Re: [PATCH v7 3/7] cxl/region: Don't leak tolerated RAM -EFAULT from unmapped poison scan

[Alison Schofield]

On Wed, Sep 02, 2026 at 01:38:35PM +0800, Richard Cheng wrote:
> cxl_get_poison_unmapped() tolerates the -EFAULT a RAM partition returns
> for Get Poison List by skipping that partition, but left rc holding the
> error. If the tolerated RAM fault was the last poison query before the
> loop ended, the function returned a spurious -EFAULT and the poison-list
> read failed even though enumeration succeeded. Reset rc to 0 when
> tolerating the fault, matching poison_by_decoder().

Reviewed-by: Alison Schofield <alison.schofield@xxxxxxxxx>

> 
> Fixes: be5cbd0840275 ("cxl: Kill enum cxl_decoder_mode")
> Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> Signed-off-by: Richard Cheng <icheng@xxxxxxxxxx>
> ---
>  drivers/cxl/core/region.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index b03f30c04d35..ddf12075b95c 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -2930,8 +2930,10 @@ static int cxl_get_poison_unmapped(struct cxl_memdev *cxlmd,
>  		if (!length)
>  			continue;
>  		rc = cxl_mem_get_poison(cxlmd, offset, length, NULL);
> -		if (rc == -EFAULT && cxlds->part[i].mode == CXL_PARTMODE_RAM)
> +		if (rc == -EFAULT && cxlds->part[i].mode == CXL_PARTMODE_RAM) {
> +			rc = 0;
>  			continue;
> +		}
>  		if (rc)
>  			break;
>  	}
> -- 
> 2.53.0
>