This RFC proposes a solution to keep protecting the fpga manager against the unloading of the low-level control modules while addressing the limitations of the current implementation. Currently, the code assumes that the low-level module registers a driver for the parent device that is later used to take the module's refcount. This proposal removes this limitation by adding a module owner field to the fpga_manager struct that can be set while registering the manager. For more context, please refer to these threads: https://lore.kernel.org/linux-fpga/ZS6hhlvjUcqyv8zL@yilunxu-OptiPlex-7050 https://lore.kernel.org/linux-fpga/ZT9qENE9fE3Z0KCW@yilunxu-OptiPlex-7050 v4: - Use helper macros to set the owner module v3: - Improved locking v2: - Fixed protection against races during module removal Marco Pagani (1): fpga: add an owner and use it to take the low-level module's refcount drivers/fpga/fpga-mgr.c | 93 ++++++++++++++++++++++------------- include/linux/fpga/fpga-mgr.h | 80 +++++++++++++++++++++++++++--- 2 files changed, 134 insertions(+), 39 deletions(-) base-commit: 610a9b8f49fbcf1100716370d3b5f6f884a2835a -- 2.43.0
