Changes SCMI optee transport to request an OP-TEE system invocation context per SCMI channel. This prevents possible deadlock when many Linux clients invoke OP-TEE are all suspended waiting for an OP-TEE RPC request access an SCMI resource through the SCMI OP-TEE PTA service.
Signed-off-by: Etienne Carriere etienne.carriere@linaro.org --- No change since v3
Changes since v2: - Fixed syntax issues (missing ';' chars), reported by kernel test robot.
Changes since v1: - Updated to use new tee API functions tee_client_request_system_context() and tee_client_release_system_context(). --- drivers/firmware/arm_scmi/optee.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c index 2a7aeab40e54..28a006348e1c 100644 --- a/drivers/firmware/arm_scmi/optee.c +++ b/drivers/firmware/arm_scmi/optee.c @@ -119,6 +119,7 @@ struct scmi_optee_channel { u32 tee_session; u32 caps; u32 rx_len; + bool sys_thread; struct mutex mu; struct scmi_chan_info *cinfo; union { @@ -432,9 +433,15 @@ static int scmi_optee_chan_setup(struct scmi_chan_info *cinfo, struct device *de channel->channel_id = channel_id; mutex_init(&channel->mu);
+ ret = tee_client_request_system_context(scmi_optee_private->tee_ctx); + if (ret) + dev_warn(dev, "Couldn't provision an OP-TEE system context\n"); + else + channel->sys_thread = true; + ret = setup_shmem(dev, cinfo, channel); if (ret) - return ret; + goto err_release_sysctx;
ret = open_session(scmi_optee_private, &channel->tee_session); if (ret) @@ -458,6 +465,9 @@ static int scmi_optee_chan_setup(struct scmi_chan_info *cinfo, struct device *de err_free_shm: if (channel->tee_shm) tee_shm_free(channel->tee_shm); +err_release_sysctx: + if (channel->sys_thread) + tee_client_release_system_context(scmi_optee_private->tee_ctx);
return ret; } @@ -483,6 +493,9 @@ static int scmi_optee_chan_free(int id, void *p, void *data)
scmi_free_channel(cinfo, data, id);
+ if (channel->sys_thread) + tee_client_release_system_context(scmi_optee_private->tee_ctx); + return 0; }