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

[Dave Jiang]

On 6/30/26 12:46 AM, 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().
> 
> Fixes: be5cbd0840275 ("cxl: Kill enum cxl_decoder_mode")
> Signed-off-by: Richard Cheng <icheng@xxxxxxxxxx>

Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>

> ---
>  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 be246fb09c99..52ba8e9e4288 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -2933,8 +2933,10 @@ 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;
>  	}