop the lock before calling mhi_ep_resume_channels().
So to fix this issue, let's change the type of state_lock to mutex. This
would also allow holding the lock throughout all state transitions thereby
avoiding any potential race.
Cc: <stable@vger.kernel.org> # 5.19
Fixes: e4b7b5f0f30a ("bus: mhi: ep: Add support for suspending and resuming channels")
Reported-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Diffstat (limited to 'include/linux/mhi_ep.h')
| -rw-r--r-- | include/linux/mhi_ep.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/mhi_ep.h b/include/linux/mhi_ep.h index 478aece17046..f198a8ac7ee7 100644 --- a/include/linux/mhi_ep.h +++ b/include/linux/mhi_ep.h @@ -70,8 +70,8 @@ struct mhi_ep_db_info { * @cmd_ctx_cache_phys: Physical address of the host command context cache * @chdb: Array of channel doorbell interrupt info * @event_lock: Lock for protecting event rings - * @list_lock: Lock for protecting state transition and channel doorbell lists * @state_lock: Lock for protecting state transitions + * @list_lock: Lock for protecting state transition and channel doorbell lists * @st_transition_list: List of state transitions * @ch_db_list: List of queued channel doorbells * @wq: Dedicated workqueue for handling rings and state changes @@ -117,8 +117,8 @@ struct mhi_ep_cntrl { struct mhi_ep_db_info chdb[4]; struct mutex event_lock; + struct mutex state_lock; spinlock_t list_lock; - spinlock_t state_lock; struct list_head st_transition_list; struct list_head ch_db_list; |