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

[Dan Williams <dan.j.williams@intel.com>]

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:

-- >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);