Re: [PATCH v6 13/13] cxl/ras: Make cxl_cper_handle_prot_err() static

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] bus_find_device() is passed a struct pci_dev pointer instead of a struct device pointer, causing the match function to always fail and skipping CXL CPER endpoint error tracing.
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commit 8c6686bf6f4e6de777942d8a16f6142155da2ee3
Author: Dave Jiang <dave.jiang@intel.com>

cxl/ras: Make cxl_cper_handle_prot_err() static

The extlog caller went away when extlog switched to
cxl_cper_post_prot_err(), leaving cxl_cper_prot_err_work_fn() in the same
file as the only caller. Drop the export and the declaration in
<cxl/event.h>, and make it static.

> diff --git a/drivers/cxl/core/ras.c b/drivers/cxl/core/ras.c
> index e307361bb39e4..c91db125a9714 100644
> --- a/drivers/cxl/core/ras.c
> +++ b/drivers/cxl/core/ras.c
> @@ -77,7 +77,7 @@ static int match_memdev_by_parent(struct device *dev, const void *uport)
>  	return 0;
>  }
>  
> -void cxl_cper_handle_prot_err(struct cxl_cper_prot_err_work_data *data)
> +static void cxl_cper_handle_prot_err(struct cxl_cper_prot_err_work_data *data)

[Severity: High]
This is a pre-existing issue, but I noticed a bug in how this function
searches for the memdev using bus_find_device().

Does this code always fail to match the memdev, skipping the CXL CPER
endpoint error tracing entirely?

Inside cxl_cper_handle_prot_err(), bus_find_device() is called with pdev
(a struct pci_dev pointer) as the search context:

drivers/cxl/core/ras.c:cxl_cper_handle_prot_err() {
    ...
	struct device *mem_dev __free(put_device) = bus_find_device(
		&cxl_bus_type, NULL, pdev, match_memdev_by_parent);
    ...
}

However, match_memdev_by_parent() expects uport to be a pointer to a
struct device in order for the comparison to work:

drivers/cxl/core/ras.c:match_memdev_by_parent() {
	if (is_cxl_memdev(dev) && dev->parent == uport)
		return 1;
	return 0;
}

Because struct device is embedded inside struct pci_dev at a non-zero
offset, dev->parent will never equal the pdev pointer. This guarantees
bus_find_device() will return NULL, causing hardware protocol errors on
CXL memory devices to be silently dropped instead of being traced.

Should bus_find_device() be called with &pdev->dev instead of pdev?

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260904172337.1409775-1-dave.jiang@intel.com?part=13