[PATCH v3 07/20] cxl: harden resource_contains checks to handle zero size resources

alejandro.lucero-palau
2024-09-07T08:19:37Z

From: Alejandro Lucero <alucerop@amd.com>

For a resource defined with size zero, resource_contains returns
always true.

Add resource size check before using it.

Signed-off-by: Alejandro Lucero <alucerop@amd.com>
---
drivers/cxl/core/hdm.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
index 3df10517a327..953a5f86a43f 100644
--- a/drivers/cxl/core/hdm.c
+++ b/drivers/cxl/core/hdm.c
@@ -327,10 +327,11 @@ static int __cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled,
cxled->dpa_res = res;
cxled->skip = skipped;

- if (resource_contains(&cxlds->pmem_res, res))
+ if ((resource_size(&cxlds->pmem_res)) && (resource_contains(&cxlds->pmem_res, res))) {
cxled->mode = CXL_DECODER_PMEM;
- else if (resource_contains(&cxlds->ram_res, res))
+ } else if ((resource_size(&cxlds->ram_res)) && (resource_contains(&cxlds->ram_res, res))) {
cxled->mode = CXL_DECODER_RAM;
+ }
else {
dev_warn(dev, "decoder%d.%d: %pr mixed mode not supported\n",
port->id, cxled->cxld.id, cxled->dpa_res);
--
2.17.1