Re: [PATCH v2 1/2] cxl/cdat: Handle cdat table build errors

From: fan
Date: Tue Dec 19 2023 - 12:44:28 EST


On Wed, Nov 29, 2023 at 05:33:03PM -0800, Ira Weiny wrote:
> The callback for building CDAT tables may return negative error codes.
> This was previously unhandled and will result in potentially huge
> allocations later on in ct3_build_cdat()
>
> Detect the negative error code and defer cdat building.
>
> Fixes: f5ee7413d592 ("hw/mem/cxl-type3: Add CXL CDAT Data Object Exchange")
> Cc: Huai-Cheng Kuo <hchkuo@xxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
> hw/cxl/cxl-cdat.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/cxl/cxl-cdat.c b/hw/cxl/cxl-cdat.c
> index 639a2db3e17b..24829cf2428d 100644
> --- a/hw/cxl/cxl-cdat.c
> +++ b/hw/cxl/cxl-cdat.c
> @@ -63,7 +63,7 @@ static void ct3_build_cdat(CDATObject *cdat, Error **errp)
> cdat->built_buf_len = cdat->build_cdat_table(&cdat->built_buf,
> cdat->private);
>
> - if (!cdat->built_buf_len) {
> + if (cdat->built_buf_len <= 0) {
> /* Build later as not all data available yet */
> cdat->to_update = true;
> return;
>

The fix looks good to me. Just curious how to really build cdat table
again when an error occurs, for example, the memory allocation fails.

Fan
> --
> 2.42.0
>