Re: [PATCH v2 3/6] cxl/acpi: Ensure ports ready at cxl_acpi_probe() return

[Gregory Price <gourry@gourry.net>]

On Tue, Oct 22, 2024 at 06:43:40PM -0700, Dan Williams wrote:
> In order to ensure root CXL ports are enabled upon cxl_acpi_probe()
> when the 'cxl_port' driver is built as a module, arrange for the
> module to be pre-loaded or built-in.
> 
> The "Fixes:" but no "Cc: stable" on this patch reflects that the issue
> is merely by inspection since the bug that triggered the discovery of
> this potential problem [1] is fixed by other means. However, a stable
> backport should do no harm.
> 
> Fixes: 8dd2bc0f8e02 ("cxl/mem: Add the cxl_mem driver")
> Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1]
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Tested-by: Gregory Price <gourry@gourry.net>

> ---
>  drivers/cxl/acpi.c |    7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
> index 82b78e331d8e..432b7cfd12a8 100644
> --- a/drivers/cxl/acpi.c
> +++ b/drivers/cxl/acpi.c
> @@ -924,6 +924,13 @@ static void __exit cxl_acpi_exit(void)
>  
>  /* load before dax_hmem sees 'Soft Reserved' CXL ranges */
>  subsys_initcall(cxl_acpi_init);
> +
> +/*
> + * Arrange for host-bridge ports to be active synchronous with
> + * cxl_acpi_probe() exit.
> + */
> +MODULE_SOFTDEP("pre: cxl_port");
> +
>  module_exit(cxl_acpi_exit);
>  MODULE_DESCRIPTION("CXL ACPI: Platform Support");
>  MODULE_LICENSE("GPL v2");
>