[PATCH v2 0/6] firmware: qcom: scm: Fixes for concurrency
From: Krzysztof Kozlowski
Date: Mon Dec 09 2024 - 09:28:20 EST
Changes in v2:
- Patch #2: Extend commit msg
- Patch #4: Store NULL
- Add Rb tags
- Link to v1: https://lore.kernel.org/r/20241119-qcom-scm-missing-barriers-and-all-sort-of-srap-v1-0-7056127007a7@xxxxxxxxxx
Description
===========
SCM driver looks messy in terms of handling concurrency of probe. The
driver exports interface which is guarded by global '__scm' variable
but:
1. Lacks proper read barrier (commit adding write barriers mixed up
READ_ONCE with a read barrier).
2. Lacks barriers or checks for '__scm' in multiple places.
3. Lacks probe error cleanup.
All the issues here are non-urgent, IOW, they were here for some time
(v6.10-rc1 and earlier).
Best regards,
Krzysztof
---
Krzysztof Kozlowski (6):
firmware: qcom: scm: Fix missing read barrier in qcom_scm_is_available()
firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool()
firmware: qcom: scm: Handle various probe ordering for qcom_scm_assign_mem()
firmware: qcom: scm: Cleanup global '__scm' on probe failures
firmware: qcom: scm: smc: Handle missing SCM device
firmware: qcom: scm: smc: Narrow 'mempool' variable scope
drivers/firmware/qcom/qcom_scm-smc.c | 6 +++-
drivers/firmware/qcom/qcom_scm.c | 55 +++++++++++++++++++++++++-----------
2 files changed, 44 insertions(+), 17 deletions(-)
---
base-commit: d1486dca38afd08ca279ae94eb3a397f10737824
change-id: 20241119-qcom-scm-missing-barriers-and-all-sort-of-srap-a25d59074882
Best regards,
--
Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>