Re: [PATCH 4/4] cxl: Adjust offset calculation for poison injection

[Dave Jiang <dave.jiang@intel.com>]

On 10/31/25 10:32 AM, Dave Jiang wrote:
> The HPA to DPA translation for poison injection assumes that the
> base address starts from where the CXL region begins. When the
> extended linear cache is active, the offset can be within the DRAM
> region. Adjust the offset so that it correctly reflects the offset
> within the CXL region.
> 
> Signed-off-by: Dave Jiang <dave.jiang@intel.com>

This specific patch is applied to cxl/fixes
b6cfddd26ec55e865b4715f73e9bbb17a15091ed

> ---
>  drivers/cxl/core/region.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 095f5dcd17a1..eaf085aa44c4 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -3731,6 +3731,7 @@ static int cxl_region_debugfs_poison_inject(void *data, u64 offset)
>  	if (validate_region_offset(cxlr, offset))
>  		return -EINVAL;
>  
> +	offset -= cxlr->params.cache_size;
>  	rc = region_offset_to_dpa_result(cxlr, offset, &result);
>  	if (rc || !result.cxlmd || result.dpa == ULLONG_MAX) {
>  		dev_dbg(&cxlr->dev,
> @@ -3763,6 +3764,7 @@ static int cxl_region_debugfs_poison_clear(void *data, u64 offset)
>  	if (validate_region_offset(cxlr, offset))
>  		return -EINVAL;
>  
> +	offset -= cxlr->params.cache_size;
>  	rc = region_offset_to_dpa_result(cxlr, offset, &result);
>  	if (rc || !result.cxlmd || result.dpa == ULLONG_MAX) {
>  		dev_dbg(&cxlr->dev,