Re: [PATCH v2 2/4] cxl/memdev: Hold memdev lock during memdev poison injection/clear

Dave Jiang
2026-03-18T15:36:34Z

On 3/18/26 4:59 AM, Li Ming wrote:
>
> 在 2026/3/17 23:00, Dave Jiang 写道:
>>
>> On 3/14/26 12:06 AM, Li Ming wrote:
>>> CXL memdev poison injection/clearing debugfs interfaces are visible
>>> before the CXL memdev endpoint initialization, If user accesses the
>>> interfaces before cxlmd->endpoint updated, it is possible to access an
>>> invalid endpoint in cxl_dpa_to_region().
>>>
>>> Hold CXL memdev lock at the beginning of the interfaces, this blocks the
>>> interfaces until CXL memdev probing completed.
>>>
>>> The following patch will check the given endpoint validity in
>>> cxl_dpa_to_region().
>>>
>>> Suggested-by: Dan Williams <dan.j.williams@intel.com>
>>> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
>>> Reviewed-by: Alison Schofield <alison.schofield@intel.com>
>>> Signed-off-by: Li Ming <ming.li@zohomail.com>
>> Hi Ming, I dropped this patch with Dan's comments [1] and updated cxl/next. Please check and make sure everything looks ok to you. Thanks!
>>
>> [1]: https://lore.kernel.org/linux-cxl/69b8b81621e16_452b100e@dwillia2-mobl4.notmuch/
>
> Hi Dave,
>
> I think there is no change needed in this patch, just need a independent patch for holding memdev lock in cxl_region_debugfs_poison_inject/clear.
>
> Or you want to review this patch again?

No. Maybe I misunderstood the comment from Dan. So we should keep this patch?

DJ