2023-10-30 15:59:54

by Sumit Garg

Subject: [PATCH v3 0/2] tee: optee: Fixes for supplicant dependent enumeration

Currently supplicant dependent optee device enumeration only registers
devices whenever tee-supplicant is invoked for the first time. But it
forgets to remove devices when tee-supplicant daemon stops running and
closes its context gracefully. This leads to following error for fTPM
driver during reboot/shutdown:

[ 73.466791] tpm tpm0: ftpm_tee_tpm_op_send: SUBMIT_COMMAND invoke error: 0xffff3024

Fix this by separating supplicant dependent devices so that the
user-space service can detach supplicant devices before closing the
supplicant. While at it use the global system workqueue for OP-TEE bus
scanning work rather than our own custom one.

Changes in v3:

- Split patch into 2 separate ones, one for supplicant fix and other for
the workqueue.

Changes in v2:

- Use device names to separate out tee-supplicant dependent devices via
this patch.
- Since user-space service is aware about tee-supplicant lifespan, so
allow the user-space service to unbind tee-supplicant dependent
devices before killing the supplicant. Following command has to be
added to the tee-supplicant service file.

$ for dev in /sys/bus/tee/devices/*; do if [[ "$dev" == *"optee-ta-supp-"* ]]; \
then echo $(basename "$dev") > $dev/driver/unbind; fi done

Sumit Garg (2):
tee: optee: Fix supplicant based device enumeration
tee: optee: Remove redundant custom workqueue

drivers/tee/optee/core.c | 13 ++-----------
drivers/tee/optee/device.c | 13 ++++++++++---
drivers/tee/optee/optee_private.h | 2 --
3 files changed, 12 insertions(+), 16 deletions(-)

--
2.34.1

2023-10-30 15:59:56

by Sumit Garg

Subject: [PATCH v3 2/2] tee: optee: Remove redundant custom workqueue

Global system workqueue is sufficient to suffice OP-TEE bus scanning work
needs. So drop redundant usage of the custom workqueue.

Tested-by: Jan Kiszka <[email protected]>
Tested-by: Masahisa Kojima <[email protected]>
Signed-off-by: Sumit Garg <[email protected]>
---
drivers/tee/optee/core.c | 13 ++-----------
drivers/tee/optee/optee_private.h | 2 --
2 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index 2a258bd3b6b5..1eaa191b6ff6 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -15,7 +15,6 @@
#include <linux/string.h>
#include <linux/tee_drv.h>
#include <linux/types.h>
-#include <linux/workqueue.h>
#include "optee_private.h"

int optee_pool_op_alloc_helper(struct tee_shm_pool *pool, struct tee_shm *shm,
@@ -110,12 +109,7 @@ int optee_open(struct tee_context *ctx, bool cap_memref_null)

if (!optee->scan_bus_done) {
INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
- optee->scan_bus_wq = create_workqueue("optee_bus_scan");
- if (!optee->scan_bus_wq) {
- kfree(ctxdata);
- return -ECHILD;
- }
- queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
+ schedule_work(&optee->scan_bus_work);
optee->scan_bus_done = true;
}
}
@@ -158,10 +152,7 @@ void optee_release_supp(struct tee_context *ctx)
struct optee *optee = tee_get_drvdata(ctx->teedev);

optee_release_helper(ctx, optee_close_session_helper);
- if (optee->scan_bus_wq) {
- destroy_workqueue(optee->scan_bus_wq);
- optee->scan_bus_wq = NULL;
- }
+
optee_supp_release(&optee->supp);
}

diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h
index 6bb5cae09688..94c0ee381894 100644
--- a/drivers/tee/optee/optee_private.h
+++ b/drivers/tee/optee/optee_private.h
@@ -178,7 +178,6 @@ struct optee_ops {
* @pool: shared memory pool
* @rpc_param_count: If > 0 number of RPC parameters to make room for
* @scan_bus_done flag if device registation was already done.
- * @scan_bus_wq workqueue to scan optee bus and register optee drivers
* @scan_bus_work workq to scan optee bus and register optee drivers
*/
struct optee {
@@ -197,7 +196,6 @@ struct optee {
struct tee_shm_pool *pool;
unsigned int rpc_param_count;
bool scan_bus_done;
- struct workqueue_struct *scan_bus_wq;
struct work_struct scan_bus_work;
};

--
2.34.1