From: Nilay Shroff nilay@linux.ibm.com
[ Upstream commit 863fe60ed27f2c85172654a63c5b827e72c8b2e6 ]
On system where native nvme multipath is configured and iopolicy is set to numa but the nvme controller numa node id is undefined or -1 (NUMA_NO_NODE) then avoid calculating node distance for finding optimal io path. In such case we may access numa distance table with invalid index and that may potentially refer to incorrect memory. So this patch ensures that if the nvme controller numa node id is -1 then instead of calculating node distance for finding optimal io path, we set the numa node distance of such controller to default 10 (LOCAL_DISTANCE).
Link: https://lore.kernel.org/all/20240413090614.678353-1-nilay@linux.ibm.com/ Signed-off-by: Nilay Shroff nilay@linux.ibm.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Sagi Grimberg sagi@grimberg.me Reviewed-by: Chaitanya Kulkarni kch@nvidia.com Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/multipath.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index 379d6818a0635..9f59f93b70e26 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -168,7 +168,8 @@ static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head, int node) if (nvme_path_is_disabled(ns)) continue;
- if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_NUMA) + if (ns->ctrl->numa_node != NUMA_NO_NODE && + READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_NUMA) distance = node_distance(node, ns->ctrl->numa_node); else distance = LOCAL_DISTANCE;