Re: [RFC PATCH 0/13] fwctl/cxl: Add CXL feature commands support via fwctl

Alejandro Lucero Palau
2024-07-19T06:23:31Z

On 7/18/24 22:32, Dave Jiang wrote:
> This series add support for CXL feature commands using the FWCTL framework [1].
> The code is untested and I'm looking for architectural and implementation feedback.
> While CXL currently has a chardev for user ioctls to send some mailbox
> commands to a memory device, the fwctl framework provides more security policies
> that can be a potential vehicle to move CXL ioctl path to that.
>
> For this RFC, the mailbox commands "Get Supported Features", "Get Feature", and
> "Set Feature" commands are implemented. The "get" commands under the
> FWCTL_RPC_DEBUG_READ_ONLY policy, the "set" command checks the policy depending
> on the effect of the feature. All mailbox commands for CXL provides an effects
> table that describes the effects of a command when performed on the device.
> For CXL features, there is also an effects field that describes the effects
> a feature write operation has on the device per feature. The security policy
> is checked against this feature specific effects field. Looking for discussion
> on matching the CXL spec defined effects with the FWCTL security policy.
>
> The code is based off of the latest FWCTL series [1] posted by Jason on top of v6.10.
>
> [1]: https://lore.kernel.org/linux-cxl/20240624161802.1b7c962d@kernel.org/T/#t
>
> ---
>
> Dave Jiang (13):
> cxl: Move mailbox related bits to the same context
> cxl: Fix comment regarding cxl_query_cmd() return data
> cxl: Refactor user ioctl command path from mds to mailbox
> cxl: Add Get Supported Features command for kernel usage
> cxl/test: Add Get Supported Features mailbox command support
> cxl: Add Get Feature command support
> cxl: Add Set Feature command support
> fwctl/cxl: Add driver for CXL mailbox for handling CXL features commands
> fwctl/cxl: Add support for get driver information
> fwctl/cxl: Add support for fwctl RPC command to enable CXL feature commands
> fwctl/cxl: Add query commands software command for ->fw_rpc()
> cxl/test: Add Get Feature support to cxl_test
> cxl/test: Add Set Feature support to cxl_test
>
> MAINTAINERS | 8 +
> drivers/cxl/core/core.h | 9 +-
> drivers/cxl/core/mbox.c | 607 ++++++++++++++++++++++++++++++++++++++++++++++++++++++---------
> drivers/cxl/core/memdev.c | 78 +++++---
> drivers/cxl/cxlmem.h | 141 +++------------
> drivers/cxl/pci.c | 68 ++++---
> drivers/cxl/pmem.c | 10 +-
> drivers/cxl/security.c | 18 +-
> drivers/fwctl/Kconfig | 9 +
> drivers/fwctl/Makefile | 1 +
> drivers/fwctl/cxl/Makefile | 4 +
> drivers/fwctl/cxl/cxl.c | 274 ++++++++++++++++++++++++++++
> include/linux/cxl/mailbox.h | 175 ++++++++++++++++++
> include/uapi/fwctl/cxl.h | 92 ++++++++++
> include/uapi/fwctl/fwctl.h | 1 +
> include/uapi/linux/cxl_mem.h | 3 +
> tools/testing/cxl/test/mem.c | 292 +++++++++++++++++++++++++++++-
> 17 files changed, 1515 insertions(+), 275 deletions(-)
>

I can not see any documentation change in that file list.

I would say for something like what this patchset does, it is mandatory.
Isn't it?