Re: [PATCH] cxl/region: Fix memregion leaks in devm_cxl_add_region()

From: Zhijian Li (Fujitsu)
Date: Tue May 07 2024 - 01:28:55 EST




On 04/05/2024 00:07, Dan Williams wrote:
> Zhijian Li (Fujitsu) wrote:
>>> I'm not following what the problem is you are trying to fix. This seems
>>> like it just moves the memregion_free() around a bit but the logic is the
>>> same.
>>
>> This patch not only memregion_free(id) out of cxl_region_alloc() but
>> also add an extra memregion_free(id) in EINVAL case which led to a
>> memory leak previously
>>
>
> I think I would prefer to just eliminate that failure case, something
> like:

It sounds good to me. I will update it in V2

Thanks
Zhijian


>
> -- >8 --
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 5c186e0a39b9..95ba32f8649c 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -2352,15 +2352,6 @@ static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd,
> struct device *dev;
> int rc;
>
> - switch (mode) {
> - case CXL_DECODER_RAM:
> - case CXL_DECODER_PMEM:
> - break;
> - default:
> - dev_err(&cxlrd->cxlsd.cxld.dev, "unsupported mode %d\n", mode);
> - return ERR_PTR(-EINVAL);
> - }
> -
> cxlr = cxl_region_alloc(cxlrd, id);
> if (IS_ERR(cxlr))
> return cxlr;
> @@ -2415,6 +2406,15 @@ static struct cxl_region *__create_region(struct cxl_root_decoder *cxlrd,
> {
> int rc;
>
> + switch (mode) {
> + case CXL_DECODER_RAM:
> + case CXL_DECODER_PMEM:
> + break;
> + default:
> + dev_err(&cxlrd->cxlsd.cxld.dev, "unsupported mode %d\n", mode);
> + return ERR_PTR(-EINVAL);
> + }
> +
> rc = memregion_alloc(GFP_KERNEL);
> if (rc < 0)
> return ERR_PTR(rc);
>