Re: [ndctl PATCH 0/6] Add error injection support

[Alison Schofield <alison.schofield@intel.com>]

On Thu, Apr 24, 2025 at 04:23:55PM -0500, Ben Cheatham wrote:
> This series adds support for injecting CXL protocol (CXL.cache/mem)
> errors[1] into CXL RCH Downstream ports and VH root ports[2] and
> poison into CXL memory devices through the CXL debugfs. Errors are
> injected using a new 'inject-error' command, while errors are reported
> using a new cxl-list "-N"/"--injectable-errors" option.
> 
> The 'inject-error' command and "-N" option of cxl-list both require
> access to the CXL driver's debugfs. Because the debugfs doesn't have a
> required mount point, a "--debugfs" option is added to both cxl-list and
> cxl-inject-error to specify the path to the debugfs if it isn't mounted
> to the usual place (/sys/kernel/debug).
> 
> The documentation for the new cxl-inject-error command shows both usage
> and the possible device/error types, as well as how to retrieve them
> using cxl-list. The documentation for cxl-list has also been updated to
> show the usage of the new injectable errors and debugfs options.
> 
> [1]: ACPI v6.5 spec, section 18.6.4
> [2]: ACPI v6.5 spec, table 18.31

Hi Ben,

Junkyeok Im posted a set for inject & clear poison back in 2023.[1] It
went through one round of review but was a bit ahead of it's time as we
were still working out the presentation of media-errors in the trigger
poison patch set. I'll 'cc them here in case they have interest and can
help review thi set.

How come you're not interested in implementing clear-poison?

[1] https://lore.kernel.org/linux-cxl/20230517032311.19923-1-junhyeok.im@samsung.com/

--Alison



> 
> Ben Cheatham (6):
>   libcxl: Add debugfs path to CXL context
>   libcxl: Add CXL protocol errors
>   libcxl: Add poison injection functions
>   cxl/list: Add debugfs option
>   cxl/list: Add injectable-errors option
>   cxl: Add inject-error command
> 
>  Documentation/cxl/cxl-inject-error.txt | 139 +++++++++++++++
>  Documentation/cxl/cxl-list.txt         |  39 ++++-
>  Documentation/cxl/meson.build          |   1 +
>  cxl/builtin.h                          |   1 +
>  cxl/cxl.c                              |   1 +
>  cxl/filter.h                           |   3 +
>  cxl/inject-error.c                     | 211 +++++++++++++++++++++++
>  cxl/json.c                             |  30 ++++
>  cxl/lib/libcxl.c                       | 225 +++++++++++++++++++++++++
>  cxl/lib/libcxl.sym                     |  13 ++
>  cxl/lib/private.h                      |  14 ++
>  cxl/libcxl.h                           |  17 ++
>  cxl/list.c                             |   9 +
>  cxl/meson.build                        |   1 +
>  util/json.h                            |   1 +
>  15 files changed, 704 insertions(+), 1 deletion(-)
>  create mode 100644 Documentation/cxl/cxl-inject-error.txt
>  create mode 100644 cxl/inject-error.c
> 
> -- 
> 2.34.1
>